NHoldFirst

NHoldFirst

is an attribute which specifies that the first argument to a function should not be affected by N.

Examples

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Basic Examples  (1)

Prevent N from affecting the first argument of a function:

Scope  (2)

System symbols with the NHoldFirst attribute:

The ^(th) zero of the zeta function on the critical line with the imaginary part greater than :

N does not affect the index :

When the second argument is numeric, N evaluates numerically:

Applications  (1)

Define an "inverse" for :

Set the NHoldFirst attribute so that remains an integer:

A symbolic representation of an inverse of :

This remains unmodified with N:

With a numeric value of x, the function binv evaluates numerically:

Properties & Relations  (1)

HoldFirst prevents evaluation while NHoldFirst only prevents numerical evaluation:

You can prevent both by setting both attributes:

Wolfram Research (1996), NHoldFirst, Wolfram Language function, https://reference.wolfram.com/language/ref/NHoldFirst.html.

Text

Wolfram Research (1996), NHoldFirst, Wolfram Language function, https://reference.wolfram.com/language/ref/NHoldFirst.html.

CMS

Wolfram Language. 1996. "NHoldFirst." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/NHoldFirst.html.

APA

Wolfram Language. (1996). NHoldFirst. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/NHoldFirst.html

BibTeX

@misc{reference.wolfram_2025_nholdfirst, author="Wolfram Research", title="{NHoldFirst}", year="1996", howpublished="\url{https://reference.wolfram.com/language/ref/NHoldFirst.html}", note=[Accessed: 18-April-2025 ]}

BibLaTeX

@online{reference.wolfram_2025_nholdfirst, organization={Wolfram Research}, title={NHoldFirst}, year={1996}, url={https://reference.wolfram.com/language/ref/NHoldFirst.html}, note=[Accessed: 18-April-2025 ]}