|
The overriding concept of makefiles is the ability to specify the dependencies in a simple tree. But since you are the one who knows which module(s) depend on which, you are the person who will need to create the tree.
|
|
|
|
|
Hello, there is a pseudocode for recursive radix 2 DIT Fast Fourier Transform(page 11,12) at this link.
I have written a code in c++ which does the same, but it doesn't work properly.
For example when I take 1024 datapoints of sin(0.1*x) where x={0,1,...1023}, I get this.
Reverse transform inserted for this gives initial function multiplied by 1024, so it works.
What could be wrong? I tried with value dir and dir/2 inside "Shift" function too.
Here is the code:
Notation: E2-even part, E3-odd part
I work without complex numbers library, so there are both "_re" and "_im" tables.
void FFT(double *tab_re, double *tab_im, double *results_re, double *results_im, int n, int dir) {
if(n==1)
{results_re[0]=tab_re[0]; results_im[0]=tab_im[0]; return;}
int nh=n/2;
double *E2_re=new double [nh];
double *E3_re=new double [nh];
double *E2_im=new double [nh];
double *E3_im=new double [nh];
double *F2_re=new double [nh];
double *F3_re=new double [nh];
double *F2_im=new double [nh];
double *F3_im=new double [nh];
for(int k=0;k<nh;++k) {E2_re[k]=tab_re[2*k];
E2_im[k]=tab_im[2*k];
E3_re[k]=tab_re[2*k+1];
E3_im[k]=tab_im[2*k+1];}
FFT(E2_re,E2_im,F2_re,F2_im,nh,dir);
FFT(E3_re,E3_im,F3_re,F3_im,nh,dir);
Shift(F3_re,F3_im,nh,dir);
for(int k=0;k<nh;++k)
{
results_re[k]=F2_re[k]+F3_re[k];
results_im[k]=F2_im[k]+F3_im[k];
results_re[k+nh]=F2_re[k]-F3_re[k];
results_im[k+nh]=F2_im[k]-F3_im[k];}}
void Shift(double *tab_re, double *tab_im, int n, int v)
{double re,im;
double pi=3.14159265359;
double arg;
for(int i=0;i<n;++i)
{re=tab_re[i];
im=tab_im[i];
arg=v*2.0*pi*i/n;
tab_re[i]=re*cos(arg)-im*sin(arg);
tab_im[i]=re*sin(arg)+im*cos(arg);}}
|
|
|
|
|
If you get the original function back after the reverse, you have probably coded the transform correctly.
The problem is likely to be that your sampling rate is not a multiple of the basic frequency of sin(0.1*x). This means that you get a large FFT component close to the frequency, but you also get "noise" throughout the range, due to the fact that the residues do not cancel out.
I would try taking an FFT of sin(x), sin(2*x), etc., and see if these functions give the expected values.
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
|
|
|
|
|
Thank You for the hint. I have tried with sin(nx), sin(2pi*x/n) and sin(2pi*x*n) too, but results were similar.
The most promising result was for the option with sin(2pi*x*n): here is a result with n=10. Values for x>270 are 0.
I used decimation in frequency FFT instead of decimation in time version, but it still doesn't show good values.
|
|
|
|
|
You lost me with your translation of the code .. page 11 & 12 have the exp function which doesn't appear in your code?
In vino veritas
|
|
|
|
|
The exp function is inside function called "Shift".
As I wrote earlier, I don't use complex numbers library, so there are both tables for real and imagery parts. I used this relation: exp(i*phi)=cos(phi)+i*sin(phi).
|
|
|
|
|
Bonjour, //hi
essayez avec : //try with
arg=v*pi*i/n;
k++); //two time
i++);
|
|
|
|
|
Hello, I do not want to use an MDI app to create new documents of the same kind, like in text processors. Instead I want to be able to open different child windows from the menu. The menu handling is clear. When I go and create a new form with controls in the resources/dialog editor, how can I connect them to what I see in the client area of the child ? The classic kind of business software, you know. A user can open a customer window, then a payment window, a child for envoices, for banking, statics and so on. Normal dialog windows do not fill the client area, they are on top of all. That is not what I am going for. Thank You.
|
|
|
|
|
|
Hallo Victor,
yes I just did. That issue is different. Mine is about connecting the window resource to the canvas of the app. That one from the painter, where all controls are placed.
Thank You
|
|
|
|
|
Member 11883602 wrote: That issue is different. Mine is about connecting the window resource to the canvas of the app. That one from the painter, where all controls are placed.
And how would it differ from what CMultiDocTemplate represets?
|
|
|
|
|
Hello. I got it now. To occupy an SDI/MDI with a formview resource template there is one detail in the project assistant. At the last page one can fill in from what the view derives. The preset is CView, but you must change it to CFormView. That was all. Well, I would have liked to make it an existing project, but this is ok, too. Thank You.
|
|
|
|
|
|
|
In my MFC application, I am doing a custom drawing in my dialog class OnPaint(). I have also created a few controls in dialog template. I have also resized and repositioned some of the controls in the dialog code. When I run my application, the controls are flickering.
Please suggest me how to avoid this?
