C / C++ / MFC

6-Dec-02 0:27

Dear all,

I was wondering if there is a way to generate random gaussian numbers with Visual C++.
Borland Builder has the option randg to do just this.

Many many thanks

Chun Te

Rickard Andersson²⁰6-Dec-02 0:45

Rickard Andersson²⁰

6-Dec-02 0:45

Chun Te, Ewe wrote:
gaussin

What is that?

look up rand() in MSDN Library

Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!

Chun Te, Ewe6-Dec-02 0:52

6-Dec-02 0:52

Sorry for the typo.

The rand() just generates random numbers but not gaussian/normal distribution numbers.

Chun Te

Rickard Andersson²⁰6-Dec-02 1:02

Rickard Andersson²⁰

6-Dec-02 1:02

Chun Te, Ewe wrote:
gaussian

Sorry, but I don't know what a gaussian number is! Frown | :(

Try go to www.msdn.microsoft.com and type in "gaussian" in the search field of "MSDN Library" and then see if you find something.

Cheers! Smile | :)

Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!

Daniel Turini6-Dec-02 1:24

Daniel Turini

6-Dec-02 1:24

Rickard Andersson wrote:
Sorry, but I don't know what a gaussian number is!

It's not a gaussian number, it's a gaussian distribution. Let's pick a simple example: if you plot people's weight x #number of people with a specific weight, you'll get a gaussian distribution: most samples will concentrate on the middle of the graphic and less people on the borders.
Gaussian distribution are also know as Normal distributions. It's know as the "bell curve" too. A picture worth more than a thousand words. See This article[^]

I see dumb people

Daniel Turini6-Dec-02 1:19

Daniel Turini

6-Dec-02 1:19

See This article[^]

I see dumb people

Chun Te, Ewe6-Dec-02 1:24

6-Dec-02 1:24

Thanks...

jhwurmbach6-Dec-02 1:20

jhwurmbach

6-Dec-02 1:20

You did not even try to search CP for it, did you?
Its here[^]for example.

--
"My opinions may have changed, but not the fact that I am right."
Found in the sig of Herbert Kaminski

Daniel Turini6-Dec-02 1:25

Daniel Turini

6-Dec-02 1:25

Hehehe, I got you by a minute!

I see dumb people

Chun Te, Ewe6-Dec-02 2:25

6-Dec-02 2:25

I've found a mathematical formula to do this now. It assume zero mean and it is written in MatLab.

sigma = 2; %The std deviation<br />
x1 = rand(1000,1); %Linear rand number between 0.0 to 1.0<br />
x2 = rand(1000,1);<br />
<br />
z = sqrt(-2*sigma*log(x1)) * cos(2*pi*x2);

the log here is ln, that is log to the base e. Now all we need is just to put it in C.

Thanks to all who replied my post.

Gary Kirkham6-Dec-02 5:02

Gary Kirkham

6-Dec-02 5:02

You can use the code you listed to generate normal variates, but I believe you will get garbage out in the tails of the distribution. The random number generator that is packaged with C is not very good. I suggest you find a better one...there are plenty of them out on the web.

Here is an example

http://www.cs.wm.edu/~va/software/park/park.html

Gary Kirkham

A working Program is one that has only unobserved bugs

Chun Te, Ewe6-Dec-02 5:47

How to detect whether the balloon tips of tray icon has been clicked or timeout on Win2K?

6-Dec-02 5:47

Thanks for the suggestion. I look into it.

Lines not drawing right

S O S6-Dec-02 0:19

S O S

6-Dec-02 0:19

I am trying to do a grid on a window, but it's not working right.
It is a MDI program using MFC.

When I scroll the window by clicking on the scrollbar(pagefull), it works fine
When I scroll by clicking on the scroll arrow, no new grid lines get drawn
When I scroll by dragging the scroll button, only some new grid liens get drawn
I have made the window using the CS_HREDRAW | CS_VREDRAW class style.

