| Exercise 15 | Index << >> |
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Let x and y be vectors of floating point numbers. Compare the times for x⍳y and x{⎕ct←0 ⋄ ⍺⍳⍵}y . Compare their results.
I0←{⎕ct←0 ⋄ ⍺⍳⍵}
x ← ?1e6⍴0
y ← ?1e6⍴0
cmpx 'x⍳y' 'x I0 y'
x⍳y → 2.05e¯1 | 0% ⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕
x I0 y → 1.22e¯1 | -41% ⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕
x ← 0.1 , ?1e6⍴9e5
y ← 100 × 100 ÷⍨ x
cmpx 'x⍳y' 'x{⎕ct←0 ⋄ ⍺⍳⍵}y'
x⍳y → 1.79e¯1 | 0% ⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕
* x I0 y → 1.11e¯1 | -39% ⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕
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