I render dynamically the following code using MathJax:
When $a \ne 0$, there are two solutions to \(ax^2 + bx + c = 0\) and they are
$$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$
In equation \eqref{eq:sample}, we find the value of an interesting integral:
\begin{equation}
\int_0^\infty \frac{x^3}{e^x-1}\,dx = \frac{\pi^4}{15}
\label{eq:sample}
\end{equation}
using Hub.Queue
MathJax.Hub.Queue(["Typeset",MathJax.Hub]);
The first time the rendering works well. But when I try to render again using the same code only the first part is rendered, but the second part (which starts from \begin) does not parsed and shown in the black frame. Why it happens?
The problem is the use of \label. When the math is re-typeset, the label already exists (from the first typesetting), and so the TeX input jax reports that as an error (disable the noErrors extension to see the error message).
You need to reset the labels (and presumably the equation numbers) before you typeset again. To do that, use
MathJax.Hub.Queue(
["resetEquationNumbers",MathJax.InputJax.TeX],
["Typeset",MathJax.Hub]
);
instead of the MathJax.Hub.Queue(["Typeset",MathJax.Hub]) call.
I am trying to render MathML equations on svg using d3.js. Can anyone help me getting a quadratic equation on svg. I tried doing it using foreign object with no success.
I spent quite some time trying to make it work in a JSFiddle with no success, but it works great on my PC. JSFiddle here. Do you mind trying the following and let me know if it works with you too?
Step 1. Load MathJax
<script type="text/javascript" src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
Step 2. Use this code to append a foreignObject
var svg = d3.select("body").append("svg").attr("width",400).attr("height",400)
var text = svg.append("foreignObject").attr("width",100).attr("height",100)
text.text("$$ x = \\sum_{i \\in A} i^{2} $$")
MathJax.Hub.Queue(["Typeset",MathJax.Hub]);
However, if you still prefer MathML, then you can use the following:
text.html("<math display=\"block\"><mrow><mi>x</mi><mo>=</mo><mfrac><mrow><mo>−</mo><mi>b</mi><mo>±</mo><msqrt><mrow><msup><mi>b</mi><mn>2</mn></msup><mo>−</mo><mn>4</mn><mi>a</mi><mi>c</mi></mrow></msqrt></mrow><mrow><mn>2</mn><mi>a</mi></mrow></mfrac></mrow></math>")
I know I am adding more scripts for you to load, but my understanding is that MathML is not really much used any more.
I hope it helps.
EDIT
Finally a JSFiddle here: link
Thanks
You've two bugs
foreignObject must have width/height attributes
mathml elements must be created in the mathml namespace
Fixing these results in this...
d3.ns.prefix.mathml = "http://www.w3.org/1998/Math/MathML";
var foreignObject = d3.select("body")
.append("svg")
var x = foreignObject.append("foreignObject")
.attr("requiredExtensions", "http://www.w3.org/1999/xhtml")
.attr("width", "100")
.attr("height", "100")
var text = x.append("mathml:mo")
var row = x.append("mathml:mrow")
row.append("mathml:mi").text("a")
row.append("mathml:mo").text('\u2062')
var msup = row.append("msup")
msup.append("mathml:mi").text("x")
msup.append("mathml:mi").text("2")
row.append("mathml:mo").text("+")
row.append("mathml:mi").text("b")
row.append("mathml:mo").text('\u2062')
row.append("mathml:mi").text('x')
row.append("mathml:mo").text('+')
row.append("mathml:mi").text('c')
or as a fiddle
I'm trying to sync up my image slides with their textblocks. I've found that Cycle 2 is a great jQuery plug-in and a simple code got me quite far. There's one issue, however. Whenever the text slides for the first time the transition is really bad. The letters of the current and next block "morph" into eachother for a second. After the first cycle everything works as it should.
Here's the cycle code:
$("#slideshow").cycle({
timeout:0, // no autoplay
fx: 'scrollHorz',
randomizeEffects: false,
next: '#next',
prev: '#prev',
});
$("#text").cycle({
timeout:0, // no autoplay
fx: 'scrollHorz',
next: '#next',
prev: '#prev',
});
U can see everything in this fiddle: http://jsfiddle.net/lucb792/85TCZ/1/ (just click arrow left or right)
Is this something that can be fixed, or do I need to search for other solutions to make something like this?
