Comments on: Math, fonts, and HTML http://bit-player.org/2009/math-fonts-and-html An amateur's outlook on computation and mathematics. Thu, 17 May 2012 09:54:48 +0000 http://wordpress.org/?v=2.6.3 By: brian http://bit-player.org/2009/math-fonts-and-html#comment-2142 brian Mon, 11 May 2009 23:32:43 +0000 http://bit-player.org/?p=280#comment-2142 @shinn: Perhaps I misunderstand your point, but I think the situation is just the opposite. Under the present regime, a given web page can be displayed in many different fonts, depending on which ones happen to be installed on each client machine. Fonts embedded within a page would display the same everywhere. @shinn:

Perhaps I misunderstand your point, but I think the situation is just the opposite. Under the present regime, a given web page can be displayed in many different fonts, depending on which ones happen to be installed on each client machine. Fonts embedded within a page would display the same everywhere.

]]> By: shinn http://bit-player.org/2009/math-fonts-and-html#comment-2141 shinn Mon, 11 May 2009 19:39:05 +0000 http://bit-player.org/?p=280#comment-2141 I could think of only one reason why fonts are not rendered embeddable: i.e. having thousands of fonts out inhibits any chance of standardizing the output we get across different browsers and platforms. I could think of only one reason why fonts are not rendered embeddable: i.e. having thousands of fonts out inhibits any chance of standardizing the output we get across different browsers and platforms.

]]> By: Alon Amit http://bit-player.org/2009/math-fonts-and-html#comment-1986 Alon Amit Fri, 27 Feb 2009 22:06:05 +0000 http://bit-player.org/?p=280#comment-1986 @Brian, @Claire - thanks to both of you. Interesting point about RSS, Brian. I was leaning towards just using Wordpress for my blog, which includes a server-side implementation of LaTeX as I'm sure you know, but I'm intrigued by certain aspects of jsMath. Thanks very much for sharing your perspective. @Brian, @Claire - thanks to both of you.

Interesting point about RSS, Brian. I was leaning towards just using Wordpress for my blog, which includes a server-side implementation of LaTeX as I’m sure you know, but I’m intrigued by certain aspects of jsMath. Thanks very much for sharing your perspective.

]]> By: brian http://bit-player.org/2009/math-fonts-and-html#comment-1985 brian Fri, 27 Feb 2009 20:07:47 +0000 http://bit-player.org/?p=280#comment-1985 <span class="tex2math_ignore">@Alon: As you have surely inferred, I have enabled the use of $$ ... $$ as a marker for display math, since I think it unlikely anyone will need that particular sequence of symbols for other purposes. But I've disabled $ ... $ for inline math, so that we don't have to escape every dollar sign. As Claire pointed out -- or tried to point out -- \( ... \) and \[ ... \] also work. But, as Claire's comment illustrates, it's a bit of a bother to talk about these markers in a venue where jsMath is eagerly trying to interpret them. I thought that a simple backslash escape would do the trick, but apparently not. I fixed Claire's post and this one by adding a class="tex2math_ignore" declaration, which is not exactly obvious. I remain undecided about the whole jsMath experiment, and I may yet switch to a server-side solution. As you point out, jsMath doesn't work in the comment preview window, but then I'm not ecstatic about the preview function anyway. More serious, it doesn't work in RSS readers, and I don't think it ever will. </span> @Alon: As you have surely inferred, I have enabled the use of $$ … $$ as a marker for display math, since I think it unlikely anyone will need that particular sequence of symbols for other purposes. But I’ve disabled $ … $ for inline math, so that we don’t have to escape every dollar sign. As Claire pointed out — or tried to point out — \( … \) and \[ ... \] also work.

But, as Claire’s comment illustrates, it’s a bit of a bother to talk about these markers in a venue where jsMath is eagerly trying to interpret them. I thought that a simple backslash escape would do the trick, but apparently not. I fixed Claire’s post and this one by adding a class=”tex2math_ignore” declaration, which is not exactly obvious.

I remain undecided about the whole jsMath experiment, and I may yet switch to a server-side solution. As you point out, jsMath doesn’t work in the comment preview window, but then I’m not ecstatic about the preview function anyway. More serious, it doesn’t work in RSS readers, and I don’t think it ever will.

]]> By: brian http://bit-player.org/2009/math-fonts-and-html#comment-1984 brian Fri, 27 Feb 2009 19:48:00 +0000 http://bit-player.org/?p=280#comment-1984 @Dave Richeson: Thanks for posting that. As another ongoing thread on this site makes clear, I do have trouble getting numbers right, and apparently the difficulty extends all the way down to +1 and –1. @Dave Richeson: Thanks for posting that. As another ongoing thread on this site makes clear, I do have trouble getting numbers right, and apparently the difficulty extends all the way down to +1 and –1.

