How to get value of STL <vector> by iterator? - C / C++ / MFC Discussion Boards

Mediate16-Feb-04 3:18

16-Feb-04 3:18

Hi all!

This is a very simple problem, please give me a nice pointer to the solution.

I'm writing long numbers in a textfile with ofstream. The numbers are relatively big but I need the precision. Now ofstream writes the numbers as:
1.17308e+006 instead of 1173080. I'm loosing precision with this, how can I avoid this and make shure it just writes the real numbers (in the not scientific way)?

Thanks!

Aram

Re: avoid scientific numbers

Tim Smith16-Feb-04 4:10

Tim Smith

16-Feb-04 4:10

How are you losing precision? As long as all significant digits are displayed in the scientific version, it is just as good if not better. Single precision only has 7.2 significant digits.

http://babbage.cs.qc.edu/courses/cs341/IEEE-754references.html[^]

Tim Smith

I'm going to patent thought. I have yet to see any prior art.

Re: avoid scientific numbers

Sebastian Schneider16-Feb-04 23:47

Sebastian Schneider

16-Feb-04 23:47

I suppose you are talking about "long floating point values", not "long int values".

Actually, you are not "loosing" precision. You are just limited to the precision "float" or "double" offers. Not every number can be represented using a double or float. You still only have so many bits to store your floating point variable in.

And as usual, you can still define your own variable type and write all the calculation and transformation stuff yourself Wink | ;)

Cheers
Sebastian

Re: avoid scientific numbers

Mediate17-Feb-04 0:21

Mediate

17-Feb-04 0:21

Hi!

I solved it, it was indeed a very stupid little problem. I did the long value * 0.5, but i forgot to cast it (like: (long)(counter*0.5);) that was the trick, thanks anyway!

Big Grin | :-D

How to add a custom search handler in Start Menu->Search

PravinSingh16-Feb-04 2:34

PravinSingh

16-Feb-04 2:34

Hi everyone,

I want to add my custom search handler in Start Menu -> search options. I somewhere found that I've to make a new subkey in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\FindExtensions\Static . I made that subkey and filled with appropriate values also, but still it is not working.

Now foxed ! Any ideas ??

Pravin...

Re: How to add a custom search handler in Start Menu->Search

Sebastian Schneider16-Feb-04 22:07

Sebastian Schneider

16-Feb-04 22:07

I have been doing a Context Menu Handler these days.

The first thing I would do is to check the "Shell Programming"-Section of CP.

I used Michael Dunn's Excellent Tutorials to create my own handler.

I hit some obstacles, though:

Have the most recent Platform SDK installed.
Make the proper Registry Entries.
Register your COM-DLL using "regsvr32 path\filename.ext"

Restart your Explorer (Completely. On Win2000 and WinXP you can do that by logging of and back on again.)

Make sure your CLSID is listed in the APPROVED section of the registry, should you not have admin privileges. Check M. Dunns Tutorials on how to do that.

This is about all the advice I can give.

Cheers
Sebastian

PrintDC to CDC

Yusak16-Feb-04 2:02

Yusak

16-Feb-04 2:02

How to copy Print DC to CDC or otherwise ?

I've used CreateCompatibleDC() and BitBlt() but it can't work why ?

Thanks

How to get value of STL <vector> by iterator?

vgrigor16-Feb-04 1:51

vgrigor

16-Feb-04 1:51

If I define STL vector, not bu pointer, but by value
as:

<br />
<br />
typedef vector<CVariableShift> type_DevStrVector;<br />
<br />
struct CVariableShift<br />
{<br />
int i;<br />
};<br />

than how to get copy of stored variable
by iterator?

Only possible bu conversion to pointer ? as :

<br />
<br />
int j = it->i; // works but only for member of struct<br />
<br />
 l_VariableShift = *(CVariableShift*)(&it); //<br />
                  //proble - not suitable, not normal, not natural<br />
<br />
  //not as usual and suitable as in map :<br />
  //l_VariableShift = it->second;<br />
 <br />

Is it possible to works without ugly conversion?

thanks.

