Planet MathML

The Planet MathML aggregates posts from various blogs that concern MathML. Although it is hosted by W3C, the content of the individual entries represent only the opinion of their respective authors and does not reflect the position of W3C.

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TPAC 2018 - Registration fees and hotel bookings

Source: public-mathonwebpages@w3.org Mail Archives • Alexandra Lacourba (alex@w3.org) • September 19, 2018 • Permalink

Dear Advisory Committee Representative,
Chairs, Working Groups and Community Groups who signed up to meet (bcc’ed),

A couple of reminders:

- The standard rate of EUR 135 (EUR 160 with VAT) will expire on 30 
September.
The late/onsite rate will start on 1 October and will be EUR 170 (EUR 
205 with VAT).

See registration details:
https://www.w3.org/2018/10/TPAC/Overview.html#registration

- The last special rates negotiated with hotels are about to expire:
You have until 20 September for the Crowne Plaza Lyon Cité 
Internationale and
until 21 September for the Ibis and Mercure hotels to book your room.

After these dates, the booking will be subject to availability.
Further information at: 
https://www.w3.org/2018/10/TPAC/Hotels-Transportation.html#accommodations

Thank you,

Alexandra.

-- 
Alexandra Lacourba - Administration             mailto:alex@w3.org
World Wide Web Consortium                       http://www.w3.org
W3C/ERCIM - 2004 route des Lucioles - Sophia Antipolis 06410 Biot - FR
Voice: +33.4.92.38.50.76                                        Fax: +33.4.92.38.78.22

Re: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Neil Soiffer (soiffer@alum.mit.edu) • September 10, 2018 • Permalink

I'm sure there is a clever logical formula involving N, J, V, &, |, =>, >
that ends with  ... => & > |. I'm also sure it would be entirely unparsable
by any system :-)

    Neil


On Mon, Sep 10, 2018 at 2:36 PM, Volker Sorge <volker.sorge@gmail.com>
wrote:

> I agree, it is probably just a typo. In particular since ATP systems like
> prover9 use & before |.
> I pinged Geoff to clarify.
>
> As for the classics (available here https://www.scribd.com/
> document/2519503/Frege-Gottlob-Begriffsschrift): I would still interpret
> §7 pages 11-13 as not defining a precedence order on "and" and "or". They
> are both derived as equivalent concepts via negation and material
> implication.
>
> But in all fairness. Neil, John, you are probably both right and "and"
> before "or" is the accepted precedence order.
> Don't listen to a nitpicker like me. Sorry, for causing all the confusion.
>
> Best,
> Volker
>
> PS: But for whoever is interested, there is a really good critique of
> Frege's system by Pavel Tichý.
>
>
>
>
>
>
>
> On Mon, 10 Sep 2018 at 22:03, Pedersen, John <jpederse@wiley.com> wrote:
>
>> Frege is certainly quite classical!  I wonder if the Sutcliffe page may
>> just just be a typo: in the second bullet just above where it talks about
>> the precedence order, it has P & Q listed before P | Q.  But you may have
>> at least one supporter in https://en.wikipedia.org/wiki/
>> Logical_connective#Order_of_precedence. It says near the end of that
>> section that some have changed precedence order, but it’s for disjunction
>> vs. implication and equivalence (which is also interesting -
>> https://books.google.com/books?id=DDv8Ie_jBUQC&pg=
>> PA263#v=onepage&q&f=false). But the penultimate sentence does say,
>> although without any supporting citation, that  conjunction/disjunction
>> precedence may be unspecified. In any case, I would certainly agree that
>> it’s best for students (and everyone) to use parentheses for
>> conjuction/disjunction to make everyone’s understanding clear.
>>
>>
>>
>>
>>
>> *From:* Volker Sorge <volker.sorge@gmail.com>
>> *Sent:* Monday, September 10, 2018 4:33 PM
>> *To:* Pedersen, John <jpederse@wiley.com>
>> *Cc:* Neil Soiffer <soiffer@alum.mit.edu>; Peter Krautzberger <
>> peter@krautzource.com>; mathonweb <public-mathonwebpages@w3.org>
>> *Subject:* Re: [mathonweb] reminder: meetings this week
>>
>>
>>
>> I might be wrong then. All I can find quickly is Geoff Sutcliffe's page
>> (some way down):
>>
>> http://www.cs.miami.edu/home/geoff/Courses/COMP6210-10M/
>> Content/Propositional.shtml
>>
>> I also seem to recall from reading Frege that he does not define an
>> order. But it's been a while since I've read Begriffsschrift.
>>
>> Anyway, I generally teach my students to better check the definitions
>> before assuming an order on those two connectives with any author. (And I
>> require them to use parentheses.)
>>
>>
>>
>> Best,
>>
>> Volker
>>
>>
>>
>> On Mon, 10 Sep 2018 at 21:20, Pedersen, John <jpederse@wiley.com> wrote:
>>
>> Although it’s been a while, I did teach undergraduate and graduate-level
>> logic and algebra for a number of years and I have the same understanding
>> as Neil that in propositional, first, and higher-level logics, conjunction
>> has priority over disjunction. There are numerous classic texts where this
>> is given as the rule. Can you point to any text or other source where the
>> order is stated to be different?
>>
>>
>>
>> *From:* Volker Sorge <volker.sorge@gmail.com>
>> *Sent:* Monday, September 10, 2018 3:51 PM
>> *To:* Neil Soiffer <soiffer@alum.mit.edu>
>> *Cc:* Peter Krautzberger <peter@krautzource.com>; mathonweb <
>> public-mathonwebpages@w3.org>
>> *Subject:* Re: [mathonweb] reminder: meetings this week
>>
>>
>>
>> I am confused; I don't understand your point. I was explicitly referring
>> to classical logic.
>>
>> Of course you can define a precedence order. Programming languages often
>> do following Boolean algebra habits, so do often authors of logic text
>> books. But even then the order between and/or can depend on the author.
>>
>>
>>
>>
>>
>>
>>
>> On Mon, 10 Sep 2018 at 19:10, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>>
>> I disagree about there not being an accepted precedence for *and* vs *or*.
>> The precedence in programming languages that I know all have *and *with
>> a higher precedence than *or*. In MathML, the default operator table
>> does so also. The other notation used for logical and/or is  ·/+ (as in a
>> ·b + c or ab+c) and these again use the convention that the "times"
>> operator has a higher precedence than "plus" for and/or.
>>
>>
>>
>> It may be that some books/articles do it the other way around, but I'd
>> like to see some examples proving me wrong. Or if they are considered equal
>> precedence, again, I'd like to see some examples where this is true (as
>> opposed to just using parens to make it clearer).
>>
>>
>>
>>     Neil
>>
>>
>>
>>
>>
>> On Mon, Sep 10, 2018 at 10:55 AM, Volker Sorge <volker.sorge@gmail.com>
>> wrote:
>>
>> There is no precedence order for logical and/or ∧/∨.
>>
>> Precedence in classical logic is: negation over conjunction/disjunction
>> over (material) implication over equivalence.
>>
>> You always need to disambiguate order of and/or.
>>
>> Volker
>>
>>
>>
>> On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>>
>> Apologies for missing the meeting today -- I don't seem to have the
>> meetings properly entered into my calendar and due to the time difference,
>> I don't see Peter's reminders until after I start work.
>>
>>
>>
>> I have a question about what someone wrote on the Wiki:
>>
>>      a∧b∨c it is not clear the order precedence. Usually ∧ has
>> precedence over ∨, but not always.
>>
>>
>>
>> Can someone clarify (on the wiki) *when* it the normal precedence
>> doesn't hold. What surprised me when I first looked into notations and
>> precedence (20 years ago -- yikes!) was that although a symbols might have
>> many different meanings, the precedence relationships it has didn't seem to
>> change. I attributed that to people trying to avoid confusion when using
>> familiar notation for new functionality. Having '∨' have a different
>> precedence relative to '∧' in some cases seems very strange to me. But
>> mathematicians do strange things at times (especially logicians ;-).
>>
>>
>>
>>     Neil
>>
>>
>>
>>
>>
>>
>> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>>
>> Virus-free. www.avg.com
>> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>>
>>
>>
>> On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <
>> peter@krautzource.com> wrote:
>>
>> Hi everyone,
>>
>>
>>
>> Just a quick reminder for the CG meetings this week.
>>
>>
>>
>> - a11y TF, Monday, Sept 10, 11am Eastern
>>
>> - css TF, Monday, Sept 10, 12pm Eastern
>>
>> - no CG meeting this week
>>
>>
>>
>> Best,
>>
>> Peter.
>>
>>
>>
>>
>>
>>

