Mega Code Archive

 
Categories / Delphi / Variables
 

Randseed - reposition the random number generator next value

var RandSeed : LongInt; Description The RandSeed variable is used in conjunction with the Random function. It changes the seed used that Delphi uses to generate its range of 232 pseudo random numbers. Related commands Random Generate a random floating point or integer number Randomize Reposition the Random number generator next value RandomRange Generate a random integer number within a supplied range Example code : Run this code twice to see the effect of RandSeed var int : Integer; i : Integer; hours, mins, secs, milliSecs : Word; begin // Get random numbers using the default random seed value ShowMessage('Fixed first 5 random numbers'); for i := 1 to 5 do begin int := 1 + Random(100); // The 100 value gives a range 0..99 ShowMessage('int = '+IntToStr(int)); end; // Now change the random seed to the milliseconds value // of the current time DecodeTime(now, hours, mins, secs, milliSecs); ShowMessage(''); ShowMessage('Setting randSeed to value : '+IntToStr(milliSecs)); ShowMessage(''); RandSeed := milliSecs; // Get an integer random number in the range 1..100 ShowMessage('Random next 5 numbers'); for i := 1 to 5 do begin int := 1 + Random(100); // The 100 value gives a range 0..99 ShowMessage('int = '+IntToStr(int)); end; end; Show full unit code Fixed first 5 random numbers int = 1 int = 4 int = 87 int = 21 int = 28 Setting random seed to value : 660 Random next 5 numbers int = 72 int = 62 int = 28 int = 63 int = 44