Re: How to get value of STL <vector> by iterator?

Mike Dimmick16-Feb-04 2:39

Mike Dimmick

16-Feb-04 2:39

I think you're asking the following. I have a vector<int> and an iterator of type vector<int>::iterator (or const_iterator). How do I get the value that the iterator points to?

vector<int>::iterator it;
 
// ... omitted operations to set it ...
 
int iVal = *it;

Re: How to get value of STL <vector> by iterator?

vgrigor16-Feb-04 2:50

vgrigor

16-Feb-04 2:50

yes,
thanks.

Excel protection question

Tzoockee16-Feb-04 0:51

Tzoockee

16-Feb-04 0:51

I'm creating a .xls file using a third-party com component. However this component is unable to protect the sheet using a password.

Does anybody knows a way I can protect the sheet using vc++ (without having microsoft excel installed) ?

creatting a transparent text GIF using CXImage

emmatty16-Feb-04 0:43

emmatty

16-Feb-04 0:43

hello friends,

We are doing a project in vc++ for image processing .We used your class(CXImage) in our project for converting user typed text into transparent GIF image. We used the following steps for our requirement.

Note: Operating System : Win XP Professional ,
Development Tool : VC++ 6.0.

1)Create a memoryDC

2)Created a compatible bitmap with the dialog

3)selected the bitmap into MemoryDC

4)Draw Text on that DC

5) Created a CXImage object and passed Bitmap handle to CXImage member function called CreateFromHBITMAP

6) We used the function Save() to save that image.

But the problem ia that we can insert the Image to Frontpage but the image is not visible.
Following code is extracted from our project
void CTestCXImageDlg::OnCreateBMP()
{
CDC memDC;
CBitmap bitmap;
CBrush brush(RGB(255,255,255));
CFont font;
UpdateData();

font.CreateFontIndirect(&logfont);

if(memDC.CreateCompatibleDC(GetDC()))
{
if(bitmap.CreateCompatibleBitmap(GetDC(),200,50))
{
memDC.SelectObject(bitmap);

memDC.SetBkColor(RGB(255,255,255));
memDC.FillRect(CRect(0,0,200,50),&brush);
CRect rect(60,15,200,50);
SetTextColor(memDC.m_hDC,RGB(0,255,0));

memDC.SelectObject(&font);

memDC.DrawText(m_Text,&rect,DT_END_ELLIPSIS | DT_CENTER );

CxImage img1;
img1.CreateFromHBITMAP((HBITMAP)bitmap.m_hObject);

img1.Save("c:\\imgtest.gif",1);
.
.
.
.

eagerly waiting for your response

How to detect the different regions of two images

Arcrest16-Feb-04 0:29

Arcrest

16-Feb-04 0:29

Hi, everybody

some one know the algorithm of detecting different regions of two images(with the same size),or give me a link where related information can be found.
My application needs that,but my knowledge about digital image processing is not enough.

Thanks.

Web Browser control

TrungHuynh16-Feb-04 0:09

TrungHuynh

16-Feb-04 0:09

Hi
I create a Dialog, and place a WebBroser control on it.

when user insert one media (Window media, Real, QuickTime, Flash). I bulid html string and view on Web Browsercontrol(depend on file to insert, i naviagate from memory use this string (put_innerHtml).

this my code:

LPDISPATCH lpDispatch = NULL;
IHTMLDocument2* lpHtmlDocument= NULL;
IHTMLElement* lpBodyElm = NULL;

lpDispatch = m_WebCtrlPreview.GetDocument();
if(lpDispatch)
{
lpDispatch->QueryInterface(IID_IHTMLDocument2, (void**)&lpHtmlDocument);
lpDispatch->Release();
}
if(lpHtmlDocument)
{
lpHtmlDocument->get_body(&lpBodyElm);
lpHtmlDocument->Release();
}
if(lpBodyElm)
{
BSTR bstrHtml = szHtmlPreview.AllocSysString();
lpBodyElm->put_innerHTML(bstrHtml);
SysFreeString(bstrHtml);
lpBodyElm->Release();
}

szHtmlPrivew is ok, it contains html string to preview media.

