C / C++ / MFC

Re: how to solve riccati equation differential in c++ or java

15-Dec-15 3:23

You will get a better answer by asking in English.

Daniel Pfeffer15-Dec-15 22:08

Daniel Pfeffer

15-Dec-15 22:08

There are many numeric approaches to solving sets of differential equations. As long as the numerical equations can be represented as a set of functions of the form:

dy(x)/dx = f(x)

you should find an appropriate solver. One family of numerical solvers is the Runge-Kutta family, and there are many others. Any numerical analysis book should have details.

If you have an important point to make, don't try to be subtle or clever. Use a pile driver. Hit the point once. Then come back and hit it again. Then hit it a third time - a tremendous whack.

--Winston Churchill

Strange compiler error

ForNow14-Dec-15 7:14

ForNow

14-Dec-15 7:14

Hi,

I got this strange compiler error here is the source line

C++

for (i=MAX_DECIMAL_DIGITS-1, j=MAX_DECIMAL_DIGITS-1-effective_addr2;
        i >= 0; i--, j--)

The solution/project project compiles cleanly in a different directory where the other source files are different but the source file is the same

thanks

Re: Strange compiler error

Richard MacCutchan14-Dec-15 7:50

Re: Strange compiler error

14-Dec-15 7:50

That error message is a bit confusing. It mentions a source line at first, but then shows an error in the linker.

ForNow14-Dec-15 7:58

ForNow

14-Dec-15 7:58

I was able to generate a "debug" version of the code and it seems to run as fast
I guess I have to look at my properties and see if any entry is incorrect

I look at the linker section
Thanks so much

Re: Strange compiler error

Jochen Arndt14-Dec-15 8:05

Jochen Arndt

14-Dec-15 8:05

I had such compiler errors in the past with older VC versions.

Quote:
To work around this problem, try simplifying or changing the program near the locations listed above.

I always solved the problem following the above. There was one case where it could be solved by just exchanging two lines of code. In the other cases, I re-ordered some code or moved code to an additional function.

I don't remember if I had the linker error afterwards too. But it is obviously sourced by the compiler error (the compiler exits immediately when that error occurs).

Proposal of a new C/C++ precompiler project

Javier Luis Lopez14-Dec-15 0:52

Javier Luis Lopez

14-Dec-15 0:52

Problems:
- C, C++ declining due python and other high level languages
- C, C++ programming structure comes from Jurassic era
- Programmers are always redesigning the wheel
- New software are heavy weight, so they takes lots of time to upload from hard disks
- Every time a new project is written it must be copied the functions so perhaps it exist different functions version in the hard disk
- In the hard disk exists dozen of projects with files and functions distributed in a unclear structure
Proposed solution:
To design a new precompiler (perhaps based in geany) that performs the following tasks:
- Look for all functions in a function directory
- Write them in a tree
- The user drags and drop the functions from the tree using the mouse
- The pre compiler writes the C program to be compiled using only the needed functions
- More over the precompiler can access to web sites with functions written by other users
- In the project it will appear a dictionary that advises what functions are used
- If a function is modified it advises of the affected projects in order to write it with different name
- It will be easily readable in a tree the functions dependence with other functions
- Build the makefile
- User can navigate through the project function tree structure to see one function
- The precompiler adds multithreading headers if it is possible when some functions works in parallel
- The precompiler can change the calling variable type with others (example double to float) and modifying internal function type definitions accordingly

As example the user can write an only one file named “matrix.cpp” that contains ALL matrix functions like the followings. The commented lines before explain the function.

//matrix2 is the inverse of matrix1. The matrix1 and 2 are squared
//matrices of NxN dimension
matrix_inverse(double *matrix1,double *matrix2,long N)

//high speed inverse of two arrays
matrix_inverse3x3(double *matrix1,double *matrix2) 

//matrix3=matrix1 x matrix2. The dimension of the 3 matrices is NxN
matrix_multiplier(double *matrix1,double *matrix2,double *result,long N)

How the function tree can be seen:
http://s12.postimg.org/q50hwfpnh/Proposal_of_a_modern_C.png

Richard MacCutchan14-Dec-15 4:12

14-Dec-15 4:12

Wrong place; please read http://www.codeproject.com/Messages/2922875/HOW-TO-ASK-A-QUESTION.aspx[^].

