C / C++ / MFC

Re: what's the point? do{...}while(FALSE);

8-Feb-08 9:35

WalderM wrote:
It's better than using the ugly GOTO method.

better how? If you mean more readable I would argue that at best it is indistinguishably better.

led mike

Nemanja Trifunovic8-Feb-08 10:06

Nemanja Trifunovic

8-Feb-08 10:06

WalderMt's better than using the ugly GOTO method.

I agree that this code is most probably the replacement for goto, but dissagree that it is better. It is even worse, because it hides the intention.

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utf8-cpp

Calc can, but my code can't

Waldermort8-Feb-08 7:30

8-Feb-08 7:30

After a user click, I am pulling a value from a control, converting this into a decimal value and relaying it to another control. The theory is correct, but I just cannot get my code to produce the correct value. This is the formula:

double dZoomFactor = 1 / ( 1 << ( 16 - dwId ) );

where dwId is an integer value between 1 and 16;

In theory:

dZoomFactor = 1 / ( 1 << ( 16 - 1 ) );<br />
dZoomFactor = 1 / ( 1 << 15 );<br />
dZoomFactor = 1 / 32768;<br />
dZoomFactor = 0.000030517578125;

But, the output is always a flat '0.0'. What am I missing?

Waldermort

led mike8-Feb-08 8:05

8-Feb-08 8:05

double dZoomFactor = 1.0 / 32768.0;

led mike

Waldermort8-Feb-08 8:09

8-Feb-08 8:09

That comes out as 3.0517578125000000e-005. Wish I payed more attention to maths back in school. Right now I'm trying to find out what that e-005 means.

Waldermort

CPallini8-Feb-08 8:14

CPallini

8-Feb-08 8:14

WalderMight now I'm trying to find out what that e-005 means.

It means 10^-5, i.e.

3.0517578125000000e-005 = 0.000030517578125000000

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

Waldermort8-Feb-08 8:19

8-Feb-08 8:19

Thankyou thankyou thankyou. I have been on google for the last hour trying to find the meaning of that, but every page seems to think it's a universally understood system, kinda makes me feel stupid Sigh | :sigh:

Anyway, my code is now working. Thanks for the help guys Big Grin | :-D

Waldermort

led mike8-Feb-08 8:28

http://en.wikipedia.org/wiki/Scientific_notation[^]

8-Feb-08 8:28

led mike

Waldermort8-Feb-08 8:34

8-Feb-08 8:34

Thanks for the link, but the 'great firewall of china' prevents me from accessing wikipedia Cry | :((

Waldermort

David Crow8-Feb-08 8:26

David Crow

8-Feb-08 8:26

WalderMouble wrote:
dZoomFactor = 1 / ( 1 << ( 16 - dwId ) );
dZoomFactor = 1 / ( 1 << ( 16 - 1 ) );
dZoomFactor = 1 / ( 1 << 15 );
dZoomFactor = 1 / 32768;
dZoomFactor = 0.000030517578125;

You should probably be using double constants (e.g., 1.0, 16.0), so that the math library is properly initialized.

BTW, your name wreaks havoc in the Quote Selected Text feature. It inserts a malformed </b> tag.

"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Waldermort8-Feb-08 8:30

C++ library supported DLL

8-Feb-08 8:30

That's exactly what I was doing wrong, but that exponent was giving me a real headache, I thought the wrong values were coming out. I hate floating point maths!

Waldermort

George_George8-Feb-08 5:50

George_George

8-Feb-08 5:50

Hello everyone,

Are there some formal documents about which physical files contain C++ related libraries' implementation on Windows (i.e. something like mscvp*, to run and build C++ application, all required static lib, import lib and DLL)?

How about the physical files for C (i.e. CRT) and for all Windows API?

BTW: maybe my question should be asked in another way -- the frequently used DLLs (like user32.dll) and related functions, import libraries and static libraies for Windows platform?

thanks in advance,
George

led mike8-Feb-08 6:38

8-Feb-08 6:38

George_George wrote:
Are there some formal documents about which physical files contain C++ related libraries' implementation on Windows

No. And if it they did exist you certainly would not find them on the Microsoft web site. Roll eyes | :rolleyes:

led mike

George_George8-Feb-08 22:04

George_George

8-Feb-08 22:04

Thanks led mike,

What are the frequently used DLLs on Windows and their related functions, like user32.dll? Any referred link about this?

regards,
George

Hamid_RT10-Feb-08 21:17

Hamid_RT

10-Feb-08 21:17

What do you need exactly?