Parses a ParseTree as a arithmetic expression
@param T arithmetic type. By default is float.
@param grammarName Name of the arithmetic grammar. Must be "ArithmeticNoVar" or "Arithmetic". By default is "ArithmeticNoVar"
@param ParseTree p ParseTree generated by ArithmeticNoVar
@return The result of the arithmetic expresion. If the ParseTree is invalid
or contains unexpected nodes, then will return NaN if T is a float or 0
if T is a integral
Parses a ParseTree as a arithmetic expression @param T arithmetic type. By default is float. @param grammarName Name of the arithmetic grammar. Must be "ArithmeticNoVar" or "Arithmetic". By default is "ArithmeticNoVar" @param ParseTree p ParseTree generated by ArithmeticNoVar @return The result of the arithmetic expresion. If the ParseTree is invalid or contains unexpected nodes, then will return NaN if T is a float or 0 if T is a integral