]]> By: Dave Richeson http://bit-player.org/2009/math-fonts-and-html#comment-1983 Dave Richeson Fri, 27 Feb 2009 13:38:10 +0000 http://bit-player.org/?p=280#comment-1983 Thank you for the <a href="http://www.americanscientist.org/issues/pub/2009/3/writing-math-on-the-web" rel="nofollow">interesting article</a> in the American Scientist. There is a mathematical typo in it, however. In the <a href="http://www.americanscientist.org/include/popup_fullImage.aspx?key=68H2YoK0A2s35fyftaCffUWpcXjrNyozzbGlQTSVmSJgqj2hg9Qtsw==" rel="nofollow">image on page 3</a> (on the web version) you have a sign error in Euler's identity; (let's see if this Latex works) $$e^{i\pi}-1=0$$ should be $$e^{i\pi}+1=0.$$ Thank you for the interesting article in the American Scientist. There is a mathematical typo in it, however. In the image on page 3 (on the web version) you have a sign error in Euler’s identity; (let’s see if this Latex works) $$e^{i\pi}-1=0$$ should be $$e^{i\pi}+1=0.$$

]]> By: Claire http://bit-player.org/2009/math-fonts-and-html#comment-1981 Claire Thu, 26 Feb 2009 22:37:01 +0000 http://bit-player.org/?p=280#comment-1981 @Alon <span class="tex2math_ignore">By default, you can't use the $ delimiters unless you tweak a setting in the main script (otherwise you'd have people complaining that their money references caused their pages to break). Instead, jsMath uses \( \) for inline math and the standard LaTeX \[ \] for display math.</span> @Alon

By default, you can’t use the $ delimiters unless you tweak a setting in the main script (otherwise you’d have people complaining that their money references caused their pages to break). Instead, jsMath uses \( \) for inline math and the standard LaTeX \[ \] for display math.

]]> By: Alon Amit http://bit-player.org/2009/math-fonts-and-html#comment-1979 Alon Amit Thu, 26 Feb 2009 21:01:24 +0000 http://bit-player.org/?p=280#comment-1979 Brian - thanks for very interesting posts and particularly for pointing me in the direction of jsmath, which looks like a very interesting option for math blogging. If I understand correctly, once you install it along with the tex2math plugin, both you (the author) and users can embed math within the standard $\LaTeX$ delimiters... Is that the case? I hope you don't mind that I'm hijacking this thread, and this post - in fact, this very paragraph - to quickly check that ;-) $$ e^{2\pi/5} (\sqrt{\varphi \sqrt{5}} - \varphi) = \frac{1}{1+\frac{e^{-2\pi}}{1+\frac{e^{-4\pi}}{1+\ldots}}} $$ (Note: This doesn't seem to work in preview, which I guess makes sense, but it does make it harder for users to check their code.) Brian - thanks for very interesting posts and particularly for pointing me in the direction of jsmath, which looks like a very interesting option for math blogging.

If I understand correctly, once you install it along with the tex2math plugin, both you (the author) and users can embed math within the standard $\LaTeX$ delimiters… Is that the case? I hope you don’t mind that I’m hijacking this thread, and this post - in fact, this very paragraph - to quickly check that ;-)
$$
e^{2\pi/5} (\sqrt{\varphi \sqrt{5}} - \varphi) =
\frac{1}{1+\frac{e^{-2\pi}}{1+\frac{e^{-4\pi}}{1+\ldots}}}
$$

(Note: This doesn’t seem to work in preview, which I guess makes sense, but it does make it harder for users to check their code.)

]]> By: Eamon Costello http://bit-player.org/2009/math-fonts-and-html#comment-1968 Eamon Costello Tue, 24 Feb 2009 14:24:44 +0000 http://bit-player.org/?p=280#comment-1968 Oh hey it just worked! I entered two dollar signs then 4^2 then two dollar signs Oh hey it just worked! I entered
two dollar signs then 4^2 then two dollar signs

]]> By: Eamon Costello http://bit-player.org/2009/math-fonts-and-html#comment-1967 Eamon Costello Tue, 24 Feb 2009 13:30:10 +0000 http://bit-player.org/?p=280#comment-1967 We use Moodle to each distance ed students (www.oscail.ie). Moodle has a nice feature that allows users to enter TEX fragments into discussion forums and render them as mathematical markup. It gets around the font issue by doing the work on the sever and rendering the expression as an image. So I go into a discussion forum and enter: "What is the answer to $$ 4 ^2 $$." This come out the other end as image embedded right within the text so you would actually think it is done in font. Moreover I can click on the image and to reveal the TEX code which I can copy and paste to continue the conversation (that is expressions are copyable and modifiable). - Eamon We use Moodle to each distance ed students (www.oscail.ie).
Moodle has a nice feature that allows users to enter TEX fragments into discussion forums and render them as mathematical markup.
It gets around the font issue by doing the work on the sever and rendering the expression as an image.
So I go into a discussion forum and enter:
“What is the answer to $$ 4 ^2 $$.”
This come out the other end as image embedded right within the text so you would actually think it is done in font. Moreover I can click on the image and to reveal the TEX code which I can copy and paste to continue the conversation (that is expressions are copyable and modifiable).

