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DownValues [f]

gives a list of transformation rules corresponding to all downvalues (values for f[]) defined for the symbol f.

DownValues ["symbol"]

gives a list of transformation rules corresponding to all downvalues defined for the symbol named "symbol" if it exists.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Applications  
Properties & Relations  
See Also
Tech Notes
Related Guides
History
Cite this Page

DownValues [f]

gives a list of transformation rules corresponding to all downvalues (values for f[]) defined for the symbol f.

DownValues ["symbol"]

gives a list of transformation rules corresponding to all downvalues defined for the symbol named "symbol" if it exists.

Details and Options

  • You can specify the downvalues for f by making an assignment of the form DownValues [f]=list.
  • The list returned by DownValues has elements of the form HoldPattern [lhs]:>rhs.

Examples

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Basic Examples  (1)

Define values for a function f:

These are the downvalues associated with f:

Scope  (3)

DownValues returns rules corresponding to definitions made for a symbol:

Create several functions:

Obtain the downvalues of functions whose names start with f:

DownValues can be used to set the values directly:

Applications  (2)

The resulting rules are in the order given:

Now reorder the definitions:

Copy a symbol's definitions to another symbol:

Properties & Relations  (5)

Values can be defined by immediate or delayed assignments:

HoldPattern is used to protect the rules from their own definitions:

Without the HoldPattern , the left-hand side would have evaluated:

DownValues ["sym"] will issue a message if the specified symbol does not exist:

If the symbol exists but has no definitions, an empty list is returned:

Definition and Information display downvalues but do not return them as values:

DownValues returns a value that can be used in a program:

Evaluation of an expression involves applying rules for its head:

History

Introduced in 1991 (2.0) | Updated in 1996 (3.0) 2022 (13.2)

Wolfram Research (1991), DownValues, Wolfram Language function, https://reference.wolfram.com/language/ref/DownValues.html (updated 2022).

Text

Wolfram Research (1991), DownValues, Wolfram Language function, https://reference.wolfram.com/language/ref/DownValues.html (updated 2022).

CMS

Wolfram Language. 1991. "DownValues." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2022. https://reference.wolfram.com/language/ref/DownValues.html.

APA

Wolfram Language. (1991). DownValues. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/DownValues.html

BibTeX

@misc{reference.wolfram_2025_downvalues, author="Wolfram Research", title="{DownValues}", year="2022", howpublished="\url{https://reference.wolfram.com/language/ref/DownValues.html}", note=[Accessed: 16-November-2025]}

BibLaTeX

@online{reference.wolfram_2025_downvalues, organization={Wolfram Research}, title={DownValues}, year={2022}, url={https://reference.wolfram.com/language/ref/DownValues.html}, note=[Accessed: 16-November-2025]}

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