BOOL CFP::OnInitDialog()
{
CDC *pDC = GetDC(); //Get DC for Dialog's Client Area
pDCTmp->CreateCompatibleDC(pDC); //Create Compatible DC(pDCTmp) for Dialog's Client Area(pDC)
//pDCTmp is a member Variable
pBgBitmap->CreateCompatibleBitmap (pDC, 800, 640 ); //Create Compatible Bitmap(pBgBitmap) for Dialog's Client Area(pDC)
//pBgBitmap->LoadBitmap(IDB_FORESTIMAGE);
pDCTmp->SelectObject(pBgBitmap);
ReleaseDC(pDC);
}
void CFacePlate::OnPaint()
{
CPaintDC dc(this); // device context for painting
// TODO: Add your message handler code here
CRect rect;
rect = rScreen; //rScreen is Client rect
pDCTmp->FillRect(rect,&CBrush(RGB(152, 185, 192))); //pDCTmp member variable is used to draw
.
.
.
.
//Custom drawings using the pDCTmp
}
|
|
|
|
|
I see nothing in your code snippet that causes flickering.
How did you implement the "Custom drawings"?
When does the flickering happen? While resizing only?
Which controls flicker?
|
|
|
|
|
A seperate thread function created already which calls a function UpdateAllViews() as shown below every half a second which in turn calls Invalidate the CFP Dialog. This is done to continuously update some real time numerical values on the dialog. When I remove this line
pFPlate->Invalidate(FALSE);
then there is no flickering on the dialog. But the values are not updated. How to avoid this flickering without affecting the value updation.
void tUpdateAllViews( CMainFrame *pMainFrm )
{
while( 1 )
{
pMainFrm->UpdateAllViews();
Sleep(500);
}
}
void CMainFrame::UpdateAllViews()
{
if(pFPlate->GetSafeHwnd()) //CFP Dialog member variable
{
if(pFPlate->IsWindowVisible())
{
pFPlate->Invalidate(FALSE);
}
}
}
|
|
|
|
|
I'm a little confused by some of your code but generally I think you will
have to override WM_ERASEBKGND so that the background is not erased by the
default processing. Do not call the base class; just return TRUE.
|
|
|
|
|
Yes. done that. But still its flickering. It seems the problem is in the thread which calls the Invalidate for the Dialog.
Please help to find out what is wrong or how to correct the problem
|
|
|
|
|
But why do you call Invalidate if you haven't changed anything in the View?
|
|
|
|
|
1. Do you have to call Invalidate() from a thread? Could you use a timer in the dialog
and only update what is needed instead of invalidating the whole dialog?
2. Are your dialog controls embedded in a TabControl/TabPage? If so you will have to
create a custom TabControl and TabPage to override the OnEraseBackground() in those and
paint the background in a temp dc as well.
3. I'm not sure about this, but you may have to set the dialog style WS_CLIBCHILDREN to
include them in the dialogs clip region. Look at definition in msdn.
|
|
|
|
|
Additionally, I don't know what pFPlate is but if it's a pointer to the dialog,
could you create a function in the dialog to update what you need instead of
calling Invalidate().
|
|
|
|
|
I am not a real fan of MFC but I can tell you what windows API is doing.
Dialog backgrounds paint by WM_CTLCOLORDLG, WM_CTLCOLORSTATIC it used to be WM_CTLCOLOR and I suspect MFC still uses WM_CTLCOLOR because it has a couple of bugs.
Usually what you want to do is return a NULL_BRUSH with GetStockObject(NULL_BRUSH);
So this one if you paint the entire dialog then return a NULL_BRUSH
WM_CTLCOLORDLG message - Windows applications | Microsoft Docs[^]
MFC may use this one and again return a NULL_BRUSH
WM_CTLCOLOR message - Windows applications | Microsoft Docs[^]
That means it doesn't paint the background before it sends you an WM_PAINT 
If you want/need to transparent overlay the bitmap you have to use a transparent colour to stop flashing
void CDemoDialog::OnPaint()
{
CPaintDC dc(this);
dc.TransparentBlt(
10, 10, bmp.bmWidth, bmp.bmHeight,
&pDCTmp,
0, 0, bmp.bmWidth, bmp.bmHeight,
RGB(255, 0, 0));
}
In vino veritas
modified 1-Mar-19 12:54pm.
|
|
|
|
|
I'm generating dialog templates programmatically for a win32 project. A thing I often want to do is size the dialog box such that the distance between the left edge of the client region and the left edge of the leftmost control is the same as that between the right edge of the rightmost control and the right edge of the client region. Since the size of the dialog box as specified in the template, I believe, includes the non-client area, the only way I know of to do this is to use AdjustWindowRect on a RECT representing the desired client region. Since this requires the handle of the window being adjusted, I can't do it until after the dialog has been created. So I was wondering...if I can't ensure equal margins until runtime, how is it possible that one can use the GUI editor Visual Studio provides to create dialogs with equal margins ahead of time? I want to be able to do that too.
|
|
|
|
|
You can select a set of controls in the editor and then use the toolbar tool that centres the group in the dialog. There are tools to centre horizontally or vertically, make equidistant, align together etc.
|
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
