Switch

Switch[expr,form1,value1,form2,value2,]

evaluates expr, then compares it with each of the formi in turn, evaluating and returning the valuei corresponding to the first match found.

Details

  • Only the valuei corresponding to the first formi that matches expr is evaluated. Each formi is evaluated only when the match is tried.
  • If the last formi is the pattern _, then the corresponding valuei is always returned if this case is reached.
  • If none of the formi match expr, the Switch is returned unevaluated.
  • Switch has attribute HoldRest.
  • You can use Break, Return, and Throw in Switch.

Examples

Basic Examples  (2)

Process Boolean value to 1 or 0, giving a message and defaulting to 0 when not Boolean:

Give a suggested symbolic transformation for an expression:

Try the transformation:

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

Text

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

CMS

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

APA

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

BibTeX

@misc{reference.wolfram_2021_switch, author="Wolfram Research", title="{Switch}", year="1988", howpublished="\url{https://reference.wolfram.com/language/ref/Switch.html}", note=[Accessed: 17-January-2022 ]}

BibLaTeX

@online{reference.wolfram_2021_switch, organization={Wolfram Research}, title={Switch}, year={1988}, url={https://reference.wolfram.com/language/ref/Switch.html}, note=[Accessed: 17-January-2022 ]}