Rnd command

[Frank Brübach]

Hi Charles I dont quite understand the rnd command Like this example

If you are using sys seed all is OK If I am using another variable the result is wrong or its depending of your asm Code Part? Its confusing me a little

Code Select Expand

'-- rnd questions
'
sys hobbit
sys seed

Function Rnd(sys z1,z2) as sys
    pushad
    sys  rand
    mov  eax,z2
    sub  eax,z1
    inc  eax
    imul edx,seed,0x8088405
    inc  edx
    mov  seed,edx
    mul  edx
    add  edx,z1
    mov  rand,edx
    popad
    Return rand
End Function


function rand(sys z1,z2) as sys
mov eax,z2
sub eax,z1
inc eax
imul edx,seed,0x8088405
inc edx
mov seed,edx
mul edx
add edx,z1
return edx
end function

function brnd(sys z1,z2) as sys
seed*=0x8088405+1
eax=z2-z1+1 : mul seed
return edx+z1
end function

seed=12345 : print rnd  1,10 '4
seed=12345 : print rand 1,100 '39
seed=12345 : print brnd 1,1000 '386
'
' 2
'
hobbit=12345 : print rnd 1,10 '3

dim myvalue as integer
myvalue=2024
'myvalue=int((6*rnd)+1) 'vb
myvalue=rnd 1,6 '1
print myvalue


Perhaps you have another o2 example at Hand

Regards frank

[Charles Pegge]

Hi Frank,

From inc\chaos.inc:

rnd() returns float values between -1.0 and 1.0

irnd(min,max) returns random integers between min and max

They are only pseudo-random, of course, just scrambled numbers, dependent  on the initial seed value.

Code Select Expand

  int seed=0x12345678
  '
  function Rnd() as float
  =======================
  Static As float f, d=1/0x7fffffff
  mov eax,seed
  inc eax
  rol eax,13
  xor eax,0xdab5ca3a
  mov seed,eax
  push eax
  fild dword [esp]
  pop eax
  fmul dword d
  fstp dword f
  return f
  end function


  'ABS RANDOMISER
  '
  function arnd() as float
  ========================
  return Abs(Rnd)
  end function


  function irnd(int z1, z2) as int
  ================================
  mov    eax,z2
  sub    eax,z1
  inc    eax
  imul   edx,Seed,0x8088405
  inc    edx
  mov    Seed,edx 'store new seed
  mul    edx 'multiply eax by edx
  return edx+z1
  end Function



[Frank Brübach]

Thank you Charles

Here a little example "lottery" 6 Out of 49 in Germany Name is "Lottozahlen"..

Code Select Expand

' lottery: germany, lottozahlen 6 out of 49 plus extraball
' oxygen, by frank bruebach, 14-2-2024
'

dim i, temp as long
dim Lotto(49) as long
dim Lotterynumbers(7) AS LONG

' lotterynumber = "lottozahlen", you draw six number of 49 possibilities, 6 numbers of 49 drop down of a sphere into glasses
' extranumber = after the drawing of six number you can get the 7th number as extranumber and earn more money

  int seed=0x12345678

  function Rnd() as float
  =======================
  Static As float f, d=1/0x7fffffff
  mov eax,seed
  inc eax
  rol eax,13
  xor eax,0xdab5ca3a
  mov seed,eax
  push eax
  fild dword [esp]
  pop eax
  fmul dword d
  fstp dword f
  return f
  end function

  'ABS RANDOMISER
  '
  function arnd() as float
  ========================
  return Abs(Rnd)
  end function


  function irnd(int z1, z2) as int
  ================================
  mov    eax,z2
  sub    eax,z1
  inc    eax
  imul   edx,Seed,0x8088405
  inc    edx
  mov    Seed,edx 'store new seed
  mul    edx 'multiply eax by edx
  return edx+z1
  end Function
'
'lottery begin --------------------------- //
'
for i = 1 to 49
Lotto(i) = 1
next
i = 1
'RANDOMIZE
arnd()
do
temp = irnd(1,49)
if Lotto(temp) = 1 then
Lotterynumbers(i) = temp
Lotto(temp) = 0
i++
endif
loop until i > 7

print " Your Lottery numbers are: "
for i = 1 to 6
print ("Ball "+i+" "+str(LotteryNumbers(i)))
next
print (" And the extranumber is : " + str(LotteryNumbers(7)))
print ("end of lotterynumber short script")

PS Charles its possible to make a fixed command in next oxygen Update for rnd irnd arnd ? Or I must Always use this construct ?

[Charles Pegge]

I'll think about it, Frank, but its all included in chaos.inc which in turn is included in the OpenGl Frameworks.
We might need a choice of random number for different applications.

[Frank Brübach]

oxygen programming technique question

hi charles, may I ask you how I can include a function as fixed command in oxygen?
something like this one?

Code Select Expand

'irnd  16 #sys#sys@0 sys 2560

  int seed=0x12345678

  function irnd(int z1, z2) as int
  ================================
  mov    eax,z2
  sub    eax,z1
  inc    eax
  imul   edx,Seed,0x8088405
  inc    edx
  mov    Seed,edx 'store new seed
  mul    edx 'multiply eax by edx
  return edx+z1
  end Function

I can suppose there's a lot of more to handle isn't it?

regards, frank

[Charles Pegge]

I don't want this inside o2 core yet but you can create your own .inc library of functions. They can be new functions or even override existing functions.

[Frank Brübach]

I understand No Problem Charles thx I will try to make an alternative way and try to implement a rnd2() or irnd2() and rgb() fixed command in oxygen I dont give Up
I am studying also the freebasic source Code of oxygen 2016 and try to learn more about this topic

Nice wednesday