The window is made of 1026x1026 tiles, each tile being 16x16 pixels

	CRect r;<br />
	VERIFY(dc.GetClipBox(&r) != ERROR);<br />
<br />
	CBrush *b = new CBrush(theApp.m_gridColor), *ob;<br />
	CPen *p = new CPen(PS_SOLID, 1, theApp.m_gridColor), *op;<br />
<br />
	ob = (CBrush*)dc.SelectObject(b);<br />
	op = (CPen*)dc.SelectObject(p);<br />
<br />
	x = r.left >> 4;<br />
	x2 = r.right >> 4;<br />
	y = r.top >> 4;<br />
	y2 = r.bottom >> 4;<br />
<br />
	// Just vertical for now<br />
<br />
	for (Sint32 i = x; i < x2; i++)<br />
	{<br />
		dc.MoveTo(i << 4, r.top);<br />
		dc.LineTo(i << 4, r.bottom);<br />
<br />
		if (i % theApp.m_thickGridInterval == 0)<br />
		{<br />
			dc.MoveTo((i << 4) + 1, r.top);<br />
			dc.LineTo((i << 4) + 1, r.bottom);<br />
		}<br />
	}

ForrestSong5-Dec-02 22:40

ForrestSong

5-Dec-02 22:40

How to detect whether the balloon tips of tray icon has been clicked or timeout on Win2K?

On WinXP, I can receive the message NIN_BALLOONTIMEOUT and NIN_BALLOONUSERCLICK when balloon hide because timeout or click on it. But on Win2K, I have got nothing.

Advise please.

Thanks in advance!

Sincerely yours,
Forrest;P

Re: How to detect whether the balloon tips of tray icon has been clicked or timeout on Win2K?

ForrestSong15-Dec-02 14:55

ForrestSong

15-Dec-02 14:55

It's better idea to get the position of the icon on system tray.

Please advise how to get the position.

Thanks.

Forrest

An application run

Mazdak5-Dec-02 21:57

5-Dec-02 21:57

How can I check if there is one thread from an application run now?(Not my own application,for example Outlook express is run now or not)

Mazy

"And the carpet needs a haircut, and the spotlight looks like a prison break
And the telephone's out of cigarettes, and the balcony is on the make
And the piano has been drinking, the piano has been drinking...not me...not me-Tom Waits

Re: An application run

Prem Kumar6-Dec-02 1:50

Prem Kumar

6-Dec-02 1:50

Probably what you mean is if atleast one application instance
is running ?

What you need is to just enumerate the process list
and look at the exe or the program name.
Process32First, Process32Next.

Re: An application run

Mazdak6-Dec-02 4:42

6-Dec-02 4:42

Thanks,I'll take alook at them. Smile | :)

Mazy

"And the carpet needs a haircut, and the spotlight looks like a prison break
And the telephone's out of cigarettes, and the balcony is on the make
And the piano has been drinking, the piano has been drinking...not me...not me-Tom Waits

Connect to internet

Mazdak5-Dec-02 21:55

5-Dec-02 21:55

Is there any way that I can find out I'm connected to internet or not in my application?

Mazy

"And the carpet needs a haircut, and the spotlight looks like a prison break
And the telephone's out of cigarettes, and the balcony is on the make
And the piano has been drinking, the piano has been drinking...not me...not me-Tom Waits

Re: Connect to internet

Rickard Andersson²⁰5-Dec-02 22:31

Rickard Andersson²⁰

5-Dec-02 22:31

I've already answered this question, but here is it again:

#include <ras.h>


bool IsConnected()
{
   LPRASCONN TRasCon;
   RASCONNSTATUS Tstatus;

   DWORD lg;
   DWORD lpcon;
   bool lReturn;

   TRasCon->dwSize = 412;
   lg = 256 * TRasCon->dwSize;
   lReturn = false;

   if( RasEnumConnections(TRasCon, &lg, &lpcon) == 0 )
   {
       Tstatus.dwSize = 160;
       RasGetConnectStatus(TRasCon->hrasconn, &Tstatus);

       lReturn = ( Tstatus.rasconnstate == 0x2000 );
   }

   return( lReturn );
}

But this time I will say it's not my code! Smile | :)

Rickard Andersson@Suza Computing
C# and C++ programmer from SWEDEN!
UIN: 50302279
E-Mail: nikado@pc.nu
Speciality: I love C#, ASP.NET and C++!

Re: Connect to internet

Mazdak5-Dec-02 23:26