Re: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Volker Sorge (volker.sorge@gmail.com) • September 10, 2018 • Permalink

I agree, it is probably just a typo. In particular since ATP systems like
prover9 use & before |.
I pinged Geoff to clarify.

As for the classics (available here
https://www.scribd.com/document/2519503/Frege-Gottlob-Begriffsschrift): I
would still interpret §7 pages 11-13 as not defining a precedence order on
"and" and "or". They are both derived as equivalent concepts via negation
and material implication.

But in all fairness. Neil, John, you are probably both right and "and"
before "or" is the accepted precedence order.
Don't listen to a nitpicker like me. Sorry, for causing all the confusion.

Best,
Volker

PS: But for whoever is interested, there is a really good critique of
Frege's system by Pavel Tichý.







On Mon, 10 Sep 2018 at 22:03, Pedersen, John <jpederse@wiley.com> wrote:

> Frege is certainly quite classical!  I wonder if the Sutcliffe page may
> just just be a typo: in the second bullet just above where it talks about
> the precedence order, it has P & Q listed before P | Q.  But you may have
> at least one supporter in
> https://en.wikipedia.org/wiki/Logical_connective#Order_of_precedence. It
> says near the end of that section that some have changed precedence order,
> but it’s for disjunction vs. implication and equivalence (which is also
> interesting -
> https://books.google.com/books?id=DDv8Ie_jBUQC&pg=PA263#v=onepage&q&f=false).
> But the penultimate sentence does say, although without any supporting
> citation, that  conjunction/disjunction precedence may be unspecified. In
> any case, I would certainly agree that it’s best for students (and
> everyone) to use parentheses for conjuction/disjunction to make everyone’s
> understanding clear.
>
>
>
>
>
> *From:* Volker Sorge <volker.sorge@gmail.com>
> *Sent:* Monday, September 10, 2018 4:33 PM
> *To:* Pedersen, John <jpederse@wiley.com>
> *Cc:* Neil Soiffer <soiffer@alum.mit.edu>; Peter Krautzberger <
> peter@krautzource.com>; mathonweb <public-mathonwebpages@w3.org>
> *Subject:* Re: [mathonweb] reminder: meetings this week
>
>
>
> I might be wrong then. All I can find quickly is Geoff Sutcliffe's page
> (some way down):
>
>
> http://www.cs.miami.edu/home/geoff/Courses/COMP6210-10M/Content/Propositional.shtml
>
> I also seem to recall from reading Frege that he does not define an order.
> But it's been a while since I've read Begriffsschrift.
>
> Anyway, I generally teach my students to better check the definitions
> before assuming an order on those two connectives with any author. (And I
> require them to use parentheses.)
>
>
>
> Best,
>
> Volker
>
>
>
> On Mon, 10 Sep 2018 at 21:20, Pedersen, John <jpederse@wiley.com> wrote:
>
> Although it’s been a while, I did teach undergraduate and graduate-level
> logic and algebra for a number of years and I have the same understanding
> as Neil that in propositional, first, and higher-level logics, conjunction
> has priority over disjunction. There are numerous classic texts where this
> is given as the rule. Can you point to any text or other source where the
> order is stated to be different?
>
>
>
> *From:* Volker Sorge <volker.sorge@gmail.com>
> *Sent:* Monday, September 10, 2018 3:51 PM
> *To:* Neil Soiffer <soiffer@alum.mit.edu>
> *Cc:* Peter Krautzberger <peter@krautzource.com>; mathonweb <
> public-mathonwebpages@w3.org>
> *Subject:* Re: [mathonweb] reminder: meetings this week
>
>
>
> I am confused; I don't understand your point. I was explicitly referring
> to classical logic.
>
> Of course you can define a precedence order. Programming languages often
> do following Boolean algebra habits, so do often authors of logic text
> books. But even then the order between and/or can depend on the author.
>
>
>
>
>
>
>
> On Mon, 10 Sep 2018 at 19:10, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>
> I disagree about there not being an accepted precedence for *and* vs *or*.
> The precedence in programming languages that I know all have *and *with a
> higher precedence than *or*. In MathML, the default operator table does
> so also. The other notation used for logical and/or is  ·/+ (as in a ·b + c
> or ab+c) and these again use the convention that the "times" operator has a
> higher precedence than "plus" for and/or.
>
>
>
> It may be that some books/articles do it the other way around, but I'd
> like to see some examples proving me wrong. Or if they are considered equal
> precedence, again, I'd like to see some examples where this is true (as
> opposed to just using parens to make it clearer).
>
>
>
>     Neil
>
>
>
>
>
> On Mon, Sep 10, 2018 at 10:55 AM, Volker Sorge <volker.sorge@gmail.com>
> wrote:
>
> There is no precedence order for logical and/or ∧/∨.
>
> Precedence in classical logic is: negation over conjunction/disjunction
> over (material) implication over equivalence.
>
> You always need to disambiguate order of and/or.
>
> Volker
>
>
>
> On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>
> Apologies for missing the meeting today -- I don't seem to have the
> meetings properly entered into my calendar and due to the time difference,
> I don't see Peter's reminders until after I start work.
>
>
>
> I have a question about what someone wrote on the Wiki:
>
>      a∧b∨c it is not clear the order precedence. Usually ∧ has precedence
> over ∨, but not always.
>
>
>
> Can someone clarify (on the wiki) *when* it the normal precedence doesn't
> hold. What surprised me when I first looked into notations and precedence
> (20 years ago -- yikes!) was that although a symbols might have many
> different meanings, the precedence relationships it has didn't seem to
> change. I attributed that to people trying to avoid confusion when using
> familiar notation for new functionality. Having '∨' have a different
> precedence relative to '∧' in some cases seems very strange to me. But
> mathematicians do strange things at times (especially logicians ;-).
>
>
>
>     Neil
>
>
>
>
>
>
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>
> Virus-free. www.avg.com
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>
>
>
> On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <
> peter@krautzource.com> wrote:
>
> Hi everyone,
>
>
>
> Just a quick reminder for the CG meetings this week.
>
>
>
> - a11y TF, Monday, Sept 10, 11am Eastern
>
> - css TF, Monday, Sept 10, 12pm Eastern
>
> - no CG meeting this week
>
>
>
> Best,
>
> Peter.
>
>
>
>
>
>

RE: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Pedersen, John (jpederse@wiley.com) • September 10, 2018 • Permalink

Frege is certainly quite classical!  I wonder if the Sutcliffe page may just just be a typo: in the second bullet just above where it talks about the precedence order, it has P & Q listed before P | Q.  But you may have at least one supporter in https://en.wikipedia.org/wiki/Logical_connective#Order_of_precedence. It says near the end of that section that some have changed precedence order, but it’s for disjunction vs. implication and equivalence (which is also interesting - https://books.google.com/books?id=DDv8Ie_jBUQC&pg=PA263#v=onepage&q&f=false). But the penultimate sentence does say, although without any supporting citation, that  conjunction/disjunction precedence may be unspecified. In any case, I would certainly agree that it’s best for students (and everyone) to use parentheses for conjuction/disjunction to make everyone’s understanding clear.


