[sympyprinting] MathJax can't render \root{m}{n}

[miham]

When running IPython notebook (0.12 or git) with sympy profile, latex representation of higher order roots in the output cell doesn't get rendered. To reproduce the problem, run $ ipython2 notebook --profile=sympy and then execute

In [6]: a = 3**(S(1)/4) 
a

Out[6]: \root{4}{3}  # I should see nicely rendered root here, not LaTex code.

SymPy 0.7.1. is used for this examples. The problem is that sympyprinting extension uses iTex markup instead of regular Latex. Why is that good? Here's the difference in root representation:

In [7]: latex(a)
Out[7]: \sqrt[4]{3}   # MathJax can render this.

In [8]: latex(a, itex=True)
Out[8]: \root{4}{3}   # MathJax can't render this.

There are two workarounds:

• You can set itex=False in extensions.sympyprinting.print_latex(), but that will probably break something else, or
• add a line that replaces iTex form with LaTex form, import re; s = re.sub(r'\\root\{(.*?)\}\{(.*?)\}', r'\\sqrt[\1]{\2}', s)

[fperez]

See discussion on #1361 for the status of this one, at least on my machine.