Pablo, On Wed, Jul 3, 2013 at 5:38 AM, peibol <[email protected]> wrote: > It will be something like that. For the moment, I'm just implemented the > basics of presentation mathml. I will add features as I need them. > > After running it, sympify should be called. What do you think about it? > > def parseMML(mmlinput): > from lxml import etree > from StringIO import * > from lxml import objectify > mmlinput= mmlinput.replace(' xmlns="', ' xmlnamespace="') > parser = etree.XMLParser(ns_clean=True,remove_pis=True,remove_comments=True) > tree = etree.parse(StringIO(mmlinput), parser) > objectify.deannotate(tree,cleanup_namespaces=True,xsi=True,xsi_nil=True) > mmlinput=etree.tostring(tree.getroot()) > exppy="" #this is the python expression > symvars=[] #these are symbolic variables which can eventually take part in > the expression > events = ("start", "end") > level = 0 > context = etree.iterparse(StringIO(mmlinput),events=events) > for action, elem in context: > if (action=='start') and (elem.tag=='mfrac'): > level += 1 > mmlaux=etree.tostring(elem[0]) > (a,b)=parseMML(mmlaux) > symvars.append(b) > exppy+=a > exppy+='/' > mmlaux=etree.tostring(elem[1]) > (a,b)=parseMML(mmlaux) > symvars.append(b) > exppy+=a > if (action=='end') and (elem.tag=='mfrac'): > level -= 1 > if level: > continue > if (action=='start') and (elem.tag=='mrow'): > exppy+='(' > if (action=='end') and (elem.tag=='mrow'): > exppy+=')' > if action=='start' and elem.tag=='mn': #this is a number > exppy+=elem.text > if action=='start' and elem.tag=='mi': #this is a variable > exppy+=elem.text > symvars.append(elem.text) #we'll return the variable, so sympy can sympify > it afterwards > if action=='start' and elem.tag=='mo': #this is a operation > exppy+=elem.text > return (exppy, symvars) > > > With the example: mmlinput='''<?xml version="1.0"?> <math > xmlns="http://www.w3.org/1998/Math/MathML"; > xmlns:mml="http://www.w3.org/1998/Math/MathML"; > xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; > xsi:schemaLocation="http://www.w3.org/1998/Math/MathML > http://www.w3.org/Math/XMLSchema/mathml2/mathml2.xsd";> <mrow> <mfrac> <mrow> > <mn>3</mn> </mrow> <mrow> <mn>57</mn> </mrow> </mfrac> </mrow> </math>''' > > We get: > exppy='((3)/(57))'
I think that's a great start. I assume you pass the expression to sympify() and obtain a SymPy expression as a result. Aaron, I think we should have this in sympy, what do you think? We can install lxml in .travis.yml and have this tested. If so, I can help you Pablo with sending a PR and get it setup. Ondrej -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy. For more options, visit https://groups.google.com/groups/opt_out.