From: Volker Sorge <volker.sorge@gmail.com>
Sent: Monday, September 10, 2018 4:33 PM
To: Pedersen, John <jpederse@wiley.com>
Cc: Neil Soiffer <soiffer@alum.mit.edu>; Peter Krautzberger <peter@krautzource.com>; mathonweb <public-mathonwebpages@w3.org>
Subject: Re: [mathonweb] reminder: meetings this week

I might be wrong then. All I can find quickly is Geoff Sutcliffe's page (some way down):
http://www.cs.miami.edu/home/geoff/Courses/COMP6210-10M/Content/Propositional.shtml

I also seem to recall from reading Frege that he does not define an order. But it's been a while since I've read Begriffsschrift.
Anyway, I generally teach my students to better check the definitions before assuming an order on those two connectives with any author. (And I require them to use parentheses.)

Best,
Volker

On Mon, 10 Sep 2018 at 21:20, Pedersen, John <jpederse@wiley.com<mailto:jpederse@wiley.com>> wrote:
Although it’s been a while, I did teach undergraduate and graduate-level logic and algebra for a number of years and I have the same understanding as Neil that in propositional, first, and higher-level logics, conjunction has priority over disjunction. There are numerous classic texts where this is given as the rule. Can you point to any text or other source where the order is stated to be different?

From: Volker Sorge <volker.sorge@gmail.com<mailto:volker.sorge@gmail.com>>
Sent: Monday, September 10, 2018 3:51 PM
To: Neil Soiffer <soiffer@alum.mit.edu<mailto:soiffer@alum.mit.edu>>
Cc: Peter Krautzberger <peter@krautzource.com<mailto:peter@krautzource.com>>; mathonweb <public-mathonwebpages@w3.org<mailto:public-mathonwebpages@w3.org>>
Subject: Re: [mathonweb] reminder: meetings this week

I am confused; I don't understand your point. I was explicitly referring to classical logic.
Of course you can define a precedence order. Programming languages often do following Boolean algebra habits, so do often authors of logic text books. But even then the order between and/or can depend on the author.



On Mon, 10 Sep 2018 at 19:10, Neil Soiffer <soiffer@alum.mit.edu<mailto:soiffer@alum.mit.edu>> wrote:
I disagree about there not being an accepted precedence for and vs or. The precedence in programming languages that I know all have and with a higher precedence than or. In MathML, the default operator table does so also. The other notation used for logical and/or is  ·/+ (as in a ·b + c or ab+c) and these again use the convention that the "times" operator has a higher precedence than "plus" for and/or.

It may be that some books/articles do it the other way around, but I'd like to see some examples proving me wrong. Or if they are considered equal precedence, again, I'd like to see some examples where this is true (as opposed to just using parens to make it clearer).

    Neil


On Mon, Sep 10, 2018 at 10:55 AM, Volker Sorge <volker.sorge@gmail.com<mailto:volker.sorge@gmail.com>> wrote:
There is no precedence order for logical and/or ∧/∨.
Precedence in classical logic is: negation over conjunction/disjunction over (material) implication over equivalence.
You always need to disambiguate order of and/or.
Volker

On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu<mailto:soiffer@alum.mit.edu>> wrote:
Apologies for missing the meeting today -- I don't seem to have the meetings properly entered into my calendar and due to the time difference, I don't see Peter's reminders until after I start work.

I have a question about what someone wrote on the Wiki:
     a∧b∨c it is not clear the order precedence. Usually ∧ has precedence over ∨, but not always.

Can someone clarify (on the wiki) when it the normal precedence doesn't hold. What surprised me when I first looked into notations and precedence (20 years ago -- yikes!) was that although a symbols might have many different meanings, the precedence relationships it has didn't seem to change. I attributed that to people trying to avoid confusion when using familiar notation for new functionality. Having '∨' have a different precedence relative to '∧' in some cases seems very strange to me. But mathematicians do strange things at times (especially logicians ;-).

    Neil


[https://ipmcdn.avast.com/images/icons/icon-envelope-tick-green-avg-v1.png]<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>

Virus-free. www.avg.com<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>


On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <peter@krautzource.com<mailto:peter@krautzource.com>> wrote:
Hi everyone,

Just a quick reminder for the CG meetings this week.

- a11y TF, Monday, Sept 10, 11am Eastern
- css TF, Monday, Sept 10, 12pm Eastern
- no CG meeting this week

Best,
Peter.


Re: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Volker Sorge (volker.sorge@gmail.com) • September 10, 2018 • Permalink

I might be wrong then. All I can find quickly is Geoff Sutcliffe's page
(some way down):
http://www.cs.miami.edu/home/geoff/Courses/COMP6210-10M/Content/Propositional.shtml
I also seem to recall from reading Frege that he does not define an order.
But it's been a while since I've read Begriffsschrift.
Anyway, I generally teach my students to better check the definitions
before assuming an order on those two connectives with any author. (And I
require them to use parentheses.)

Best,
Volker

On Mon, 10 Sep 2018 at 21:20, Pedersen, John <jpederse@wiley.com> wrote:

> Although it’s been a while, I did teach undergraduate and graduate-level
> logic and algebra for a number of years and I have the same understanding
> as Neil that in propositional, first, and higher-level logics, conjunction
> has priority over disjunction. There are numerous classic texts where this
> is given as the rule. Can you point to any text or other source where the
> order is stated to be different?
>
>
>
> *From:* Volker Sorge <volker.sorge@gmail.com>
> *Sent:* Monday, September 10, 2018 3:51 PM
> *To:* Neil Soiffer <soiffer@alum.mit.edu>
> *Cc:* Peter Krautzberger <peter@krautzource.com>; mathonweb <
> public-mathonwebpages@w3.org>
> *Subject:* Re: [mathonweb] reminder: meetings this week
>
>
>
> I am confused; I don't understand your point. I was explicitly referring
> to classical logic.
>
> Of course you can define a precedence order. Programming languages often
> do following Boolean algebra habits, so do often authors of logic text
> books. But even then the order between and/or can depend on the author.
>
>
>
>
>
>
>
> On Mon, 10 Sep 2018 at 19:10, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>
> I disagree about there not being an accepted precedence for * and* vs *or*.
> The precedence in programming languages that I know all have *and *with a
> higher precedence than *or*. In MathML, the default operator table does
> so also. The other notation used for logical and/or is  ·/+ (as in a ·b + c
> or ab+c) and these again use the convention that the "times" operator has a
> higher precedence than "plus" for and/or.
>
>
>
> It may be that some books/articles do it the other way around, but I'd
> like to see some examples proving me wrong. Or if they are considered equal
> precedence, again, I'd like to see some examples where this is true (as
> opposed to just using parens to make it clearer).
>
>
>
>     Neil
>
>
>
>
>
> On Mon, Sep 10, 2018 at 10:55 AM, Volker Sorge <volker.sorge@gmail.com>
> wrote:
>
> There is no precedence order for logical and/or ∧/∨.
>
> Precedence in classical logic is: negation over conjunction/disjunction
> over (material) implication over equivalence.
>
> You always need to disambiguate order of and/or.
>
> Volker
>
>
>
> On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>
> Apologies for missing the meeting today -- I don't seem to have the
> meetings properly entered into my calendar and due to the time difference,
> I don't see Peter's reminders until after I start work.
>
>
>
> I have a question about what someone wrote on the Wiki:
>
>      a∧b∨c it is not clear the order precedence. Usually ∧ has precedence
> over ∨, but not always.
>
>
>
> Can someone clarify (on the wiki) *when* it the normal precedence doesn't
> hold. What surprised me when I first looked into notations and precedence
> (20 years ago -- yikes!) was that although a symbols might have many
> different meanings, the precedence relationships it has didn't seem to
> change. I attributed that to people trying to avoid confusion when using
> familiar notation for new functionality. Having '∨' have a different
> precedence relative to '∧' in some cases seems very strange to me. But
> mathematicians do strange things at times (especially logicians ;-).
>
>
>
>     Neil
>
>
>
>
>
>
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>
> Virus-free. www.avg.com
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>
>
>
> On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <
> peter@krautzource.com> wrote:
>
> Hi everyone,
>
>
>
> Just a quick reminder for the CG meetings this week.
>
>
>
> - a11y TF, Monday, Sept 10, 11am Eastern
>
> - css TF, Monday, Sept 10, 12pm Eastern
>
> - no CG meeting this week
>
>
>
> Best,
>
> Peter.
>
>
>
>
>
>

