We urge developers to keep in mind that the text-string formula syntax is specific to libSBML. Neither MathML nor SBML define a text-string format for mathematical formulas. LibSBML's particular syntax should not be considered to be a canonical or standard general-purpose mathematical expression syntax. LibSBML provides methods for parsing and transforming text-string math formulas back and forth from AST structures for the convenience of calling applications, but it is important to keep the system's limitations in mind.
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