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Explore Stack Internal Anonymous tacit prefix function. Assumes ⎕IO (Index Origin) to be 0, which is default on many systems. 10-indexed.
+/⊢↑∘∊¯1,¨⍨⍳ +/ the sum of
⊢↑ the first n elements
∘∊ of the ϵnlisted (flattened)
¯1,¨⍨ negative-one-appended-to-each
⍳ first n ɩndices (0 through n–1
Anonymous tacit prefix function. Assumes ⎕IO (Index Origin) to be 0, which is default on many systems. 1-indexed.
+/⊢↑∘∊¯1,¨⍨⍳ +/ the sum of
⊢↑ the first n elements
∘∊ of the ϵnlisted (flattened)
¯1,¨⍨ negative-one-appended-to-each
⍳ first n ɩndices (0 through n–1
Anonymous tacit prefix function. 0-indexed.
+/⊢↑∘∊¯1,¨⍨⍳ +/ the sum of
⊢↑ the first n elements
∘∊ of the ϵnlisted (flattened)
¯1,¨⍨ negative-one-appended-to-each
⍳ first n ɩndices (0 through n–1
Anonymous tacit prefix function. Assumes ⎕IO (Index Origin) to be 0, which is default on many systems. 1-indexed.
+/⊢↑∘∊¯1,¨⍨⍳ Try it online!Try it online!
+/ the sum of
⊢↑ the first n elements
∘∊ of the ϵnlisted (flattened)
¯1,¨⍨ negative-one-appended-to-each
⍳ first n ɩndices (0 through n–1
Anonymous tacit prefix function. Assumes ⎕IO (Index Origin) to be 0, which is default on many systems. 1-indexed.
+/⊢↑∘∊¯1,¨⍨⍳ Try it online!
+/ the sum of
⊢↑ the first n elements
∘∊ of the ϵnlisted (flattened)
¯1,¨⍨ negative-one-appended-to-each
⍳ first n ɩndices (0 through n–1
Anonymous tacit prefix function. Assumes ⎕IO (Index Origin) to be 0, which is default on many systems. 1-indexed.
+/⊢↑∘∊¯1,¨⍨⍳ +/ the sum of
⊢↑ the first n elements
∘∊ of the ϵnlisted (flattened)
¯1,¨⍨ negative-one-appended-to-each
⍳ first n ɩndices (0 through n–1
Anonymous tacit prefix lambdafunction. Assumes ⎕IO (Index Origin) to be 0, which is default on many systems. 1-indexed n'th.
{⍵⊃+\0,∊¯1+/⊢↑∘∊¯1,¨⍨⍳⍵}¨⍨⍳ Try it online! Try it online!
{…}+/ dfn; ⍵ is the argument, e.g. 4:the sum of
⍳⍵⊢↑ ɩndices (0 through argument–1);the first [0,1,2,3]
¯1,⍨¨ append –1 to each; [[0,-1],[1,-1],[2,-1],[3,-1]]n elements
∊∘∊ of the ϵnlistnlisted (flattenflattened); [0,-1,1,-1,2,-1,3,-1]
0¯1,¨⍨ prepend a zero; [0,0,-1,1,-1,2,-1,3,-1]negative-one-appended-to-each
+\⍳ cumulative sum;first [1,0,2,1,4,3,7,6]
⍵⊃n pick the argument'th; ɩndices (0 through 1n–1
Anonymous prefix lambda. Assumes ⎕IO (Index Origin) to be 0, which is default on many systems. 1-indexed n'th.
{⍵⊃+\0,∊¯1,¨⍨⍳⍵} {…} dfn; ⍵ is the argument, e.g. 4:
⍳⍵ ɩndices (0 through argument–1); [0,1,2,3]
¯1,⍨¨ append –1 to each; [[0,-1],[1,-1],[2,-1],[3,-1]]
∊ ϵnlist (flatten); [0,-1,1,-1,2,-1,3,-1]
0, prepend a zero; [0,0,-1,1,-1,2,-1,3,-1]
+\ cumulative sum; [1,0,2,1,4,3,7,6]
⍵⊃ pick the argument'th; 1
Anonymous tacit prefix function. Assumes ⎕IO (Index Origin) to be 0, which is default on many systems. 1-indexed.
+/⊢↑∘∊¯1,¨⍨⍳ Try it online!
+/ the sum of
⊢↑ the first n elements
∘∊ of the ϵnlisted (flattened)
¯1,¨⍨ negative-one-appended-to-each
⍳ first n ɩndices (0 through n–1