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**psphacker12.** · 09-30-2006, 09:50 PM

i know how to do this in lua but how do i do this in C?..?

**UB3R-W4N-K0N0B1** · 09-30-2006, 09:56 PM

ohh! make an xbox live code gen!

**Twin891** · 09-30-2006, 09:57 PM

There is a C/C++ help thread you know...

**psphacker12.** · 09-30-2006, 10:07 PM

Quote:

Originally Posted by UB3R-W4N-K0N0B1

ohh! make an xbox live code gen!

No requests..

**UB3R-W4N-K0N0B1** · 09-30-2006, 10:08 PM

huh? it was a suggestion.

**Soulphalanx** · 09-30-2006, 10:31 PM

#include <stdlib.h>
i = rand();

Where:

int i;
is a pseudo-random number in the range 0 to RAND_MAX (where RAND_MAX is a manifest defined in <stdlib.h>).

use

**SG57** · 10-01-2006, 12:28 AM

Gahhh.... read the rules psphacker, search atleast a little bit... if all else fails, theres a thread for this, not to meantion its been answered many many times... Next youll probably ask how to create a random numbers between 2 values - start and end - which has been answered many times before in the help thread, as well as when searching google...

Putting in 'random number in C' gave me 118,000,000 using google...

**Moonchild** · 10-01-2006, 04:51 AM

In your main where you intialize everything call
srand(time(NULL));

Then when you want a random number call
rand();

**Slasher** · 10-01-2006, 05:06 AM

I think he's looking for a more specific random number generator. Not some pseudo number.

Code:

#include <time.h>

srand(sceKernelLibcTime(NULL));

/* Get random number */
int getRandomNum(int min, int max)
{
	int diff = max - min;
	int res = (rand() % diff)+min;
	return res;
}

Should work

**yaustar** · 10-01-2006, 06:41 AM

rand() is pseudo anyway. The only 'random' factor used is the seed used with srand(). http://www.random.org/

**Slasher** · 10-01-2006, 07:48 AM

http://forums.qj.net/f-psp-developme...ion-39517.html

Check this out too.

**mannymix03** · 10-01-2006, 07:58 AM

too bad its really not random as a computer cant have a random number

**GmDude66** · 10-01-2006, 08:12 AM

Quote:

Originally Posted by mannymix03

too bad its really not random as a computer cant have a random number

Big deal, it's close enough

**Slasher** · 10-01-2006, 08:12 AM

Quote:

Originally Posted by mannymix03

too bad its really not random as a computer cant have a random number

seeding it does infact make it random.

**FreePlay** · 10-01-2006, 08:16 AM

No, it doesn't, because the sequence of numbers generated will be the same each time you use the same seed. It's pseudo-random based on a mathematical sequence

**Slasher** · 10-01-2006, 08:20 AM

Quote:

Originally Posted by FreePlay

No, it doesn't, because the sequence of numbers generated will be the same each time you use the same seed. It's pseudo-random based on a mathematical sequence

Well...yea, I guess. Damn you.

**Moonchild** · 10-01-2006, 08:22 AM

That's why you seed it with time(NULL). The time is always increasing, so it should never be the same.

**mannymix03** · 10-01-2006, 08:34 AM

Quote:

Originally Posted by homer

That's why you seed it with time(NULL). The time is always increasing, so it should never be the same.

but its still using a formula to derive it, if you really wanted you could figure it out and be able to tell the time from the random sequence

**GmDude66** · 10-01-2006, 08:37 AM

Quote:

Originally Posted by mannymix03

but its still using a formula to derive it, if you really wanted you could figure it out and be able to tell the time from the random sequence

Who the hell would want to do that..

**mannymix03** · 10-01-2006, 08:40 AM

Quote:

Originally Posted by GmDude66

Who the hell would want to do that..

no one, but i mean. Its not perfectly random

**pspcoder05** · 10-01-2006, 11:11 AM

You can also specify the limit.
See....
Just use simple rand() function.

Code:

..
....
.....


int main(void)
{
pspDebugScreenInit();
SetupCallbacks();
int rn; //random number holder
rn=rand()%100;//Where rand generates a random number inside 100;
pspDebugScreenPrintf("Generated Integer:%d",rn);
sceKernelSleepThread();
return 1;
}

See....pretty simple huh?

