$rands » History » Version 3
  Per Amundsen, 07/07/2023 11:13 PM 
  
| 1 | 1 | Per Amundsen | _Added in 3.3_ | 
|---|---|---|---|
| 2 | |||
| 3 | *$rands(v1,v2)* | ||
| 4 | |||
| 5 | Returns a random number or letter between v1 and v2 using encryption and high entropy. | ||
| 6 | |||
| 7 | _See also [[$rand]], [[$r]]._ | ||
| 8 | |||
| 9 | *Parameters* | ||
| 10 | |||
| 11 | 2 | Per Amundsen | table(ktable). | 
| 12 | |*Parameter*|*Description*| | ||
| 13 | 3 | Per Amundsen | | v1 | Start number or letter [0-9A-Za-z]. | | 
| 14 | | v2 | End number or letter [0-9A-Za-z]. | | ||
| 15 | |||
| 16 | 1 | Per Amundsen | if v1 and v2 are both numeric, returns random number in that range | 
| 17 | otherwise returns a character in the range of characters v1 and v2 | ||
| 18 | |||
| 19 | valid number range -2^63 through 2^63-1 | ||
| 20 | |||
| 21 | *Example* | ||
| 22 | |||
| 23 | <pre> | ||
| 24 | ; Get a random number between 10 and 100. | ||
| 25 | //echo -ag $rands(10,100) | ||
| 26 | |||
| 27 | ; Get a random number between -10 and +10. | ||
| 28 | //echo -ag $rands(10,-10) | ||
| 29 | |||
| 30 | ; Get a random letter between g and y. | ||
| 31 | //echo -ag $rands(g,y) | ||
| 32 | |||
| 33 | ; Get a random character between A and z. Since 'A' is codepoint 65 and 'z' is codepoint 122, this includes non-alphanumeric codepoints 91-96 [\]^_` | ||
| 34 | //echo -ag $rands(A,z) | ||
| 35 | |||
| 36 | To obtain only the 52 case-insensitive characters: //echo -a $iif($rands(0,1),$rands(A,Z),$rands(a,z)) | ||
| 37 | |||
| 38 | Numeric includes numbers at the beginning of strings. | ||
| 39 | //echo -a $rands(1X,4X) is the same as $rands(1,4) | ||
| 40 | |||
| 41 | Only 1st character of non-numeric string is used. | ||
| 42 | //echo -a $rands(AB,CD) is in the range A through C | ||
| 43 | |||
| 44 | No 'good' random number generator creates equal outcome of all numbers in the range, but they should be fairly close to the average | ||
| 45 | //hfree -w test | hmake test | var %i 100000 | while (%i) { hinc test $rands(1,100)) | dec %i } | var %i 1 , %a | while (%i isnum 1-100) { var %a %a %i $+ = $+ $hget(test,%i) | inc %i } | echo -a %a | ||
| 46 | </pre> |