suhr/nk.csv

Syntax	Name	Description	Example	Output
+/x	Sum	Sum all value in x	+/1 2 3 4 5	15
-':x	Deltas	Pairwise differences in x	-':1 2 3 4	1 1 1 1
\|+x	Rotate matrix	Rotate x counterclockwise	\|+3 3#!9	(2 5 8;1 4 7;0 3 6)
x@<x	Sort	Sort x	{x@<x}@8 3 7 1	1 3 7 8
?x,y	Set union	Unique elements from x and y	?"abac","adob"	"abcdo"
x^x^y	Intersection	Common elements from x and y	{?x^x^y}["abac";"adob"]	"aba"
x\|-x	Absolute value	Absolute value of x	{x\|-x}@-1	1
*/y#x	Power	x in power of y (y>0)	{*/y#x}[2;5]	32
y@(#y)!x+!#y	Rotate left	Rotate y by x elements to the left	{y@(#y)!x+!#y}[3;"abcde"]	"deabc"
`c$x-32*~"a{"'x	Uppercase	Upper case of all alphabetic chars	{`c$x-32*~"a{"'x}@"happy"	"HAPPY"
@[x;i;:;v]	Update	Update value at x[i] with v	a:+`a`b!(0 1 ; 2 3);@[a;0;:;(3,4)]	+`a`b!(3 1;4 3)
\|/x	Max, Any	Largest element in x	\|/3 5 2	5
&/x	Min, All	Smallest element in x	&/3 5 2	2
(+/x)%#x	Average	Arithmetic mean	{(+/x)%#x}@1 2 3 4 5	3.0
z@y/(!y@<x)x	Permute axes	x⍉y⍴z	{z@y/(!y@<x)x}[2 0 1; 2 3 4; `c$"A"+!24]	"AMBNCODPEQFRGSHTIUJVKWLX"
*\|x	Last	Last element of x	*\|"abc"	"c"
*<x	Index of min	Index of smallest element in x	*<"banana"	1
*>x	Index of max	Index of largest element in x	*>"banana"	2
*/x	Product	Multiply all values in x	*/2 3 4	24
*:/x	Deep first	First value in nested array x	*:/(("ab";"cd");("ef";"gh"))	"a"
<<x	Ascending ordinals	Rank values in x by smallness	<<"baka"	2 0 3 1
<>x	Descending ordinals	Rank values in x by greatness	<>"baka"	1 2 0 3
,/x	Flatten	Remove one level of nesting	,/(("ab";"cd");("ef";"gh"))	("ab";"cd";"ef";"gh")
,//x	Enlist	Flatten nested array into a list	,//(("ab";"cd");("ef";"gh"))	"abcdefgh"
x@&y	Compress, Replicate	Repeat each value in x y times	"abcd"@&1 0 2 0	"acc"
x@\:y	Apply list	Apply each function in x to y	(2+;3*)@\:!5	(2 3 4 5 6;0 3 6 9 12)
d:#'=x; @[(1+\|/x)#0;!d;:;.d]	Where Inverse	Inverse to &	{d:#'=x; @[(1+\|/x)#0;!d;:;.d]}@ &0 2 1	0 2 1
(!1+#x)#\:x	Prefixes	Prefixes of x	{(!1+#x)#\:x}"abcde"	("";,"a";"ab";"abc";"abcd";"abcde")
(!1+#x)_\:x	Suffixes	Suffixes of x	{(!1+#x)_\:x}"abcde"	("abcde";"bcde";"cde";"de";,"e";"")
x,(-#x)_y	Shift before	Insert x into the start of y, shifting trailing elements out	{x,(-#x)_y}["foo"; "abcde"]	"fooab"
((#x)_y),x	Shift after	Insert x into the end of y, shifting leading elements out	{((#x)_y),x}["foo"; "abcde"]	"defoo"
(&#'x)@<,/.x	Group inverse	Inverse to =	{(&#'x)@<,/.x}@="banana"	"banana"
~x'y	In range	For x~(a;b) is the same as (~a>y)&y<b	~2 5'!10	0 0 1 1 1 0 0 0 0 0
z=x\|y&z	In range (inclusive)	Shorter version of (~x>z)&~z>y	{z=x\|y&z}[2;5;!10]	0 0 1 1 1 1 0 0 0 0
~^y?x	Elements of	For each element in of x check if it's in y	~^"banana"?"bar"	1 1 0
x@.=x-!#x	Consequents	Consequent sequences of x	{x@.=x-!#x}"abclmxyz"	("abc";"lm";"xyz")
m:&x; y@m@.=m-!#m	Cut by mask	Cut y by mask x	{m:&x; y@m@.=m-!#m}[0 1 1 0 1 1 1; "a42b123"]	("42";"123")