# Constant

is an attribute that indicates zero derivative of a symbol with respect to all parameters.

# Details

• Constant is used by Dt.
• Functions f[] are taken to have zero total derivative if f has attribute Constant.
• Mathematical constants such as Pi have attribute Constant.

# Examples

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## Basic Examples(2)

π is a mathematical constant representing a number:

π is not explicitly a number:

π is numeric and evaluates to a number with N:

Define f to be a constant function for total derivatives computed with Dt:

## Scope(2)

The built-in system mathematical constants:

They are all NumericQ:

They all represent exact values that can be evaluated to numbers of any precision with N:

Define f locally to be a constant function:

This does not affect subsequent computations with Dt:

Using the Constants option in Dt is similar, but has completely unambiguous output:

Wolfram Research (1988), Constant, Wolfram Language function, https://reference.wolfram.com/language/ref/Constant.html.

#### Text

Wolfram Research (1988), Constant, Wolfram Language function, https://reference.wolfram.com/language/ref/Constant.html.

#### CMS

Wolfram Language. 1988. "Constant." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/Constant.html.

#### APA

Wolfram Language. (1988). Constant. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/Constant.html

#### BibTeX

@misc{reference.wolfram_2024_constant, author="Wolfram Research", title="{Constant}", year="1988", howpublished="\url{https://reference.wolfram.com/language/ref/Constant.html}", note=[Accessed: 12-July-2024 ]}

#### BibLaTeX

@online{reference.wolfram_2024_constant, organization={Wolfram Research}, title={Constant}, year={1988}, url={https://reference.wolfram.com/language/ref/Constant.html}, note=[Accessed: 12-July-2024 ]}