RE: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Pedersen, John (jpederse@wiley.com) • September 10, 2018 • Permalink

Although it’s been a while, I did teach undergraduate and graduate-level logic and algebra for a number of years and I have the same understanding as Neil that in propositional, first, and higher-level logics, conjunction has priority over disjunction. There are numerous classic texts where this is given as the rule. Can you point to any text or other source where the order is stated to be different?

From: Volker Sorge <volker.sorge@gmail.com>
Sent: Monday, September 10, 2018 3:51 PM
To: Neil Soiffer <soiffer@alum.mit.edu>
Cc: Peter Krautzberger <peter@krautzource.com>; mathonweb <public-mathonwebpages@w3.org>
Subject: Re: [mathonweb] reminder: meetings this week

I am confused; I don't understand your point. I was explicitly referring to classical logic.
Of course you can define a precedence order. Programming languages often do following Boolean algebra habits, so do often authors of logic text books. But even then the order between and/or can depend on the author.



On Mon, 10 Sep 2018 at 19:10, Neil Soiffer <soiffer@alum.mit.edu<mailto:soiffer@alum.mit.edu>> wrote:
I disagree about there not being an accepted precedence for and vs or. The precedence in programming languages that I know all have and with a higher precedence than or. In MathML, the default operator table does so also. The other notation used for logical and/or is  ·/+ (as in a ·b + c or ab+c) and these again use the convention that the "times" operator has a higher precedence than "plus" for and/or.

It may be that some books/articles do it the other way around, but I'd like to see some examples proving me wrong. Or if they are considered equal precedence, again, I'd like to see some examples where this is true (as opposed to just using parens to make it clearer).

    Neil


On Mon, Sep 10, 2018 at 10:55 AM, Volker Sorge <volker.sorge@gmail.com<mailto:volker.sorge@gmail.com>> wrote:
There is no precedence order for logical and/or ∧/∨.
Precedence in classical logic is: negation over conjunction/disjunction over (material) implication over equivalence.
You always need to disambiguate order of and/or.
Volker

On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu<mailto:soiffer@alum.mit.edu>> wrote:
Apologies for missing the meeting today -- I don't seem to have the meetings properly entered into my calendar and due to the time difference, I don't see Peter's reminders until after I start work.

I have a question about what someone wrote on the Wiki:
     a∧b∨c it is not clear the order precedence. Usually ∧ has precedence over ∨, but not always.

Can someone clarify (on the wiki) when it the normal precedence doesn't hold. What surprised me when I first looked into notations and precedence (20 years ago -- yikes!) was that although a symbols might have many different meanings, the precedence relationships it has didn't seem to change. I attributed that to people trying to avoid confusion when using familiar notation for new functionality. Having '∨' have a different precedence relative to '∧' in some cases seems very strange to me. But mathematicians do strange things at times (especially logicians ;-).

    Neil


[https://ipmcdn.avast.com/images/icons/icon-envelope-tick-green-avg-v1.png]<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>

Virus-free. www.avg.com<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>


On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <peter@krautzource.com<mailto:peter@krautzource.com>> wrote:
Hi everyone,

Just a quick reminder for the CG meetings this week.

- a11y TF, Monday, Sept 10, 11am Eastern
- css TF, Monday, Sept 10, 12pm Eastern
- no CG meeting this week

Best,
Peter.


Re: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Volker Sorge (volker.sorge@gmail.com) • September 10, 2018 • Permalink

I am confused; I don't understand your point. I was explicitly referring to
classical logic.
Of course you can define a precedence order. Programming languages often do
following Boolean algebra habits, so do often authors of logic text books.
But even then the order between and/or can depend on the author.



On Mon, 10 Sep 2018 at 19:10, Neil Soiffer <soiffer@alum.mit.edu> wrote:

> I disagree about there not being an accepted precedence for *and* vs *or*.
> The precedence in programming languages that I know all have *and *with a
> higher precedence than *or*. In MathML, the default operator table does
> so also. The other notation used for logical and/or is  ·/+ (as in a ·b + c
> or ab+c) and these again use the convention that the "times" operator has a
> higher precedence than "plus" for and/or.
>
> It may be that some books/articles do it the other way around, but I'd
> like to see some examples proving me wrong. Or if they are considered equal
> precedence, again, I'd like to see some examples where this is true (as
> opposed to just using parens to make it clearer).
>
>     Neil
>
>
> On Mon, Sep 10, 2018 at 10:55 AM, Volker Sorge <volker.sorge@gmail.com>
> wrote:
>
>> There is no precedence order for logical and/or ∧/∨.
>> Precedence in classical logic is: negation over conjunction/disjunction
>> over (material) implication over equivalence.
>> You always need to disambiguate order of and/or.
>> Volker
>>
>> On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>>
>>> Apologies for missing the meeting today -- I don't seem to have the
>>> meetings properly entered into my calendar and due to the time difference,
>>> I don't see Peter's reminders until after I start work.
>>>
>>> I have a question about what someone wrote on the Wiki:
>>>
>>>>      a∧b∨c it is not clear the order precedence. Usually ∧ has
>>>> precedence over ∨, but not always.
>>>>
>>>
>>> Can someone clarify (on the wiki) *when* it the normal precedence
>>> doesn't hold. What surprised me when I first looked into notations and
>>> precedence (20 years ago -- yikes!) was that although a symbols might have
>>> many different meanings, the precedence relationships it has didn't seem to
>>> change. I attributed that to people trying to avoid confusion when using
>>> familiar notation for new functionality. Having '∨' have a different
>>> precedence relative to '∧' in some cases seems very strange to me. But
>>> mathematicians do strange things at times (especially logicians ;-).
>>>
>>>     Neil
>>>
>>>
>>>
>>> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free.
>>> www.avg.com
>>> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>>> <#m_1929109758283245939_m_-8668002184244581737_m_5378311284654993367_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>>>
>>> On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <
>>> peter@krautzource.com> wrote:
>>>
>>>> Hi everyone,
>>>>
>>>> Just a quick reminder for the CG meetings this week.
>>>>
>>>> - a11y TF, Monday, Sept 10, 11am Eastern
>>>> - css TF, Monday, Sept 10, 12pm Eastern
>>>> - no CG meeting this week
>>>>
>>>> Best,
>>>> Peter.
>>>>
>>>
>>>
>

Re: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Neil Soiffer (soiffer@alum.mit.edu) • September 10, 2018 • Permalink

I disagree about there not being an accepted precedence for *and* vs *or*.
The precedence in programming languages that I know all have *and *with a
higher precedence than *or*. In MathML, the default operator table does so
also. The other notation used for logical and/or is  ·/+ (as in a ·b + c or
ab+c) and these again use the convention that the "times" operator has a
higher precedence than "plus" for and/or.

