6430fcda6f
I don't exactly know the use of this snippet but contributors can recommend on this approach of `.reduce()`.
19 lines
622 B
Markdown
19 lines
622 B
Markdown
### Square The Data
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Pass an array of integers you want to sqaure it
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Here using `.reduce()` the new object is accumulator and one by one values from array are passed and go through function.
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```
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const arr = [1,2,3,4,5,6,7];
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arr.reduce(function(a,b){
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a[b] = b * b;
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return a;
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},{}) // {1: 1, 2: 4, 3: 9, 4: 16, 5: 25, 6: 36, 7: 49}
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//
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callback accumulator currentValue currentIndex array return value
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first call 1 1 0 [0, 1, 2, 3, 4] 1
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second call 2 2 1 [0, 1, 2, 3, 4] 4
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third call 3 3 2 [0, 1, 2, 3, 4] 9
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...
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```
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