## ? Deal

Two-argument form See also one-argument form Roll

Generates as many random numbers as are specified in the left-hand argument from the first N numbers starting at ŚIO, where N is specified in the right-hand argument. Each number generated is unique; that is to say there are no repetitions. The left and right arguments must be simple numeric scalars or one-element vectors.

                 10 ? 100                (A request for 10 unique random numbers
           46 54 22 5 68 94 39 52 84 4    in the range 1 to 100, assuming ŚIO is 1 )
                 LIST „ 3 ? 10           (3 random numbers between 1 and 10
                                          are put in LIST)
                 BINGO„4 4˝16?100
                 BINGO                   (16 random numbers between 1 and 100
           41 12 46 71                    are put into a 4-by-4 matrix called
            6 54 68  4                    BINGO)
           63 94 87 58
           21 70 50 75
                 4 ? 3                   (A request for 4 unique integers in
           DOMAIN ERROR                   the range 1 to 3 causes an error)

Note: The system variable ŚRL (random link) contains a value used to generate random numbers. To generate the same number(s) on two occasions, set ŚRL to the same value before each use of ?.

                 ŚRL „ 12345
                 5 ? 10000
           97 834 948 36 12
                 ŚRL „ 12345
                 5 ? 10000
           97 834 948 36 12

Topic: APLX Help : Help on APL language : APL Primitives : ? Deal

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