It may be that some books/articles do it the other way around, but I'd like
to see some examples proving me wrong. Or if they are considered equal
precedence, again, I'd like to see some examples where this is true (as
opposed to just using parens to make it clearer).

    Neil


On Mon, Sep 10, 2018 at 10:55 AM, Volker Sorge <volker.sorge@gmail.com>
wrote:

> There is no precedence order for logical and/or ∧/∨.
> Precedence in classical logic is: negation over conjunction/disjunction
> over (material) implication over equivalence.
> You always need to disambiguate order of and/or.
> Volker
>
> On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>
>> Apologies for missing the meeting today -- I don't seem to have the
>> meetings properly entered into my calendar and due to the time difference,
>> I don't see Peter's reminders until after I start work.
>>
>> I have a question about what someone wrote on the Wiki:
>>
>>>      a∧b∨c it is not clear the order precedence. Usually ∧ has
>>> precedence over ∨, but not always.
>>>
>>
>> Can someone clarify (on the wiki) *when* it the normal precedence
>> doesn't hold. What surprised me when I first looked into notations and
>> precedence (20 years ago -- yikes!) was that although a symbols might have
>> many different meanings, the precedence relationships it has didn't seem to
>> change. I attributed that to people trying to avoid confusion when using
>> familiar notation for new functionality. Having '∨' have a different
>> precedence relative to '∧' in some cases seems very strange to me. But
>> mathematicians do strange things at times (especially logicians ;-).
>>
>>     Neil
>>
>>
>>
>> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free.
>> www.avg.com
>> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>> <#m_-8668002184244581737_m_5378311284654993367_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>>
>> On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <
>> peter@krautzource.com> wrote:
>>
>>> Hi everyone,
>>>
>>> Just a quick reminder for the CG meetings this week.
>>>
>>> - a11y TF, Monday, Sept 10, 11am Eastern
>>> - css TF, Monday, Sept 10, 12pm Eastern
>>> - no CG meeting this week
>>>
>>> Best,
>>> Peter.
>>>
>>
>>

Re: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Volker Sorge (volker.sorge@gmail.com) • September 10, 2018 • Permalink

There is no precedence order for logical and/or ∧/∨.
Precedence in classical logic is: negation over conjunction/disjunction
over (material) implication over equivalence.
You always need to disambiguate order of and/or.
Volker

On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu> wrote:

> Apologies for missing the meeting today -- I don't seem to have the
> meetings properly entered into my calendar and due to the time difference,
> I don't see Peter's reminders until after I start work.
>
> I have a question about what someone wrote on the Wiki:
>
>>      a∧b∨c it is not clear the order precedence. Usually ∧ has precedence
>> over ∨, but not always.
>>
>
> Can someone clarify (on the wiki) *when* it the normal precedence doesn't
> hold. What surprised me when I first looked into notations and precedence
> (20 years ago -- yikes!) was that although a symbols might have many
> different meanings, the precedence relationships it has didn't seem to
> change. I attributed that to people trying to avoid confusion when using
> familiar notation for new functionality. Having '∨' have a different
> precedence relative to '∧' in some cases seems very strange to me. But
> mathematicians do strange things at times (especially logicians ;-).
>
>     Neil
>
>
>
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free.
> www.avg.com
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
> <#m_5378311284654993367_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>
> On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <
> peter@krautzource.com> wrote:
>
>> Hi everyone,
>>
>> Just a quick reminder for the CG meetings this week.
>>
>> - a11y TF, Monday, Sept 10, 11am Eastern
>> - css TF, Monday, Sept 10, 12pm Eastern
>> - no CG meeting this week
>>
>> Best,
>> Peter.
>>
>
>

Re: [mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Neil Soiffer (soiffer@alum.mit.edu) • September 10, 2018 • Permalink

Apologies for missing the meeting today -- I don't seem to have the
meetings properly entered into my calendar and due to the time difference,
I don't see Peter's reminders until after I start work.

I have a question about what someone wrote on the Wiki:

>      a∧b∨c it is not clear the order precedence. Usually ∧ has precedence
> over ∨, but not always.
>

Can someone clarify (on the wiki) *when* it the normal precedence doesn't
hold. What surprised me when I first looked into notations and precedence
(20 years ago -- yikes!) was that although a symbols might have many
different meanings, the precedence relationships it has didn't seem to
change. I attributed that to people trying to avoid confusion when using
familiar notation for new functionality. Having '∨' have a different
precedence relative to '∧' in some cases seems very strange to me. But
mathematicians do strange things at times (especially logicians ;-).

    Neil


<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
Virus-free.
www.avg.com
<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <peter@krautzource.com>
wrote:

> Hi everyone,
>
> Just a quick reminder for the CG meetings this week.
>
> - a11y TF, Monday, Sept 10, 11am Eastern
> - css TF, Monday, Sept 10, 12pm Eastern
> - no CG meeting this week
>
> Best,
> Peter.
>

[mathonweb] reminder: meetings this week

Source: public-mathonwebpages@w3.org Mail Archives • Peter Krautzberger (peter@krautzource.com) • September 10, 2018 • Permalink

Hi everyone,

Just a quick reminder for the CG meetings this week.

- a11y TF, Monday, Sept 10, 11am Eastern
- css TF, Monday, Sept 10, 12pm Eastern
- no CG meeting this week

Best,
Peter.

RE: The User Input of Mathematics with Recognition Hints

Source: www-math@w3.org Mail Archives • Adam Sobieski (adamsobieski@hotmail.com) • September 04, 2018 • Permalink

Murray,

Thank you for indicating math braille.


Best regards,
Adam

________________________________
From: Murray Sargent <murrays@exchange.microsoft.com>
Sent: Monday, September 3, 2018 1:24:23 PM
To: Adam Sobieski; public-exercises-and-activities@w3.org; www-math@w3.org
Subject: RE: The User Input of Mathematics with Recognition Hints

You might also want to consider math braille<https://blogs.msdn.microsoft.com/murrays/2016/07/31/nemeth-braille-the-first-math-linear-format/>.

Cheers!
Murray

From: Adam Sobieski <adamsobieski@hotmail.com>
Sent: Monday, September 3, 2018 10:08 AM
To: public-exercises-and-activities@w3.org; www-math@w3.org
Subject: RE: The User Input of Mathematics with Recognition Hints

Educational Exercises and Activities Community Group,
Math Working Group,

Excellent news. The accessible user input of mathematics in HTML5 documents [1] is incubating at the Web Incubator CG (WICG): https://discourse.wicg.io/t/proposal-user-input-of-mathematics/2998<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdiscourse.wicg.io%2Ft%2Fproposal-user-input-of-mathematics%2F2998&data=02%7C01%7Cmurrays%40exchange.microsoft.com%7C3c3892fb854741f6e45608d611c00dbf%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636715913903002198&sdata=nM2CvtRvxsRfGgS41aPY3M2zj0k4VzOeBf%2BSkOH6iQk%3D&reserved=0> . Please show your interest and support there towards the user input of mathematics becoming a Web Platform WG deliverable.


