I have some problems when I do simulation for my Simulink program, it says
_outpw() function not defined
Should i try to find some other function to replace it?
I have put this head source (conio.h) in the Matlab folder, but it doesn't work.
Related
This question already has answers here:
"Undefined function 'function_name' for input arguments of type 'double'."
(3 answers)
Closed 5 years ago.
I'm a new user of Matlab, can you please help:
I have the following code in an .M file:
function f = divrat(w, C)
S=sqrt(diag(diag(C)));
s=diag(S);
f=sqrt(w'*C*w)/(w'*s);
I have stored this file (divrat.M) in the normal Matlab path, and therefore I'm assuming that Matlab will read the function when it's starting and that this function therefore should be available to use.
However, when I type
>> divrat(w, C)
I get the following error
??? Undefined function or method 'divrat' for input arguments of type 'double'.
What is the error message telling me to do, I can't see any error in the code or the function call?
You get this error when the function isn't on the MATLAB path or in pwd.
First, make sure that you are able to find the function using:
>> which divrat
c:\work\divrat\divrat.m
If it returns:
>> which divrat
'divrat' not found.
It is not on the MATLAB path or in PWD.
Second, make sure that the directory that contains divrat is on the MATLAB path using the PATH command. It may be that a directory that you thought was on the path isn't actually on the path.
Finally, make sure you aren't using a "private" directory. If divrat is in a directory named private, it will be accessible by functions in the parent directory, but not from the MATLAB command line:
>> foo
ans =
1
>> divrat(1,1)
??? Undefined function or method 'divrat' for input arguments of type 'double'.
>> which -all divrat
c:\work\divrat\private\divrat.m % Private to divrat
As others have pointed out, this is very probably a problem with the path of the function file not being in Matlab's 'path'.
One easy way to verify this is to open your function in the Editor and press the F5 key. This would make the Editor try to run the file, and in case the file is not in path, it will prompt you with a message box. Choose Add to Path in that, and you must be fine to go.
One side note: at the end of the above process, Matlab command window will give an error saying arguments missing: obviously, we didn't provide any arguments when we tried to run from the editor. But from now on you can use the function from the command line giving the correct arguments.
The most common cause of this problem is that Matlab cannot find the file on it's search path. Basically, Matlab looks for files in:
The current directory (pwd);
Directly in a directory on the path (to see the path, type path at the command line)
In a directory named #(whatever the class of the first argument is) that is in any directory above.
As someone else suggested, you can use the command which, but that is often unhelpful in this case - it tells you Matlab can't find the file, which you knew already.
So the first thing to do is make sure the file is locatable on the path.
Next thing to do is make sure that the file that matlab is finding (use which) requires the same type as the first argument you are actually passing. I.el, If w is supposed to be different class, and there is a divrat function there, but w is actually empty, [], so matlab is looking for Double/divrat, when there is only a #(yourclass)/divrat. This is just speculation on my part, but this often bites me.
The function itself is valid matlab-code. The problem must be something else.
Try calling the function from within the directory it is located or add that directory to your searchpath using addpath('pathname').
The error code indicates the function definition cannot be found. Make sure you're calling the function from the same workspace as the divrat.m file is stored. And make sure divrat function is not a subfunction, it should be first function declaration in the file. You can also try to call the function from the same divrat.m file in order to see if the problem is with workspace selection or the function.
By the way, why didn't you simply say
s = sqrt(diag(C));
Wouldn't it be the same?
Also, name it divrat.m, not divrat.M. This shouldn't matter on most OSes, but who knows...
You can also test whether matlab can find a function by using the which command, i.e.
which divrat
I am pretty sure that the reason why this problem happened is because of the license of the toolbox (package) in which this function belongs in. Write which divrat and see what will be the result. If it returns path of the function and the comment Has no license available, then the problem is related to the license. That means, license of the package is not set correctly. Mostly it happens if the package (toolbox) of this function is added later, i.e., after installation of the original matlab. Please check and solve the license issue, then it will work fine.
I have been trying to use the pdg-dot plugin to help create a good graph of my software.The problem is different files don't have main so Frama-C complains. When I use the -main tag and specify a function to start it, it only creates a .dot file for the function and anything inside of it. Is there a way to make a .dot file of the entire .c file I have?
I don't think so. Each generated PDG represents one function only. But you can get the PDGs for all functions that are reachable from the entry point (main).