It looks like the plugin is changing the width of the text the first time you use the prev/next controls. Instead of setting the width to the #text, set the width to the divs inside #text slideshow. Changing the CSS to this fixed it for me:
#text div{
width:600px;
}
Here is the fiddle: http://jsfiddle.net/bbernar1/85TCZ/3/
I am using d3.js to build a little project that involves data, shapes and text. According to the data, the text appears inside of a shape. If you mouse-over the shape, the shape should become larger and show more text.
The text is added in the following manner and it works fine:
Shapes
.append("foreignObject")
[...]
.append("xhtml:body")
.style("font", "14px 'Helvetica Neue'")
.html(function(d) {return d.text; });
I use foreignObject rather than text because I need the text to line-wrap and this is the only way that I've so far been able to achieve this effect.
What's giving me grief is the mouse-over. I can re-size the shape just fine but I am having trouble calling a transition on the text. In fact, I don't really know how to access it successfully.
Here is some of the code from the mouse-over event:
d3.select(this)
.transition()
.duration(250)
.attr("height", function(d,i) {
d.showAll()
//d.textObject.width = 4;
return d.height;
} );
d3.select(this).select("foreignObject").transition()
.duration(250)
.select("xhtml:body")
.html(function(d) {return d.text; });
The idea is that the showAll() function has already changed the text to a new value, however the code does not get that far. The message that Chrome gives me is "Uncaught TypeError: Object [object Array] has no method 'html' ".
So, how do I access the text and update it so that my transition will lead to the new text being visible and the old text disappearing?
I've been banging my head against this for a while so any help is deeply appreciated.
Replace d3.select(this).select("foreignObject") with d3.selectAll(this.getElementsByTagName("foreignObject"))
I just solved this myself and thought I would help.
For fun I am trying to see how far I can get at implementing an SVG browser client for a RIA I'm messing around with in my spare time.
But have hit what appears to be a HUGE stumbling block. There is no word wrap!!
Does anyone know of any work around (I'm thinking some kind of JavaScript or special tag I don't know)?
If not I'm either going to have to go the xhtml route and start sticking HTML elements in my SVG (ouch), or just come back again in ten years when SVG 1.2 is ready.
This SVG stuff is baffling, isn't it ?
Thankfully, you can achieve some good results, but it takes more work than using the HTML 5 .
Here's a screenshot of my ASP.Net / SVG app, featuring a bit of "faked" word wrapping.
The following function will create an SVG text element for you, broken into tspan pieces, where each line is no longer than 20 characters in length.
<text x="600" y="400" font-size="12" fill="#FFFFFF" text-anchor="middle">
<tspan x="600" y="400">Here a realy long </tspan>
<tspan x="600" y="416">title which needs </tspan>
<tspan x="600" y="432">wrapping </tspan>
</text>
It's not perfect, but it's simple, fast, and the users will never know the difference.
My createSVGtext() JavaScript function takes three parameters: an x-position, y-position and the text to be displayed. The font, maximum-chars-per-line and text color are all hardcoded in my function, but this can be easily changed.
To display the right-hand label shown in the screenshot above, you would call the function using:
var svgText = createSVGtext("Here a realy long title which needs wrapping", 600, 400);
$('svg').append(svgText);
And here's the JavaScript function:
function createSVGtext(caption, x, y) {
// This function attempts to create a new svg "text" element, chopping
// it up into "tspan" pieces, if the caption is too long
//
var svgText = document.createElementNS('http://www.w3.org/2000/svg', 'text');
svgText.setAttributeNS(null, 'x', x);
svgText.setAttributeNS(null, 'y', y);
svgText.setAttributeNS(null, 'font-size', 12);
svgText.setAttributeNS(null, 'fill', '#FFFFFF'); // White text
svgText.setAttributeNS(null, 'text-anchor', 'middle'); // Center the text
// The following two variables should really be passed as parameters
var MAXIMUM_CHARS_PER_LINE = 20;
var LINE_HEIGHT = 16;
var words = caption.split(" ");
var line = "";
for (var n = 0; n < words.length; n++) {
var testLine = line + words[n] + " ";
if (testLine.length > MAXIMUM_CHARS_PER_LINE)
{
// Add a new <tspan> element
var svgTSpan = document.createElementNS('http://www.w3.org/2000/svg', 'tspan');
svgTSpan.setAttributeNS(null, 'x', x);
svgTSpan.setAttributeNS(null, 'y', y);
var tSpanTextNode = document.createTextNode(line);
svgTSpan.appendChild(tSpanTextNode);
svgText.appendChild(svgTSpan);
line = words[n] + " ";
y += LINE_HEIGHT;
}
else {
line = testLine;
}
}
var svgTSpan = document.createElementNS('http://www.w3.org/2000/svg', 'tspan');
svgTSpan.setAttributeNS(null, 'x', x);
svgTSpan.setAttributeNS(null, 'y', y);
var tSpanTextNode = document.createTextNode(line);
svgTSpan.appendChild(tSpanTextNode);
svgText.appendChild(svgTSpan);
return svgText;
}
The logic for word-wrapping is based on this HTML5 Canvas tutorial
I hope you find this useful !