Best regards,
Adam Sobieski

[1] https://www.w3.org/community/exercises-and-activities/wiki/User_Input_of_Mathematics<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.w3.org%2Fcommunity%2Fexercises-and-activities%2Fwiki%2FUser_Input_of_Mathematics&data=02%7C01%7Cmurrays%40exchange.microsoft.com%7C3c3892fb854741f6e45608d611c00dbf%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636715913903012207&sdata=lmpfwcSv7jdY4uanj%2BD4EVC%2BragSqHdP3BVK96CBFag%3D&reserved=0>

Image deleted "equation tree" in previous post by mailing list archiver

Source: www-math@w3.org Mail Archives • DJ Barrow (barrow_dj@yahoo.com) • September 04, 2018 • Permalink

Apologies, 
It can be found at
https//djbarrow.github.io/images/equation_tree.png

D. J.  Barrow, Engineer
+353861715438
barrow_dj@yahoo.com
web:https://djbarrow.github.io
blog:http://sinscienceandspirituality.blogspot.com 

hopefully a suggestion that will be looked into a little to simplify comprehension of complex equations.

Source: www-math@w3.org Mail Archives • D.J. Barrow (barrow_dj@yahoo.com) • September 04, 2018 • Permalink

Mathematic notation is complex, operator calculus is horrible & the only people who can read your average maths book is those with a memory that can cross reference a name of a constant with a letter,

HTML/pdf/Word/LATEX document standards. needs a mathematical standard that one can hover the mouse over an equation & it expands mathematical variables to there full name, also, if the equation was expanded as a tree ( i.e. no brackets ), on a full page rather than as compact as possible on a single line. One could display full names of mathematical variables otherwise impossible so one wouldn´t be wrecking their head trying to figure out what an equation is acually saying because you don´t have to remember 20 variables written down in that very terse mathematical doctorial thesis 3 pages ago, &, you can´t get your head around. This idea I name, an equation tree, see example below in bad ascii art.



This equation on a line without variable names shortened to fit look like
speed of light in a vacuum = ( speed of sound in air * 2 ) + speed of sound in water

a complex physics equation would take several lines fully expanded. Maybe it's an idea to have the equation tree only to pop up if you can't understand the equation in terse notation.


D.J. Barrow Linux kernel developer Mobile Ireland: +353-86-1715438website: https://djbarrow.github.io
blog:http://sinscienceandsprituality.blogspot.ie

RE: The User Input of Mathematics with Recognition Hints

Source: www-math@w3.org Mail Archives • Murray Sargent (murrays@exchange.microsoft.com) • September 03, 2018 • Permalink

You might also want to consider math braille<https://blogs.msdn.microsoft.com/murrays/2016/07/31/nemeth-braille-the-first-math-linear-format/>.

Cheers!
Murray

From: Adam Sobieski <adamsobieski@hotmail.com>
Sent: Monday, September 3, 2018 10:08 AM
To: public-exercises-and-activities@w3.org; www-math@w3.org
Subject: RE: The User Input of Mathematics with Recognition Hints

Educational Exercises and Activities Community Group,
Math Working Group,

Excellent news. The accessible user input of mathematics in HTML5 documents [1] is incubating at the Web Incubator CG (WICG): https://discourse.wicg.io/t/proposal-user-input-of-mathematics/2998<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdiscourse.wicg.io%2Ft%2Fproposal-user-input-of-mathematics%2F2998&data=02%7C01%7Cmurrays%40exchange.microsoft.com%7C3c3892fb854741f6e45608d611c00dbf%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636715913903002198&sdata=nM2CvtRvxsRfGgS41aPY3M2zj0k4VzOeBf%2BSkOH6iQk%3D&reserved=0> . Please show your interest and support there towards the user input of mathematics becoming a Web Platform WG deliverable.


Best regards,
Adam Sobieski

[1] https://www.w3.org/community/exercises-and-activities/wiki/User_Input_of_Mathematics<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.w3.org%2Fcommunity%2Fexercises-and-activities%2Fwiki%2FUser_Input_of_Mathematics&data=02%7C01%7Cmurrays%40exchange.microsoft.com%7C3c3892fb854741f6e45608d611c00dbf%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636715913903012207&sdata=lmpfwcSv7jdY4uanj%2BD4EVC%2BragSqHdP3BVK96CBFag%3D&reserved=0>

RE: The User Input of Mathematics with Recognition Hints

Source: www-math@w3.org Mail Archives • Adam Sobieski (adamsobieski@hotmail.com) • September 03, 2018 • Permalink

Educational Exercises and Activities Community Group,
Math Working Group,

Excellent news. The accessible user input of mathematics in HTML5 documents [1] is incubating at the Web Incubator CG (WICG): https://discourse.wicg.io/t/proposal-user-input-of-mathematics/2998 . Please show your interest and support there towards the user input of mathematics becoming a Web Platform WG deliverable.


Best regards,
Adam Sobieski

[1] https://www.w3.org/community/exercises-and-activities/wiki/User_Input_of_Mathematics

Re: MathOnWeb CG -- meeting minutes 2018-08-30

Source: public-mathonwebpages@w3.org Mail Archives • Volker Sorge (volker.sorge@gmail.com) • August 31, 2018 • Permalink

Ah, I see how you did it. I was desperately trying to put code into
the page without success... So only added a single link.
Well done! Thanks for all the work.

I added a bit to continuous fractions. I also have Inference Rules
running in MJ3, so I might just add a page to repo and link to it.

Best,
Volker
On Fri, 31 Aug 2018 at 18:39, Neil Soiffer <soiffer@alum.mit.edu> wrote:
>
> * Peter: as per actio, I created the wiki page discussed on Monday for a11y TF
>
> I filled in the wiki page with examples and some text and a few more forms. Unfortunately, the math isn't aligned well with the text, but it is the best I could do with the wiki.
>
>     Neil
>
>
> On Fri, Aug 31, 2018 at 1:44 AM, Peter Krautzberger <peter@krautzource.com> wrote:
>>
>> Hi everyone,
>>
>> Here are the minutes from the meeting on August 30.
>>
>> In the meeting, we decided to reduce the main meeting to a monthly one. So the next meeting of the full CG will be Sept 27 (but TFs continue to meet bi-weekly).
>>
>> Best,
>> Peter.
>>
>> # MathOnWeb CG 2018-08-30
>>
>> * Present: Peter, Neil, Dani, Kevin
>>   * regrets: Joanie, Volker, Charles
>> * Peter: as per actio, I created the wiki page discussed on Monday for a11y TF
>>   * I also created one for CSS TF as per the last meeting
>>     * prepping for tpac should be priority for the next few weeks
>>   * Neil: who's going?
>>     * Peter:  https://github.com/w3c/mathonwebpages/wiki/MathOnWeb-CG-@-TPAC-2018
>> * Dani: now that TFs meet, can we reduce the Thursday meetings?
>>   * once a month? less?
>>   * Neil: having a meeting would be good, e.g., I can't make the CSS TF meetings
>>   * => AGREED: 1 main meeting per month is enough right now
>> * Neil: does anyone know more about MathML related funding?
>>   * Sloan giving to NISO https://www.niso.org/niso-io/newsline/2018/08/newsline-august-2018?
>>   * => interesting news, not much info to be found, nobody had heard more
>> * Dani: on a11y. say we want to label something as fraction
>>   * with a dictionary, we have to make it open
>>   * but another question is navigating through an expression
>>   * we seem to mixing these and get confused over it
>>   * e.g. an role for fraction is a feature
>>   * but is not sufficient for what we want to do
>>     * e.g. aria-label overwrites entire accessible name
>>     * e.g. on the other hand aria-owns describes structure differntly
>>   * when talking to ARIA/APA we should separate those clearly
>>   * Peter: yes, I think some of Monday's meeting was already going in this direction
>>   * Neil: right, extracting the semantics even falls into two parts: inference and speech/etc generation, then there's navigation
>>
>>
>

