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The sad state of PDF-Accessibility of LaTex Documents (2016)

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Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#51

Post by jimhefferon »

ketzu wrote: post #46
mci wrote: post #35

1. Needs (2016) in the title. 2. Even by 2016, pdfTeX had been largely superseded by LuaTeX. 3. The author bizzarely links to "the mess" of the literate source of TeX the program as a WEB file rather than as a typeset document. 4. AIUI, the source code of the TeX engine has nothing/very little to do with adding tags to PDFs, which it is the job for LaTeX packages. Admittedly, understanding and writing their source co…

> 2. Even by 2016, pdfTeX had been largely superseded by LuaTeX. Is that true? My experience was that pdftex is by far the most used one, but while thinking about it, I noticed I have zero data to back that up.

The overwhelming majority of people writing today use pdflatex. But at this point lualatex is pretty fast, and is starting to accumlate packages that leverage it to do good things. It is starting to build momentum.

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#52

Post by jimhefferon »

vehemenz wrote: post #33
jimktrains2 wrote: post #14

Earlier quoted context omitted.

Not even considering the math formatting, Html is still lacking good footnotes, bibliographies, glossary generation, index generation, and table of context generation. Browsers also render things atrociously compared to a latex pdf.

There are third-party tools that do all of this. A LaTeX-generated PDF does not render correctly at all for a blind user.

> There are third-party tools that do all of this.

The things that today do this will be all gone in ten years, or replaced with other things that will in turn be replaced ... LaTeX has been here for a long time, and has been strikingly stable.

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#53

Post by vincent-manis »

hugh-avherald wrote: post #15
konjin wrote: post #3

>Take your average computer science graduate from the last ten years. Do you think anyone would be remotely able to understand what is going on there? Yes, you literally read the literate program of TeX and understand what's going on: http://brokestream.com/tex.pdf I had never learned Pascal but I've managed to edit and compile TeX successfully, and it was easier than trying to understand any of my own non-literate p…

It does seem that the OP constructs a bit of a strawman by claiming TeX's source code is too complicated for an average computer science graduate. I doubt even the top 5% of computer graduates could more readily understand the source code of most common programs.

Well, Knuth's programming style is idiosyncratic, to say the least. But in the early 80s, in advance of the publication of The TeXBook, I learned enough TeX from reading the literate source for TeX to put together a 100-page software manual.

I don't really agree with Knuth's version of literate programming, but one can hardly fault the TeX source for being unreadable.

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#54

Post by romwell »

choeger wrote: post #48

The thing is: LaTeX might try hard to look like a declarative language for structured documents, but it is not. It is a set of TeX macros. And TeX is a type setting system. There is no good reason to put the accessibility into the type setting. Instead, use a declarative (e.g., any markup) language, translate that a) to (LaTeX) and b) to accessibility annotations and then combine the two results. Problem solved. Unfo…

Why not simply augment LaTex with PDF tags which would be inserted manually, in the process of typesetting?

Something like:

    \pdftag{blah}
Common packages could then generate these tags, and very few modifications of TeX source would be needed.

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#55

Post by Tainnor »

JadeNB wrote: post #44
Tainnor wrote: post #41

Earlier quoted context omitted.

You're skimping on some of the complexity by equating a definition with a particular way of computing it, but that's completely inadequate for mathematics, as there are many things we can't compute (either in theory or in practice). In particular, you definition of integral assumes that integrable functions always have an antiderivative, which is wrong.

> In particular, you definition of integral assumes that integrable functions always have an antiderivative, which is wrong. I was objecting at the same time as you were, but I don't think this is the right objection. It's true that not every integrable function has an elementary anti-derivative, but every integrable function f does have an anti-derivative F, at least in the sense that F is almost everywhere differen…

If you say "at least in the sense that F is almost everywhere differentiable", you're already redefining "anti-derivative" to some extent, I feel. But this is just arguing over semantics. Even then, I think your claim that every integrable function has a "generalized antiderivative" is also only true for the Riemann integral. The Dirichlet function is Lebesgue integrable, but it doesn't have an antiderivative even in this weaker sense.[^1] And mathematicians generally prefer the Lebesgue integral.

I think the more important insight here is that integration fundamentally isn't defined through the anti-derivative, and that the two notions are actually related is a deep theorem, rather than just a definition.

And the fact that non-elementary antiderivatives exist is interesting in theory, but in practice you can't use them directly for anything. In particular, in practical situations you will often use numerical methods to integrate a function which will not be based on any notion of anti-derivative at all.

[^1] Edit: I think I was wrong here. If you take the function identically zero, then its derivative is identically zero and as such equal to the Dirichlet function almost everywhere. So this is not a counterexample. I still think it's weird to call than an "antiderivative" though.

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#56

Post by realityking »

jfk13 wrote: post #18
Mediterraneo10 wrote: post #13

Earlier quoted context omitted.

