CountDistinct
CountDistinct[list]
gives the number of distinct elements that appear in list.
Examples
open allclose allProperties & Relations (1)
CountDistinct[list] is equivalent to Length[DeleteDuplicates[list]]:
Wolfram Research (2014), CountDistinct, Wolfram Language function, https://reference.wolfram.com/language/ref/CountDistinct.html.
Text
Wolfram Research (2014), CountDistinct, Wolfram Language function, https://reference.wolfram.com/language/ref/CountDistinct.html.
CMS
Wolfram Language. 2014. "CountDistinct." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/CountDistinct.html.
APA
Wolfram Language. (2014). CountDistinct. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/CountDistinct.html