Converting Microsoft Equation Editor Objects to OfficeMath

Source: Murray Sargent: Math in Office • MurrayS3 • August 31, 2018 • Permalink

As discussed in the post Editing equations created using the Microsoft Equation Editor, the Microsoft Equation Editor 3.0 (MEE) was removed from Office installations because it has security problems and no maintenance. Microsoft doesn’t have access to the MEE source code and MEE’s author, Design Science, doesn’t maintain it, instead offering the more powerful, upward-compatible MathType program. Provided the MT Extra font is installed, MEE OLE objects display correctly, but they cannot be edited unless the user installs MathType or converts them to Office native math zones (OfficeMath). This post describes the conversion facility that ships with Office 365. The feature sets of MEE, MathType and OfficeMath are compared in the post Equation-Editor OfficeMath Feature Comparison and Other Office Math Editing Facilities. The converter can convert most MEE and MathType OLE objects to OfficeMath. Some equation objects cannot be converted, e.g., long division, since OfficeMath doesn’t have a counterpart. First, let’s see how the converter works in PowerPoint, Excel, and Word, then let’s check out the functions a program can call to perform conversions, and lastly, let’s interpret an MEE “Equation Native” binary data stream. Please let us know your thoughts via Send A Smile with #MEEConverter in the text.

File Format Prerequisite

Conversion to OfficeMath is only enabled for program modes that support the OMML (Office Math Markup Language) file format. If a file is opened in “Compatibility Mode”, equation objects in the file may not be directly convertible to OfficeMath. Word added OMML support in Word 2007 and PowerPoint and Excel added it in Office 2010. The old doc, ppt, and xls file formats do not support OMML. To convert equation objects in such files, first save them as the corresponding docx, pptx, and xlsx files using the Save As menu option. Then you can click on an equation object and get a menu/dialog that offers “Convert Equation to Office Math” and an option to “Apply to all equations”.

Office Equation Object Conversion

PowerPoint displays OLE objects on a slide wherever you put them. The objects are not embedded in the text of text boxes and hence don’t flow with text. For example, if you line up an equation object with text in a text box and change the text size, the text moves, but the equation object doesn’t move since it’s not part of the text. This differs from Word, for which OLE objects are embedded in the text and therefore flow with text changes.

The equation-editor converter converts OLE objects to native math (OfficeMath) text. To put the OfficeMath for a converted object onto a PowerPoint slide, the OfficeMath is stored in its own OfficeArt text box, which has the same dimensions as the original OLE object. People often position a set of equation objects to lay out equations nicely. Ideally all these objects would end up properly aligned in a single text box. But that’s a tricky recognition task and it isn’t handled by the converter. Users may want to do some cutting and pasting to get optimal results. The same approach is used for converting MEE objects in Excel.

In Word, equation objects are embedded in the text and the corresponding OfficeMath text replaces the objects in that text.  So, equation conversion in Word doesn’t have object/text alignment problems, although line and page breaks may change due to the use of different fonts. OfficeMath requires a math font for characters supported by a math font, while MEE and MathType use a collection of non-math fonts that can be customized by the user.

Text Size of Converted Equations

The MEE object Equation-Native binary data (described in later sections) includes relative font sizes but doesn’t provide an overall default font size. For example, if you resize an equation object in PowerPoint, the Equation-Native binary data doesn’t change nor do the text sizes in the Windows metafile used to display the object. If the converted math text is too large for its text box, PowerPoint decreases the font size to fit. In any event, the converted math text typically has a different size from that in the original OLE object.

Fixups

There are two kinds of fixups performed by the converter: 1) those handling differences in the math models as described in Integrands, Summands, and Math Function Arguments and Subscript and Superscript Bases, and 2) those dealing with equation object errors that don’t affect the object display significantly but change the display of the converted math text. For example, in OfficeMath, empty numerators, denominators, subscripts, superscripts, etc., display the place-holder character ⬚. Since the OLE objects don’t display such a character, the converter fixes up equations by removing empty subscripts and converting left subscripts with no bases into normal (right) subscripts. Similarly, if a math function name like “min” doesn’t have an argument, the converter treats the function name as ordinary text, rather than as a function-apply object with an empty base. In testing PowerPoint presentations, we found many such errors including an extreme case of an MEE subscript object with a subscript consisting of a “pile” of four empty lines. The converted math text shows a column (equation array) of four ⬚’s although the original object shows nothing. It seems reasonable to have the user delete errors that are that complicated. MEE and MathType use the deprecated codes U+2329 and U+232A for the wide-angle brackets ⟨ (U+27E8) and ⟩ (U+27E9), respectively. The converter replaces the former pair by the latter pair. It also changes the upper limit construction for ≝ into the single character (U+225D).

APIs

Now things get more technical. The converter is implemented as part of RichEdit and uses the same TOM interfaces as the UnicodeMath/LaTeX/speech/braille build up/down facilities. The Office RichEdit dll (riched20.dll) exports three conversion functions: ConvertEquationFromStorage() converts the object given by an IStorage interface, ConvertEquationFromOleStream() converts the object given by the OLESTREAM Get() method (prototype defined in ole2.h), and ConvertEquationFromStdVector() converts the equation binary data in the “Equation Native” stream. These functions don’t call operating-system OLE functions; hence they can be used on all major platforms. The prototypes for the functions are

HRESULT ConvertEquationFromOleStream(
    ITextRange2 * prg,
    ITextStrings2 * pstrs,
    OLESTREAM *  poleStream,     // OLE stream to read from
    BYTE         bVersion)       // Design Science MathType version #
 
HRESULT ConvertEquationFromStorage(
    ITextRange2 * prg,           // Range for inserting result
    ITextStrings2 * pstrs,       // Rich-text string stack
    IStorage *     pstg)         // IStorage for OLE math object

HRESULT ConvertEquationFromStdVector(
    ITextRange2 *       prg,
    ITextStrings2 *     pstrs,
    std::vector<BYTE> & EquationNative, // "Equation Native" binary stream
    BYTE                bVersion)       // Design Science version # (3-EE3, 5-MathType)

The interface ITextStrings2 is defined in the Office tom.h (eventually it’ll be in the Windows tom.h) and derives from ITextStrings. It adds the method

ITextStrings2::Rotate(LONG iString)

ITextStrings2::Rotate(-2) reorders the Design Science N-ary arguments to put the naryand (integrand, summand, …) third instead of first. ITextStrings2::Rotate(-1) is the same as ITextStrings::Swap() and swaps the top two strings. If the Type argument of ITextStrings::EncodeFunction() has the tomTeXStyleIsTextColor flag set, the TeXStyle argument has the text color instead of the TeXStyle. The TeXStyle isn't used by the converter since it’s implied by context (although it is stored in the OLE object binary data).

ConvertEquationFromStorage() calls IStorage::OpenStream(L”Equation Native”, …) to retrieve the Design Science OLE object’s “Equation Native” stream and then calls the converter to create the corresponding native math zones.

