random names

• PARM varname, minlen=4, maxlen=8 # This script returns in the variable specified as "varname" a `random’# name consisting of letters and numbers - cannot start with a number. # At least "minlen" characters long and not more than "maxlen" chars. ## expression for a `random' letter: setvar letter "chr( (hpcpumsecs mod 26) + ord('A') )” ## expression for a `random' number: setvar number "chr((hpcpumsecs mod 10) + ord('0'))" ## first character must be a letter setvar !varname !letter ## now fill in the rest, must have at least "minlen" chars , up to "maxlen" setvar i 1 setvar limit min( (hpcpumsecs mod !maxlen) + !minlen, !maxlen) while setvar(i,i+1) <= limit do  if odd(hpcpumsecs) then  setvar !varname !varname + !letter  else  setvar !varname !varname + !number  endif endwhile

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• Script on jazz at: http://jazz.external.hp.com/src/scripts/randname.txt

• This example shows a script returning a value via a passed in variable.

• Shows using HPCPUMSECS to get a sort of pseudo random number.

• Breaking down the line: setvar letter "chr( (hpcpumsecs mod 26) + ord('A') )”
  • HPCPUMSECS returns some large number
  • mod 26 returns a number in the range of 0..25
  • ord(“A”) is 65 and is the decimal number of the letter “A”
  • chr(0..25 + 65) is chr(65..90), which is one of the letters A..Z

• The same logic applies to the “number” line above.

• The LIMIT line is evaluated as (using the parameter default values):
  • (hpcpumsecs mod 8) is a number in the range of 0..7
  • + minlen makes the number in the range 4..11
  • min(4..11, 8) returns a pseudo random number in the range of 4..8, which is exactly what is desired.

• The WHILE loop iterates “limit-1” times, filling in the 2nd through “limit” characters in the name. If the HPCPUMSECS value is odd at this moment we append to the name a “random” letter, else a “random” number is appended.

• It would be nice to have a pseudo random number and name generator in the CI core, IMO!