Javier Luis Lopez14-Dec-15 22:21

Javier Luis Lopez

14-Dec-15 22:21

"Wrong place; please read"
May be but I did not found a better place than "General Discussions>C-C++" and I can not move the post to other place and must not remove the post Frown | :(

David Crow15-Dec-15 6:47

David Crow

15-Dec-15 6:47

So what exactly is your C / C++ / MFC question?

Javier Luis Lopez17-Dec-15 0:26

Javier Luis Lopez

17-Dec-15 0:26

There are some questions, not one:
- If anyone is interested in help me to make the precompiler (I can extract the functions but not display them to drag&drop using mouse)
- What is the right forum or subforum (in codeproject if possible)
- If it exist a code editor where the precompiler can be added

Code Signing Verification

david2111417-Dec-15 11:31

david21114

17-Dec-15 11:31

Don't you think your first two assumptions are a bit like click-baiting for a response?

One approach is to make your thesis into providing a "novice" or a Java or C# developer the ability to rapidly create a C/C++ application without having to know how to use pointers or code in the language. Cool | :cool:

Look back at something called "Software through Pictures" STP, and there is another product one of the process control companies makes for modeling potential solutions.

Good luck with that.

Richard Andrew x6412-Dec-15 19:27

Richard Andrew x64

12-Dec-15 19:27

I understand that I can use WinVerifyTrust()[^] to validate a PE file's signature.

But it looks as if this will only tell me if the signature is A) valid and B) from a trusted publisher.

How do I verify that the signature is from a specific publisher?

For instance, I'm worried someone could strip a signature, modify the file, then sign it with their own certificate. The signature in this case would check out, but it wouldn't be from the original publisher.

Is there a way to verify the specific publisher, or is there something about code signing I don't understand?

The difficult we do right away...
...the impossible takes slightly longer.

Re: Code Signing Verification

Garth J Lancaster12-Dec-15 19:59

Garth J Lancaster

12-Dec-15 19:59

I would have thought CryptQueryObject was heading down the path you wish to travel (gawd, what have I swallowed, a dictionary ?) .. https://support.microsoft.com/en-us/kb/323809[^]

Re: Code Signing Verification

Richard Andrew x6412-Dec-15 20:03

Richard Andrew x64

12-Dec-15 20:03

Bingo! Thank you very much. Big Grin | :-D

The difficult we do right away...
...the impossible takes slightly longer.

Need a suggestion in searching a file

VISWESWARAN199812-Dec-15 6:18

12-Dec-15 6:18

Sir, I have coded a program to get a string form a file and compare the string present in the file and which I have defined in my program.
I am using

C++

FILE *opn = fopen("C:\\test.txt","r");

to achieve this and "strcmp" to compare the strings.
I need a suggestion for implementing my code to get the strings of all files present in my computer and comparing with the string which I have defined in the program so that I can find the presence of that file in my computer.
Kindly help me.

Richard MacCutchan12-Dec-15 6:42

12-Dec-15 6:42

You can use the FindFirstFile function[^] to start a search for files in a directory tree. As you get each file's name you can then read its contents and search for the text. Do not be surprised if it takes a lot of time.

You can also read some of the suggestions that Google finds[^].

VISWESWARAN199812-Dec-15 7:00

12-Dec-15 7:00

Sorry Sir, I think I have not explained my question correctly.I am looking for function which gets the string(will be equal irrespective of the file size) of all files present in the computer and compares with the string which I have defined in my program.More precisely I am looking for a program which searches for the "strings" irrespective of their names.

Richard MacCutchan12-Dec-15 7:23

12-Dec-15 7:23

Yes I understand your question. And the way to do it, is to get the list of all files in your target set, and then read each file in turn in order to find the string. You can use some the strXXX functions[^] to speed up the searching.

VISWESWARAN199812-Dec-15 8:29

12-Dec-15 8:29

Sir, What if I do if I run the executable on another computer.I have only "C:\\ and D:\\" drives if I run the executable on another computer which has "C:\\ D:\\ E:\\ " drives my code ultimately fails Frown | :(

.How can I get the list of all files on the computer on which my executable runs.I sincerely thank you for giving me the excellent link for speed up my searching.

Richard MacCutchan12-Dec-15 9:32

12-Dec-15 9:32

You really need to learn how to do some more research for yourself. How do you get a list of all the drives? Type "Windows list drives C++" into Google and start reading.

VISWESWARAN199812-Dec-15 10:13

12-Dec-15 10:13

Yes, this ("Windows list drives C++") didn't strike to my mind.
Thank you sir for your kind help.