ConvertEquationFromOleStream() reads a Design Science object's compound file format, defragments it, retrieves the “Equation Native” stream, and calls the converter to create the corresponding math zones.

ConvertEquationFromStdVector() converts the "Equation Native" binary stream to a built-up Office math zone. This function is handy for unit tests. Enter with the EquationNative std::vector<BYTE> starting with the byte following the two "Equation Native" stream headers. The “Equation Native” binary format is illustrated in the next section.

Equation Native Stream

The Design Science OLE object "Equation Native" stream contains the MTEF binary data for a MathType or MEE object. The MTEF data consists of a 28-byte equation-OLE header, a version header (5 bytes for MEE and 12 bytes for MathType) followed by the records for the equation. Container records (rcdLINE, rcdTMPL, rcdPILE, rcdMATRIX) can contain other records including themselves and are terminated by the end record rcdEND. For full documentation, see MathType's Equation Format (MTEF) in the MathType SDK (http://www.dessci.com/en/reference/sdk/).

The following table illustrates the Equation Editor 3.0 binary records for the equation

The two headers in the Equation-Native stream are omitted. Putting the binary into a std::vector<BYTE> and passing it to ConvertEquationFromStdVector(), you insert this equation into the text. Be sure to convert the ASCII hex characters to binary, two per byte with no intervening spaces. Note that the integrand precedes the integral limits. In OfficeMath, the integrand follows the limits, hence the need for ITextStrings2::Rotate().

binary meaning
0a
01
030e0000
01
02883100
00
01
02883200 0284c003
00
00
03150200
01
030e0000
01 12836400 0284b803 00
01
12836100 02862b00 12836200
12827300 12826900 12826e00 0284b803
00
00
00
0b
01 02883000 00
01 02883200 0284c003 00
0d
02862b22
00
0a
02863d00
030e0000
01 02883100 00
01
030d0000
01
12836100
030f0000
0b
11
01 02883200 00
00
0a
02861222 12836200
030f0000 0b 11 01 02883200 00 00
00
11
00
00
00
00
<normal size/>
<line>
  <fraction>
    <line> (numerator)
      1
    </line>
    <line> (denominator)
      2𝜋
    </line>
  </fraction>
  <integral>
    <line> (integrand)
      <fraction>
        <line>𝑑𝜃</line>
        <line>
          𝑎 + 𝑏
          sin 𝜃
        </line>
      </fraction>
    </line>
    <script size/>
    <line>0</line> (lower limit)
    <line>2𝜋</line> (upper limit)
    <symbol size/>
    ∫ (character)
  </integral>
  <normal size/>
  =
  <fraction>
    <line>1</line> (numerator)
    <line> (denominator)
      <root>
        <line>
          𝑎
          <sup>
          <sup size/>
            <line/> (null subscript)
            <line>2</line>
          </sup>
          <normal size/>
          − 𝑏
          <sup><sup size/><line/><line>2</line></sup>
        </line> (end radicand)
        <line/> (no degree, i.e., square root)
      </root>
    </line>
  </fraction>
</line>

 

Re: MathOnWeb CG -- meeting minutes 2018-08-30

Source: public-mathonwebpages@w3.org Mail Archives • Neil Soiffer (soiffer@alum.mit.edu) • August 31, 2018 • Permalink

* Peter: as per actio, I created the wiki page discussed on Monday for a11y
TF

I filled in the wiki page
<https://github.com/w3c/mathonwebpages/wiki/[a11y-TF]-ambiguous-notation>with
examples and some text and a few more forms. Unfortunately, the math isn't
aligned well with the text, but it is the best I could do with the wiki.

    Neil


On Fri, Aug 31, 2018 at 1:44 AM, Peter Krautzberger <peter@krautzource.com>
wrote:

> Hi everyone,
>
> Here are the minutes from the meeting on August 30.
>
> In the meeting, we decided to reduce the main meeting to a monthly one. So
> the next meeting of the full CG will be Sept 27 (but TFs continue to meet
> bi-weekly).
>
> Best,
> Peter.
>
> # MathOnWeb CG 2018-08-30
>
> * Present: Peter, Neil, Dani, Kevin
>   * regrets: Joanie, Volker, Charles
> * Peter: as per actio, I created the wiki page discussed on Monday for
> a11y TF
>   * I also created one for CSS TF as per the last meeting
>     * prepping for tpac should be priority for the next few weeks
>   * Neil: who's going?
>     * Peter:  https://github.com/w3c/mathonwebpages/wiki/MathOnWeb-
> CG-@-TPAC-2018
> * Dani: now that TFs meet, can we reduce the Thursday meetings?
>   * once a month? less?
>   * Neil: having a meeting would be good, e.g., I can't make the CSS TF
> meetings
>   * => AGREED: 1 main meeting per month is enough right now
> * Neil: does anyone know more about MathML related funding?
>   * Sloan giving to NISO https://www.niso.org/niso-io/
> newsline/2018/08/newsline-august-2018?
>   * => interesting news, not much info to be found, nobody had heard more
> * Dani: on a11y. say we want to label something as fraction
>   * with a dictionary, we have to make it open
>   * but another question is navigating through an expression
>   * we seem to mixing these and get confused over it
>   * e.g. an role for fraction is a feature
>   * but is not sufficient for what we want to do
>     * e.g. aria-label overwrites entire accessible name
>     * e.g. on the other hand aria-owns describes structure differntly
>   * when talking to ARIA/APA we should separate those clearly
>   * Peter: yes, I think some of Monday's meeting was already going in this
> direction
>   * Neil: right, extracting the semantics even falls into two parts:
> inference and speech/etc generation, then there's navigation
>
>
>

MathOnWeb CG -- meeting minutes 2018-08-30

Source: public-mathonwebpages@w3.org Mail Archives • Peter Krautzberger (peter@krautzource.com) • August 31, 2018 • Permalink

Hi everyone,

Here are the minutes from the meeting on August 30.

In the meeting, we decided to reduce the main meeting to a monthly one. So
the next meeting of the full CG will be Sept 27 (but TFs continue to meet
bi-weekly).

Best,
Peter.

# MathOnWeb CG 2018-08-30

* Present: Peter, Neil, Dani, Kevin
  * regrets: Joanie, Volker, Charles
* Peter: as per actio, I created the wiki page discussed on Monday for a11y
TF
  * I also created one for CSS TF as per the last meeting
    * prepping for tpac should be priority for the next few weeks
  * Neil: who's going?
    * Peter:
https://github.com/w3c/mathonwebpages/wiki/MathOnWeb-CG-@-TPAC-2018
* Dani: now that TFs meet, can we reduce the Thursday meetings?
  * once a month? less?
  * Neil: having a meeting would be good, e.g., I can't make the CSS TF
meetings
  * => AGREED: 1 main meeting per month is enough right now
* Neil: does anyone know more about MathML related funding?
  * Sloan giving to NISO
https://www.niso.org/niso-io/newsline/2018/08/newsline-august-2018?
  * => interesting news, not much info to be found, nobody had heard more
* Dani: on a11y. say we want to label something as fraction
  * with a dictionary, we have to make it open
  * but another question is navigating through an expression
  * we seem to mixing these and get confused over it
  * e.g. an role for fraction is a feature
  * but is not sufficient for what we want to do
    * e.g. aria-label overwrites entire accessible name
    * e.g. on the other hand aria-owns describes structure differntly
  * when talking to ARIA/APA we should separate those clearly
  * Peter: yes, I think some of Monday's meeting was already going in this
direction
  * Neil: right, extracting the semantics even falls into two parts:
inference and speech/etc generation, then there's navigation

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