There are nine reasons why the evaluate function cannot be used: incorrect syntax, not importing the evaluate module, undefined symbols, expressions containing unsupported functions or operations, invalid expressions, type mismatches, and symbol resolution failures. , unknown symbol value and old version. Check and resolve these causes to resolve problems you encounter with the evaluate function.
Why the evaluate function cannot be used
Reason 1: Wrong syntax
evaluate(expression)
Cause 2: The evaluate module is not imported
from sympy import evaluate
Cause three: The symbol is undefined
symbols()
function to define symbols and then assign them to expressions. Cause four: The expression contains an unsupported function or operation
Cause five: Invalid expression
Cause six: Type mismatch
Cause seven: Symbol parsing failed
simplify()
or expand()
function to preprocess expressions to simplify calculations. Cause eight: The symbol value is unknown
solve()
function to solve for values. Cause 9: The version is too old
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