Name Meaning MathML
true Boolean value true <true/>
false Boolean value false <false/>
pi Mathematical constant pi <pi/>
avogadro Value of Avogadro's constant stipulated by SBML <csymbol encoding="text" definitionURL="http://www.sbml.org/sbml/symbols/avogadro"> avogadro </csymbol/>
time Simulation time as defined in SBML <csymbol encoding="text" definitionURL="http://www.sbml.org/sbml/symbols/time"> time </csymbol/>
inf, infinity Mathematical constant "infinity" <infinity/>
nan, notanumber Mathematical concept "not a number" <notanumber/>
Mathematical symbols defined in the "Level 3" text-string formula syntax.