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