**SG57** · 10-01-2006, 11:30 AM

Dont you think it'd be best to make the seed sceKernelLibcClock(void );? that returns the # of miliseconds since hte app has started... Seems better than time being seconds...

**Xfacter** · 10-01-2006, 11:34 AM

http://www.psp-programming.com/dev-f...pic.php?t=1076

Make sure to look at the last post if you want it to work right...

**SG57** · 10-01-2006, 11:40 AM

Ok, the truth ehind rand():

Code:

static unsigned long _seed = 0;

long
rand(void)
{
	if (_seed == 0)
		_seed = 1;

	if ((((_seed << 3) ^ _seed) & 0x80000000L) != 0)
		_seed = (_seed << 1) | 1;
	else
		_seed <<= 1;

	return _seed - 1;
}

void
srand(unsigned long new_seed)
{
	_seed = new_seed;
}

Man Im good...

**pspcoder05** · 10-01-2006, 10:44 PM

Wooh....
you really code well.

**Art** · 10-02-2006, 12:14 AM

Quote:

too bad its really not random as a computer cant have a random number

There is noise in the audio input buffer even when no microphone or remote
are connected.
It would be influenced by EMI from the environment, so not truly random,
but the best seed for random numbers on the PSP so far.

You can see the noise by starting this app:
http://home.arcor.de/themirek/pspdev/audioinput.zip
Press Circle and then square.
You don't need to bother plugging a mic or remote in.

09-30-2006, 09:50 PM	#1
psphacker12. likes kittens....awww.... Join Date: Sep 2006 Real First Name: Erik Location: Detroit Just Played: Call of Duty:World at War Posts: 628 Trader Feedback: 0	generating random nums?? i know how to do this in lua but how do i do this in C?..? Last edited by psphacker12.; 09-30-2006 at 10:06 PM..

09-30-2006, 10:31 PM	#6
Soulphalanx Join Date: Sep 2005 Location: TROY Posts: 2,989 Trader Feedback: 0	#include <stdlib.h> i = rand(); Where: int i; is a pseudo-random number in the range 0 to RAND_MAX (where RAND_MAX is a manifest defined in <stdlib.h>). use __________________ [IMG]http://img121.imageshack.us/img121/3852/untitled1copy7rf.png[/IMG] [IMG]http://img99.imageshack.us/img99/9711/newavatarjb9.gif[/IMG] [URL=http://forums.qj.net/showthread.php?t=9733][COLOR=DarkRed]Operation Positive Posting[/COLOR][/URL] [URL=http://forums.qj.net/showthread.php?t=49762][COLOR=Red]Guide to All Guides[/COLOR][/URL] [URL=http://forums.qj.net/showthread.php?t=13798][COLOR=Blue]Posting Guidelines[/COLOR][/URL] [URL=http://forums.qj.net/showthread.php?t=4394][COLOR=Green]Piracy Policy[/COLOR][/URL] [SIZE="3"][URL=http://forums.qj.net/f-general-psp-help-22/t-guide-opening-psp-disassembly-assembly-video-104303.html][COLOR=Red][B][U]PSP Disassembly Assembly Video Tutorial[/U][/B][/COLOR][/URL][/SIZE]

10-01-2006, 12:28 AM	#7
SG57 ...in a dream... Join Date: Jul 2005 Posts: 4,957 Trader Feedback: 0	Gahhh.... read the rules psphacker, search atleast a little bit... if all else fails, theres a thread for this, not to meantion its been answered many many times... Next youll probably ask how to create a random numbers between 2 values - start and end - which has been answered many times before in the help thread, as well as when searching google... Putting in 'random number in C' gave me 118,000,000 using google... __________________ ...you'll never know what it's like... spending your whole life in a dream... Launch a Kitten out of a Cannon and win real cash! Checkout my newly updated site for all my projects (Kitten Cannon, BOXHEAD, Light Cycle 3D)

10-01-2006, 04:51 AM	#8
Moonchild AKA Homer Join Date: Jan 2006 Location: Sweden Posts: 1,779 Trader Feedback: 0	In your main where you intialize everything call srand(time(NULL)); Then when you want a random number call rand(); __________________ Click Here if you want a Winamp Currently Playing Userbar like the one above.

