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NumericFunction

NumericFunction
is an attribute that can be assigned to a symbol f to indicate that should be considered a numeric quantity whenever all the are numeric quantities.
  • Most standard built-in mathematical functions have the attribute NumericFunction.
  • If you assign the attribute NumericFunction to a function that does not yield numerical values, then NumericQ will give misleading results.
Exp has the NumericFunction attribute:
When Exp has an argument that is a number, constant, or numeric, the result is numeric:
In most cases when NumericQ[expr] gives True, then N[expr] yields an explicit number:
Exp has the NumericFunction attribute:
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When Exp has an argument that is a number, constant, or numeric, the result is numeric:
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In most cases when NumericQ[expr] gives True, then N[expr] yields an explicit number:
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Out[3]=
Define to be a numeric function:
If you have not assigned to yield numerical values, then NumericQ gives misleading results:
Assign to evaluate for arguments that are approximate numbers:
The system symbols that are numeric functions:
Define a function that can represent an exact value:
Assign N to give the derivative with respect to a of the solution of an ODE at :
Assign f for approximate numbers:
f[1] does not evaluate but represents a number:
It will work with any precision (within reasonable limits!):
A plot of the function:
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