'''RANDOMIZE''' is used with a seed value to generate different random number sequences using the [[RND]] function.


{{PageSyntax}}
:: '''RANDOMIZE''' [USING] '''{''seednumber''|TIMER}'''


* The ''seed number'' can be ANY positive or negative numerical type value. The [[TIMER]] value is often used to change [[RND]] output each run.
* If the ''seed number'' is omitted, the program will display: '''Random-number seed (-32768 to 32767)?''' request on screen.
* '''USING''' resets a ''seed number'' sequence to the start of the sequence as if the program just started using that seed in '''QB64 only'''.
* '''Note:''' The RANDOMIZE USING ''seed number'' MUST be designated or a {{text|Name already in use|blue}} status error will occur! 
* If the same initial seed number is used, the sequence of random numbers returned will be identical every program run.
* The fact that random numbers would always be the same has been used for simple data encryption and decryption.
* Using a [[TIMER]] starting value ensures that the initial return sequence values are different almost every time the program is run!
* [[RUN]] should reset the [[RANDOMIZE]] sequence to the starting [[RND]] function value.(Not yet in QB64)


''Example 1:'' Using RANDOMIZE '''TIMER''' to set a different starting sequence of [[RND|random]] numbers every run.
{{CodeStart}}{{Cl|RANDOMIZE}} {{Cl|TIMER}}
{{Cl|DO...LOOP|DO}}
randnum% = INT({{Cl|RND}} * 11) + 2  'add one to multiplier as INT rounds down and never equals 10
PRINT randnum%
K$ = {{Cl|INPUT$}}(1)
{{Cl|LOOP}} {{Cl|UNTIL}} {{Cl|UCASE$}}(K$) = "Q"  'q = quit
{{Cl|END}} '' ''
{{CodeEnd}}
:''Explanation:'' Procedure generates random integer values from 2 to 12 like a pair of dice.


''Example 2:'' Repeating a random number sequence with RANDOMIZE '''USING''' and a specific seed value in '''QB64''' only.
{{CodeStart}}seed = 10
{{Cl|RANDOMIZE}} seed
Print7
{{Cl|RANDOMIZE}} seed
Print7
{{Cl|PRINT}} "Press a key to start sequence over!"
K$ = {{Cl|INPUT$}}(1) 
{{Cl|RANDOMIZE}} '''USING''' seed
Print7

{{Cl|SUB}} Print7
{{Cl|FOR...NEXT|FOR}} r = 1 TO 7
  {{Cl|PRINT}} {{Cl|RND}};
{{Cl|NEXT}}
{{Cl|PRINT}}: {{Cl|PRINT}}
{{Cl|END SUB}} '' ''
{{CodeEnd}}
: ''Explanation:'' The second RANDOMIZE statement just continues the sequence where USING in the third restarts the sequence.


''Example 3:'' Random fireworks explosions:
{{CodeStart}}{{Cl|RANDOMIZE}} {{Cl|TIMER}}
{{Cl|DEFINT}} A-Z

{{Cl|TYPE}} ftype
    vx {{Cl|AS}} {{Cl|SINGLE}}
    vy {{Cl|AS}} {{Cl|SINGLE}}
{{Cl|END}} {{Cl|TYPE}}
{{Cl|DIM}} frag(500) {{Cl|AS}} ftype 'fragments

{{Cl|DIM}} pi {{Cl|AS}} {{Cl|SINGLE}}
pi = 3.141593

{{Cl|DIM}} x {{Cl|AS}} {{Cl|SINGLE}}, y {{Cl|AS}} {{Cl|SINGLE}}
{{Cl|DIM}} t {{Cl|AS}} {{Cl|SINGLE}}, g {{Cl|AS}} {{Cl|SINGLE}}, p {{Cl|AS}} {{Cl|SINGLE}}
t = 0
g = 0.4 'gravity
p = 15 'explosion power

sw = 800
sh = 600

{{Cl|SCREEN}} {{Cl|_NEWIMAGE}}(sw, sh, 32)

DO
    {{Cl|FOR...NEXT|FOR}} i = 0 {{Cl|TO}} {{Cl|UBOUND}}(frag)
        frag(i).vx = {{Cl|RND}} * {{Cl|COS}}(2 * pi * {{Cl|RND}})
        frag(i).vy = {{Cl|RND}} * {{Cl|SIN}}(2 * pi * {{Cl|RND}})
    {{Cl|NEXT}}

    x = sw * {{Cl|RND}}
    y = sh * {{Cl|RND}}

    {{Cl|FOR...NEXT|FOR}} t = 0 {{Cl|TO}} 25 {{Cl|STEP}} 0.1
        {{Cl|LINE}} (0, 0)-(sw, sh), {{Cl|_RGB}}(0, 0, 0), BF
        {{Cl|FOR...NEXT|FOR}} i = 0 {{Cl|TO}} {{Cl|UBOUND}}(frag)
            {{Cl|PSET}} (x + t * p * frag(i).vx, y + t * p * frag(i).vy + g * t * t), {{Cl|_RGB}}(255, 255, 0)
        {{Cl|NEXT}}
        {{Cl|_DISPLAY}}
        {{Cl|_LIMIT}} 150

        {{Cl|IF...THEN|IF}} {{Cl|_KEYHIT}} = -27 {{Cl|THEN}} {{Cl|EXIT DO}}
    {{Cl|NEXT}}
{{Cl|LOOP}}
{{Cl|SYSTEM}}
{{CodeEnd}}{{small|Code by Ben}}


''See also:'' 
* [[RND]], [[INT]], [[CINT]]
* [[TIMER]]


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