52 lines
1.3 KiB
JavaScript
52 lines
1.3 KiB
JavaScript
import _curry1 from "./internal/_curry1.js";
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/**
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* Transposes the rows and columns of a 2D list.
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* When passed a list of `n` lists of length `x`,
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* returns a list of `x` lists of length `n`.
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*
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*
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* @func
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* @memberOf R
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* @since v0.19.0
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* @category List
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* @sig [[a]] -> [[a]]
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* @param {Array} list A 2D list
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* @return {Array} A 2D list
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* @example
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*
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* R.transpose([[1, 'a'], [2, 'b'], [3, 'c']]) //=> [[1, 2, 3], ['a', 'b', 'c']]
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* R.transpose([[1, 2, 3], ['a', 'b', 'c']]) //=> [[1, 'a'], [2, 'b'], [3, 'c']]
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*
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* // If some of the rows are shorter than the following rows, their elements are skipped:
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* R.transpose([[10, 11], [20], [], [30, 31, 32]]) //=> [[10, 20, 30], [11, 31], [32]]
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* @symb R.transpose([[a], [b], [c]]) = [a, b, c]
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* @symb R.transpose([[a, b], [c, d]]) = [[a, c], [b, d]]
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* @symb R.transpose([[a, b], [c]]) = [[a, c], [b]]
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*/
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var transpose =
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/*#__PURE__*/
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_curry1(function transpose(outerlist) {
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var i = 0;
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var result = [];
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while (i < outerlist.length) {
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var innerlist = outerlist[i];
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var j = 0;
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while (j < innerlist.length) {
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if (typeof result[j] === 'undefined') {
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result[j] = [];
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}
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result[j].push(innerlist[j]);
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j += 1;
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}
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i += 1;
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}
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return result;
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});
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export default transpose; |