My Application run well, But when i insert a Quick Time movie (*.mov), it play on Web Browser control, and then i insert another kind of media, my application will appears a critical error.

HELP ME

Regards
Trung Huynh

Same hotkey for different dialogs in the same MFC program ??

bjolletts16-Feb-04 0:08

bjolletts

16-Feb-04 0:08

Hi
I have a MFC-dialog program with a list in it. I have assigned F5 as a hotkey to update the list through the RegisterHotKey function. This works fine

But from the main window I want to open another dialog with a different list in it. I want to use F5 as a update-hotkey in this dialog too .. but I cant get it to work. F5 only updates the list in the main dialog.

I thought that a RegisterHotKey registered a hotkey for the whole system so that I can capture it in every dialog in my program ??

Any help is much appreciated !

Re: Same hotkey for different dialogs in the same MFC program ??

David Crow16-Feb-04 2:27

David Crow

16-Feb-04 2:27

How are you calling RegisterHotKey()?

A rich person is not the one who has the most, but the one that needs the least.

Re: Same hotkey for different dialogs in the same MFC program ??

bjolletts16-Feb-04 3:15

bjolletts

16-Feb-04 3:15

I do it like this:

In the maindialogs OnInit-function:
RegisterHotKey(GetSafeHwnd(), m_IDHotKey, NULL, VK_F5);

And add this to the messagemap in every dialog that should use the hotkey:
ON_MESSAGE(WM_HOTKEY,OnHotKey)

And the OnHotKey function looks like this:

LRESULT CFingerIDAdminDlg::OnHotKey(WPARAM wParam, LPARAM lParam)<br />
{<br />
   // Do stuff	<br />
}

It only works for the main dialog ... a F5-keystroke in the child window registrates as a F5-key in the main window. I thought that the WM_HOTKEY-message was going to be handled by the dialog that is active ??

Re: Same hotkey for different dialogs in the same MFC program ??

David Crow16-Feb-04 4:27

David Crow

16-Feb-04 4:27

Have you used Spy++ to see the messages that are being received by both the main window and the child dialogs?

A rich person is not the one who has the most, but the one that needs the least.

Re: Same hotkey for different dialogs in the same MFC program ??

Maximilien16-Feb-04 8:16

Maximilien

16-Feb-04 8:16

me think you need to put the handler in all the different dialogs ?

Maximilien Lincourt
Your Head A Splode - Strong Bad

linck

Anonymous15-Feb-04 23:49

Anonymous

15-Feb-04 23:49

I have used FindNextFile for take all file in a directory
but now i have need to know if the current return from to FindNextFile is a link
How can i do?

Re: linck

David Crow16-Feb-04 2:28

David Crow

16-Feb-04 2:28

Check to see if it has a .lnk extension.

A rich person is not the one who has the most, but the one that needs the least.

Re: link

Anonymous16-Feb-04 2:44

Anonymous

16-Feb-04 2:44

I dont have an extention.
This files are in a UNIX ambient

Re: link

David Crow16-Feb-04 4:43

David Crow

16-Feb-04 4:43

What constitutes a shortcut on a Unix box (they used to be called nodes) is different than what constitutes a shortcut on a Windows box. There is no way for a Windows box to "ask" a Unix box if such-and-such file is a shortcut or not.

Re: link

Steve S16-Feb-04 4:54

Steve S

16-Feb-04 4:54

That's true. Unless you can execute something like a stat() on the file at the UNIX end, you have no way of determining that it is anything other than a regular file. You can't even tell if it's a file with multiple hard links, much less something more esoteric, like a soft link or a device file.

Steve S

Difference between delete and delete[]

Cedric Moonen15-Feb-04 23:08

Cedric Moonen

15-Feb-04 23:08

Hello !
Juste a little question.

What is exactly the difference between delete and delete[] ?
Is the second used to delete memory allocated for more than one element and the first when only one element was allocated ?

Thanks

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