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Random Subset

Creates random combinations from a given set. Enter something like numbers or names (10,000 characters are the maximum), that are separated by a certain character (e.g. a comma or a space). Then determine, how many output values you want to have. The default value here is 2. The default separator is a comma, but a space is often more suitable. Two or more separators should not be placed in a row.

Creation of combinations by a random generator.

An example: the input set is 1,2,3,4,5,6,7,8,9 .The separator is a comma, and five random values are to be determined from this set. The output set can then be 6,7,8,3,4. The number of input values here is, of course, 9.
For those interested: 9*8*7*6*5 different permutations are possible here, i.e., 15120. The general formula for a subset with k elements from a set with n elements is n!/(n-k)!. If the order is not important, then the formula is n!/[k!*(n-k)!]; in this example, there would still be 126 possibilities, which are called combinations.

The field before output values specifies how many elements the output set should contain. If this value is greater than or equal to the number of elements, then all elements will be output in random order. In this case, this calculator performs roughly the same function as the one for random sorting, although the latter uses only spaces and line breaks as separators.
Subset is a term from set theory. A subset contains only elements from the original set, which is called superset. If it is a proper subset, then it contains fewer elements than the superset has. In set theory, the order of the elements of a set is irrelevant, and duplicate elements are considered as one. The values displayed here in the random subset have also a random order. If elements occur multiple times in the input set, they can also occur multiple times in the output set. If you want to remove duplicate elements, you can clean up the set beforehand on the Set Theory page. There you can also perform other simple operations from set theory that are not random-based.