Mike
http://www.MikesKnowledgeBase.com
UPDATE
One thing I forgot to mention.
That "Workflow diagram" screen that I've shown above was originally just written using an HTML 5 canvas. It worked beautifully, the icons could be dragged, popup menus could appear when you clicked on them, and even IE8 seemed happy with it.
But I found that if the diagram became "too big" (eg 4000 x 4000 pixels), then the would fail to initialise in all browsers, nothing would appear - but - as far as the JavaScript code was concerned, everything was working fine.
So, even with error-checking, my diagram was appearing blank, and I was unable to detect when this showstopper problem was occurring.
var canvasSupported = !!c.getContext;
if (!canvasSupported) {
// The user's browser doesn't support HTML 5 <Canvas> controls.
prompt("Workflow", "Your browser doesn't support drawing on HTML 5 canvases.");
return;
}
var context = c.getContext("2d");
if (context == null) {
// The user's browser doesn't support HTML 5 <Canvas> controls.
prompt("Workflow", "The canvas isn't drawable.");
return;
}
// With larger diagrams, the error-checking above failed to notice that
// the canvas wasn't being drawn.
So, this is why I've had to rewrite the JavaScript code to use SVG instead. It just seems to cope better with larger diagrams.
There is also foreignObject tag. Then you can embed HTML in SVG which gives the greatest flexibility. HTML is great for document layout and has been hacked to no end to support application layout, drawing, and everything us developers want. But it's strength is word wrapping and document layout. Let HTML do what it does best, and let SVG do what it does best.
http://www.w3.org/TR/SVG/extend.html
This works for most browsers FireFox, Opera, Webkit, except IE (as of IE11). :-( Story of the web ain't it?
SVGT 1.2 introduces the textArea element http://www.w3.org/TR/SVGTiny12/text.html#TextInAnArea , but it is only experimentally supported by Opera 10 at the moment. I don't know if other browsers will ever plan on implementing it, though I hope they will.
Per this document, it appears that tspan can give the illusion of word wrap:
The tspan tag is identical to the text tag but can be nested inside text tags and inside itself. Coupled with the 'dy' attribute this allows the illusion of word wrap in SVG 1.1. Note that 'dy' is relative to the last glyph (character) drawn.
The svg.js library has a svg.textflow.js plugin. It's not ultra fast but it does the trick. It even stores overflowing text in a data attribute so you can use it to create continuously flowing columns. Here the text flow example page.
An alternative method is to use Andreas Neuman's text box object.
These days, flowPara can do word wrapping, but I have yet to find a browser that supports it properly.
I've been looking for a solution about word wrapping in svg so many hours (or many days).
If you can in your app, edit your code to put some tspan, or any other method, go in it.
Text wrapping will be implement in the 1.2 version but except opera, no browser fully implement it yet (4 years, the specification are on the W3 ...).
Because I had to use some alignment settings, i couldn't use any of the code that many forum can provide (no foreign object, no carto script or anything).
If I post this message, it's just in order to be usefull to some other people when googling word wrapping svg because this post on the top result and in many case, this post doesn't help.
Here is a cool, easy and light solution :
http://dev.w3.org/SVG/profiles/1.1F2/test/svg/text-dom-01-f.svg