Re: ToExpression[..,TexForm] does not seem to work on

*To*: mathgroup at smc.vnet.net*Subject*: [mg104386] Re: [mg104351] ToExpression[..,TexForm] does not seem to work on*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Fri, 30 Oct 2009 02:17:06 -0500 (EST)*Reply-to*: hanlonr at cox.net

Put a space after sum in the TeX s = TeXForm[Sum[f[n], {n, 1, m}]] \sum _{n=1}^m f(n) Note the space after sum in the above output ToExpression["\\sum _{n=1}^m f(n)", TeXForm] Sum[f[n], {n, 1, m}] ToExpression["\\sum _ {n=1}^m f(n)", TeXForm] Sum[f[n], {n, 1, m}] Bob Hanlon ---- "Nasser M. Abbasi" <nma at 12000.org> wrote: ============= Version 7. Some Latex commands are converted ok to Mathematica expressions, such as: ToExpression["\\sqrt{3}", TeXForm] ToExpression["\\frac{a}{b}", TeXForm] But the next Latex "sum" command does not seem to work. Is this a known "issue" or is there a trick for one command? I take the output of the TexForm command, and then try to convert it back to Mathematica expression, but the conversion back fails: s = TeXForm[Sum[f[n], {n, 1, m}]] ToExpression[ToString[s], TeXForm] Even when I type the Latex output by hand, it does not work: ToExpression["\\sum_{n=1}^m f(n)", TeXForm] the error is : Syntax::sntxi:Incomplete expression; more input is needed. ToExpression::esntx:Could not parse \sum_{n=1}^m f(n) as Mathematica input. --Nasser