- Eamon

]]> By: Claire http://bit-player.org/2009/math-fonts-and-html#comment-1959 Claire Wed, 18 Feb 2009 23:14:32 +0000 http://bit-player.org/?p=280#comment-1959 @brian Yes, it's true -- fonts contain an "embedding bit" that can be set to on or off. Most commericial applications (e.g., Adobe Acrobat) read and respect that bit, and won't include fonts that say you can't embed them. I'm not sure how well-respected the embedding bit is by FOSS tools. Leaving the technical issues aside, fonts, like other software, are governed by software license agreements that may restrict their legal usage with or without technical limitations. Adobe happens to have <a href="http://www.adobe.com/aboutadobe/antipiracy/fonts.html" rel="nofollow">quite liberal licensing for their fonts</a> (no doubt in conjunction with their creation of PDF), so for most Adobe fonts you can embed them in PDF with no issues. But <a href="http://www.fontshop.com/support/licenses/" rel="nofollow">other type foundries licenses</a> vary. (There are links to a bunch of licenses there; Emigre is one license with a separate embedding agreement (and fees); a couple of others from that list with restrictions are Elsner+Flake and LucasFonts.) The license restrictions on embedding can range from "never, ever", to "only if there's no way someone can extract any of the font software" (which basically means never), to "only if the document can't be edited", to "sure, with an additional fee", to "it's okay", and anything a lawyer can imagine and put into words. I'm very happy with some of Adobe's fonts and use them with TeX to generate documents for my own use, for my website, and for my employer's website. But the embedding ban has stopped me from buying a number of fonts that I really like and would otherwise love to own -- if I can't typeset my resume and put it on my website, I'm just not going to buy the font. @brian

Yes, it’s true — fonts contain an “embedding bit” that can be set to on or off. Most commericial applications (e.g., Adobe Acrobat) read and respect that bit, and won’t include fonts that say you can’t embed them. I’m not sure how well-respected the embedding bit is by FOSS tools.

Leaving the technical issues aside, fonts, like other software, are governed by software license agreements that may restrict their legal usage with or without technical limitations. Adobe happens to have quite liberal licensing for their fonts (no doubt in conjunction with their creation of PDF), so for most Adobe fonts you can embed them in PDF with no issues. But other type foundries licenses vary. (There are links to a bunch of licenses there; Emigre is one license with a separate embedding agreement (and fees); a couple of others from that list with restrictions are Elsner+Flake and LucasFonts.)

The license restrictions on embedding can range from “never, ever”, to “only if there’s no way someone can extract any of the font software” (which basically means never), to “only if the document can’t be edited”, to “sure, with an additional fee”, to “it’s okay”, and anything a lawyer can imagine and put into words.

I’m very happy with some of Adobe’s fonts and use them with TeX to generate documents for my own use, for my website, and for my employer’s website. But the embedding ban has stopped me from buying a number of fonts that I really like and would otherwise love to own — if I can’t typeset my resume and put it on my website, I’m just not going to buy the font.

]]> By: brian http://bit-player.org/2009/math-fonts-and-html#comment-1957 brian Wed, 18 Feb 2009 21:53:45 +0000 http://bit-player.org/?p=280#comment-1957 <blockquote>Unicode has all the math symbols. Why can’t you use these for math presentation?</blockquote> The Unicode standard offers code points for a very rich assortment of mathematical characters. It's a big step in the right direction. But just because someone has installed "Unicode fonts" on a machine doesn't mean there are glyphs available for all those code points. (At <a href="http://www.alanwood.net/unicode/index.html" rel="nofollow">www.alanwood.net/unicode/index.html</a> there's a useful resource for checking what your own browser can and can't display, given the fonts installed on your system.) Another issue is that many of the glyphs that wind up being displayed when you rely on Unicode support are improperly sized or positioned or are just plain ugly—at least for those brought up with TeX sensibilities. Certainly it's better to have <em>some</em> rendition of the character rather than none, but mathematics has enough of a pubic-relations problem without looking hideous too. It seems to me that downloadable fonts would offer a more reliable and consistent solution. We'll see.

Unicode has all the math symbols. Why can’t you use these for math presentation?

The Unicode standard offers code points for a very rich assortment of mathematical characters. It’s a big step in the right direction. But just because someone has installed “Unicode fonts” on a machine doesn’t mean there are glyphs available for all those code points. (At http://www.alanwood.net/unicode/index.html there’s a useful resource for checking what your own browser can and can’t display, given the fonts installed on your system.)