I was making a few changes in the dhcpagent command and on testing, it sort of fails. Now I know which function is being called in the end before dhcpagent exits. I want to trace the control from dhcpagent to that particular function lets say foo().I am looking for who called foo() and who called that function and so on, like a family tree, from dhcpagent to foo(). How do I do this ? I have very basic knowledge of dtrace, like how to construct a basic script, but no more. Could you suggest a script/resource from where I can learn and write the script myself ?
What I did try:
pid$target::functionname:entry //and the target was dhcpagent from the command line
Thanks
I think the following script can help you:
#!/usr/sbin/dtrace -Fs
pid$target:::entry,
pid$target:::return
{
}
In the above script, it can print how the function is called. But the output maybe awesome large!
If you only cared about dhcpagent module, I think the following script is a better choice:
#!/usr/sbin/dtrace -Fs
pid$target:dhcpagent::entry,
pid$target:dhcpagent::return
{
}
I am very new to C, so I apologize for this newby question.
I would like to use this source code in my project: http://base64.sourceforge.net/b64.c.
So, I include it in my test file:
#include <stdio.h>
#include "b64.c"
int main()
{
return 0;
}
However, main() is defined in b64.c as well, so upon compiling, I get:
test.c:4:5: error: redefinition of ‘main’
b64.c:495:5: note: previous definition of ‘main’ was here
test.c: In function ‘main’:
test.c:5:1: error: number of arguments doesn’t match prototype
b64.c:495:5: error: prototype declaration
What is the correct usage of this source file, or any? How do we correctly use it, or use functions defined in that file?
Edit: I understand that the problem is due to the duplicate definitions of main. I know there can only be one. My question is rather, won't every meaningful project need it's main method? Then why is there a main method defined in b64.c? Are we just supposed to delete this method from the source code? It seems odd that the source code doesn't just come ready to be included and used.
It is never a good idea to #include a C source file into your code. You can either copy the code from the other C source file into your code, or include the needed prototypes in your code and make a call to the functions, linking those after compiling them separately.
you should use one of the two main functions.
If you want a new main, write your main method in your file and remove it from the 'b64.c' file, if you want to use it from the 'b64.c' file remove your (empty) main.
If main is defined in b64.c either you cannot simply redefine it in your main source file.
What do you want is to use several functions from b64.c in your program. Delete the main function from it and create a header file where you protoype all of the functions in b64.c. After that, include this header file in your main program. Have a look at this short Wikipedia entry. It should give you an overview of the topic.
Besides this: It seems that you aren't very familar with C. Try out some tutorials and go on reading about C.
First of all, you must redeclare the .c file as a .h, and then you have to go through the source code and rename any duplicate methods or global variable names. The main method is the starting point of a program so there can only be one.
(Usualy you dont include .c files, only .h)
if you want the functions inside the "b64.c" you should delete the main function from "b54.c"!
A C application needs one main() function. Your file b64.c looks like a self-sufficient C program so you don't need your test.c. Just compile and run b64.c.
When you are including that source file you are getting 2 main() declaration which is incorrect. So you have redefined "main" in this case.
Including .c into another .c file doesn't make sense. C files compile to .obj files, which are linked by the linker into the executable code , so there is no need to include one .C file into another. Instead, you can make a .h file that lists the functions and include that .h file
I need to include a .h file to my project which will be supplied at the runtime. Since .h files are linked at linking time i am unable to include .h file. So i decided to write a dummy program which would create .h file and then i would call my actual program. Is there anyway to do this. Or any other solution is possible. I basically need to create a .h file before my program starts execution and need to link it up to my program.
i actually should take a file which is created by user, parse the file and then create a structure with the fields present in that file.for example if the file contains the following data:-
fno:int:4,fname:char:30,ftype:int:4
then i should create a structure like
struct somename
{
int fno;
char fname[30];
int ftype
};
Then i should be able to create instances of the structure created. This is what i like to do
dlopen is a solution. It allows to load dynamic library at runtime.
Compile your dummy program as a dynamic library.
Make use of dlopen on your .so
Call any function you need as if it has been linked by gcc (see dlsym).
What you can do is:
create .h file
fork
if in child: execve
if in father: wait (or not, depends on what you want to do)
I would use a Makefile; your program would receive the header file at runtime, (perhaps check it?) then execve() the make command passing the name of the file.
However, this sounds very cumbersome; perhaps you are trying to achieve something with the wrong tool. Maybe you want to use some scripting first? Or write two separate programs..? What are you trying to do?