It wasn’t because mathematicians were reluctant to change that math in HTML didn't take off. Rather, it was because browser developers were loathe to implement and maintain the enormous and complex pile of code that is MathML, and they said "Why should we, if you mathematicians already have LaTeX?" [0] [0] https://en.wikipedia.org/wiki/MathML#Browser_support

Firefox has had MathML support for a long time. Complain to Apple and Google (and vote with your browsing activity, by using the browser that is less driven by commercial considerations).

Safari has supported MathML since 2011. Though apparently the implementation is somewhat buggy.

The real issue is the lack of MathML support by Chrome (and until recently, Edge)

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#57

Post by konjin »

Tainnor wrote: post #41
konjin wrote: post #19

Earlier quoted context omitted.

1 + 1 = 2 Aren't formulas easy to insert in plain text? The problem with maths notation is that it was invented by sighted people for sighted people as a short hand for very complex ideas, which at the time weren't fully understood. If you want to type equations use s-expressions, the clarity you get from saying what you mean is astonishing. (define integral (lambda (function) ;; Implementation of Risch algorithm lef…

You're skimping on some of the complexity by equating a definition with a particular way of computing it, but that's completely inadequate for mathematics, as there are many things we can't compute (either in theory or in practice). In particular, you definition of integral assumes that integrable functions always have an antiderivative, which is wrong.

I find it odd that you pretend a meta-mathematical question is a mathematical one.

You are dismissing constructivism as not mathematics, and you ignore that the halting problem is a way to deal with a class of results which include non-existence proofs by running an algorithm forever.

I can easily create calculations that will never return results which classical mathematics say are impossible by the simple fact they never return any results at all.

The Risch algorithm being a complex example, finding the square root of two in the rational number domain being a simple one. I can still deal with them as though they return results in all calculations though, without the need for baroque semi-mystical notation. Unless you want to claim some sort of divine human essence not present in Turing Machines and Lambda Calculus which lets us transcend their computational capabilities?

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#58

Post by rmbeard »

throw0101a wrote: post #50
HarryHirsch wrote: post #22

Earlier quoted context omitted.

Back in the day we had engineers writing documents from markup. We called them typesetters. It was a qualified job, you don't expect the task to be something Joe Random could to with 6 weeks of training.

> Back in the day we had engineers writing documents from markup. Back in the day secretaries were creating electronic documents with troff and nroff: > The first version of Unix was developed on a PDP-7 which was sitting around Bell Labs. In 1971 the developers wanted to get a PDP-11 for further work on the operating system. In order to justify the cost for this system, they proposed that they would implement a docu…

OP, here. It's not that long ago, I've used troff myself. Or maybe it was that long ago, but it just seems like yesterday.

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#59

Post by Tainnor »

konjin wrote: post #57
Tainnor wrote: post #41

Earlier quoted context omitted.

You're skimping on some of the complexity by equating a definition with a particular way of computing it, but that's completely inadequate for mathematics, as there are many things we can't compute (either in theory or in practice). In particular, you definition of integral assumes that integrable functions always have an antiderivative, which is wrong.

I find it odd that you pretend a meta-mathematical question is a mathematical one. You are dismissing constructivism as not mathematics, and you ignore that the halting problem is a way to deal with a class of results which include non-existence proofs by running an algorithm forever. I can easily create calculations that will never return results which classical mathematics say are impossible by the simple fact they…

I literally don't understand what the hell you are talking about.

But this has nothing to do with constructivism. Even if you only allow constructive definitions and proofs, there is still the world of a difference between the definition of an integral and the result you get from evaluating it.

Yeah, sure, in theory you can represent an integral as a function that takes another function and two boundary points and returns a value...

But first, it may not be possible to determine the value of the integral exactly because there is no known method of doing so (the Risch algorithm, apart from it basically being so complex that it's implemented almost nowhere fully, only works for elementary functions!).

And second, if integrals are "just functions", you lose the ability to manipulate them according to known theorems, e.g. additivity, triangle inequality, Cauchy-Schwarz, convergence theorems, ...

So yeah, here's where I get the feeling that some people should do some more maths and spend good parts of their days proving theorems and playing with definitions before they start complaining about how dumb its language is.

Re: The sad state of PDF-Accessibility of LaTex Documents (2016)

#60

Post by konjin »

Tainnor wrote: post #59
konjin wrote: post #57

Earlier quoted context omitted.

I find it odd that you pretend a meta-mathematical question is a mathematical one. You are dismissing constructivism as not mathematics, and you ignore that the halting problem is a way to deal with a class of results which include non-existence proofs by running an algorithm forever. I can easily create calculations that will never return results which classical mathematics say are impossible by the simple fact they…

I literally don't understand what the hell you are talking about. But this has nothing to do with constructivism. Even if you only allow constructive definitions and proofs, there is still the world of a difference between the definition of an integral and the result you get from evaluating it. Yeah, sure, in theory you can represent an integral as a function that takes another function and two boundary points and re…

>So yeah, here's where I get the feeling that some people should do some more maths and spend good parts of their days proving theorems and playing with definitions before they start complaining about how dumb its language is.

Some people have a PhD in mathematical physics and wrote the higher function code of axiom. I guess those people would be difficult to understand for non-experts.

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