Another issue is that many of the glyphs that wind up being displayed when you rely on Unicode support are improperly sized or positioned or are just plain ugly—at least for those brought up with TeX sensibilities. Certainly it’s better to have some rendition of the character rather than none, but mathematics has enough of a pubic-relations problem without looking hideous too.

It seems to me that downloadable fonts would offer a more reliable and consistent solution. We’ll see.

]]> By: Aleks Totic http://bit-player.org/2009/math-fonts-and-html#comment-1956 Aleks Totic Wed, 18 Feb 2009 16:52:07 +0000 http://bit-player.org/?p=280#comment-1956 Downloadable fonts idea has been around since the birth of the web. Netscape 4 hacked it in '98: http://bit.ly/n4NBO. Getting standards in place took a lot longer, and major browsers have just started implementing it: https://developer.mozilla.org/en/CSS/@font-face Fonts are a lot tougher to get right than images/sound/video web pages need. Unicode has all the math symbols. Why can't you use these for math presentation? Downloadable fonts idea has been around since the birth of the web. Netscape 4 hacked it in ‘98: http://bit.ly/n4NBO. Getting standards in place took a lot longer, and major browsers have just started implementing it:
https://developer.mozilla.org/en/CSS/@font-face

Fonts are a lot tougher to get right than images/sound/video web pages need.

Unicode has all the math symbols. Why can’t you use these for math presentation?

]]> By: Jim Ward http://bit-player.org/2009/math-fonts-and-html#comment-1955 Jim Ward Wed, 18 Feb 2009 11:54:54 +0000 http://bit-player.org/?p=280#comment-1955 Maybe Knuth took the wrong path, instead of turning mathematicians into typesetters, it might be easier to tun typesetters into mathematicians? Maybe Knuth took the wrong path, instead of turning mathematicians into typesetters, it might be easier to tun typesetters into mathematicians?

]]> By: brian http://bit-player.org/2009/math-fonts-and-html#comment-1951 brian Tue, 17 Feb 2009 00:20:37 +0000 http://bit-player.org/?p=280#comment-1951 If the nub of the problem is worry over copyrights, then I want to know how type foundries got so much clout. Owners of copyrights on other kinds of content—words and pictures, music, movies—also fret about the misappropriation of their property, but they haven't succeeded in getting the makers of web browsers to exclude text and images and other media from the online world. As for PDFs, the ability to embed fonts in PDF documents has been one of the major reasons for the success of the format. It's what puts the 'portable' in Portable Document Format. And I can't help noting that PDF is the creation of a major font vendor. Adobe evidently considered it to be in their interest to let (some) fonts be embedded in PDF documents. <blockquote>Very few font vendors allow embedding of fonts in PDF without restrictions.</blockquote> Is that true? I'm not being snide in asking that question. It's just that I make a lot of PDFs, and I do it with software that's supposed to observe all the legal niceties, refusing to embed fonts that don't have the appropriate permission bits set. I can't recall ever getting an error notice about naughty font transgressions. Maybe I just have a lowest-common-denominator taste in fonts. (In mathematics there's no doubt that the most important faces are freely available—the Computer Modern faces from TeX and the STIX fonts.) Anyway, whatever the legal status of the issue, embedded fonts are coming soon to a browser near you. Safari already does @font-face. Firefox 3.1 will do it too, and so will a future version of Opera. If the nub of the problem is worry over copyrights, then I want to know how type foundries got so much clout. Owners of copyrights on other kinds of content—words and pictures, music, movies—also fret about the misappropriation of their property, but they haven’t succeeded in getting the makers of web browsers to exclude text and images and other media from the online world.

As for PDFs, the ability to embed fonts in PDF documents has been one of the major reasons for the success of the format. It’s what puts the ‘portable’ in Portable Document Format. And I can’t help noting that PDF is the creation of a major font vendor. Adobe evidently considered it to be in their interest to let (some) fonts be embedded in PDF documents.

Very few font vendors allow embedding of fonts in PDF without restrictions.

Is that true? I’m not being snide in asking that question. It’s just that I make a lot of PDFs, and I do it with software that’s supposed to observe all the legal niceties, refusing to embed fonts that don’t have the appropriate permission bits set. I can’t recall ever getting an error notice about naughty font transgressions. Maybe I just have a lowest-common-denominator taste in fonts. (In mathematics there’s no doubt that the most important faces are freely available—the Computer Modern faces from TeX and the STIX fonts.)

Anyway, whatever the legal status of the issue, embedded fonts are coming soon to a browser near you. Safari already does @font-face. Firefox 3.1 will do it too, and so will a future version of Opera.

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