If you want to do it to some reasonable extent (please see next paragraph), this is not extremely hard to do, but will be a big piece of work.
More importantly, most of advanced symbolic mathematical entities cannot be translated into an expression in any algorithmic language. One basic example is the integral. Of course, if this is, say, the integral of sin(x) dx, it can be done, but in general case this is theoretically impossible.
So, if you want to limit such transformation to a limited set of mathematical operations roughly matching the set of .NET BCL
System.Math operations and reject all other cases, you can do it. After all, MathML is expressed in XML, which represents an
expression tree (
binary expression tree ). You can use any of the XML parsing libraries to parse MathML code in a kind of DOM. From this DOM, you can generate a C# strings. The parent-child relationships between nodes will define the structure of the expression, the order and () brackets, and text nodes will represent the terminal expression nodes (such as "2" in your example), or the variable names.
Note that some MathML entities have nothing to do with mathematical expressions. One example is the concept of "row", which is related just to the graphical representation. You can effectively ignore this problem, by considering such node as a regular sub-expression. You just take in in brackets on output, without any operation (you can consider a sub-expression without operation as a "trivial" sub-expression, a unary operation which does nothing). Certainly, you may get a lot of redundant round brackets; you may decide to optimize it or not.
MathML syntax and semantics is fully described here:
W3 Math.
This is all you need.
—SA
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