10-01-2006, 05:06 AM	#9
Slasher OMFG Join Date: Jul 2005 Location: Toronto Posts: 2,816 Trader Feedback: 0	I think he's looking for a more specific random number generator. Not some pseudo number. Code: #include <time.h> srand(sceKernelLibcTime(NULL)); /* Get random number */ int getRandomNum(int min, int max) { int diff = max - min; int res = (rand() % diff)+min; return res; } Should work

09-30-2006, 09:56 PM	#2
UB3R-W4N-K0N0B1 Join Date: Sep 2006 Posts: 121 Trader Feedback: 0	ohh! make an xbox live code gen!

09-30-2006, 09:57 PM	#3
Twin891 Join Date: Jul 2006 Location: Canada Posts: 70 Trader Feedback: 0	There is a C/C++ help thread you know...

09-30-2006, 10:08 PM	#5
UB3R-W4N-K0N0B1 Join Date: Sep 2006 Posts: 121 Trader Feedback: 0	huh? it was a suggestion.

10-01-2006, 06:41 AM	#10
yaustar Developer Join Date: Jun 2006 Location: UK Posts: 2,317 Trader Feedback: 0	rand() is pseudo anyway. The only 'random' factor used is the seed used with srand(). http://www.random.org/

10-01-2006, 07:48 AM	#11
Slasher OMFG Join Date: Jul 2005 Location: Toronto Posts: 2,816 Trader Feedback: 0	http://forums.qj.net/f-psp-developme...ion-39517.html Check this out too. Last edited by Slasher; 10-01-2006 at 08:12 AM..

10-01-2006, 08:16 AM	#15
FreePlay Join Date: Dec 2005 Location: h0000000rj Posts: 12,858 Trader Feedback: 0	No, it doesn't, because the sequence of numbers generated will be the same each time you use the same seed. It's pseudo-random based on a mathematical sequence __________________ [qj now fails.]

10-01-2006, 08:22 AM	#17
Moonchild AKA Homer Join Date: Jan 2006 Location: Sweden Posts: 1,779 Trader Feedback: 0	That's why you seed it with time(NULL). The time is always increasing, so it should never be the same. __________________ Click Here if you want a Winamp Currently Playing Userbar like the one above.

10-01-2006, 11:30 AM	#22
SG57 ...in a dream... Join Date: Jul 2005 Posts: 4,957 Trader Feedback: 0	Dont you think it'd be best to make the seed sceKernelLibcClock(void );? that returns the # of miliseconds since hte app has started... Seems better than time being seconds... __________________ ...you'll never know what it's like... spending your whole life in a dream... Launch a Kitten out of a Cannon and win real cash! Checkout my newly updated site for all my projects (Kitten Cannon, BOXHEAD, Light Cycle 3D)

10-01-2006, 11:34 AM	#23
Xfacter Developer Join Date: May 2006 Posts: 114 Trader Feedback: 0	http://www.psp-programming.com/dev-f...pic.php?t=1076 Make sure to look at the last post if you want it to work right... __________________ For game downloads and development updates, check out my website. http://xfacter.wordpress.com/

10-01-2006, 11:40 AM	#24
SG57 ...in a dream... Join Date: Jul 2005 Posts: 4,957 Trader Feedback: 0	Ok, the truth ehind rand(): Code: static unsigned long _seed = 0; long rand(void) { if (_seed == 0) _seed = 1; if ((((_seed << 3) ^ _seed) & 0x80000000L) != 0) _seed = (_seed << 1) \| 1; else _seed <<= 1; return _seed - 1; } void srand(unsigned long new_seed) { _seed = new_seed; } Man Im good... __________________ ...you'll never know what it's like... spending your whole life in a dream... Launch a Kitten out of a Cannon and win real cash! Checkout my newly updated site for all my projects (Kitten Cannon, BOXHEAD, Light Cycle 3D)

10-01-2006, 10:44 PM	#25
pspcoder05 Join Date: Sep 2006 Posts: 167 Trader Feedback: 0	Wooh.... you really code well.

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generating random nums??