Eigen is located in the file
C:\Users\jherb_000\Downloads\eigen-eigen-07105f7124f9
I thought to include eigen you just use
`#include "C:\Users\jherb_000\Downloads\eigen-eigen-07105f7124f9\Eigen/Dense" `
But it is not compiling. I know it can work because I have done it before, and the eigen website does not explain how to do this unless you are using specific programs like g++.
Since you imply via the tags that you're using qt-creator, your problem boils down to "How do I add an include directory in qt-creator?" There are answers for that here, here and others. One thing to note is that the path you should add is C:\Users\jherb_000\Downloads\eigen-eigen-07105f7124f9.
What happens is when you include a specific file in a specific directory, if that file doesn't #include any other files (ok, other files that aren't in the include paths) all works well. But if it does, (and Eigen files include other file in the Eigen project) then the compiler does not know where to search for them. That's why you have to explicitly tell the compiler which directories to look for files that are included.
Very easy. Let's say you have a dependencies directory, and inside you have the eigen directory. In your .pro file, you could add your dependencies path to your INCLUDEPATH:
INCLUDEPATH += ../dependencies/ # or wherever that path is (relative to your .pro file)
Then, to include the Dense module, you do:
#include <eigen/Dense>
where eigen refers to your folder eigen in your dependencies folder. Many variations possible in function of your setup, but you got the idea.
Ok then what you need to do is:
Copy the C:\Users\jherb_000\Downloads\eigen-eigen-07105f7124f9\Eigen directory and all it's contents to wherever you're keeping all your third-party library files on your machine. (You probably wouldn't want to keep these files in your Downloads folder). For example let's say this directory is copied to C:\jacks_code\Eigen. Then,
Add this new directory to Qt-creator's list of directories to search (see Aki's answer for links):
In each of your source files, to include the Eigen templates, use the preprocessor directive:
#include <Dense>
The compiler will use the directories you told it, to dereference the file to C:\jacks_code\Eigen\Dense (the complete filename). It's a bit confusing here because the files in the root Eigen folder don't have .h or .c or .cpp or .hpp extensions.
Hope that helps. You can also read the INSTALL file in the base of the unzipped package.
Related
Sorry if my phrasing of the question is a bit confusing:
How do I set includes to be relative to the relativity of the source file from the root path?
I am trying to compile a C++ project (not my own), and there are two folders: src and include.
The .cpp source files are located in src and the header files are located in include.
I would like to compile all the source files.
However, the #includes in the source files are relative, as if the include folder tree and the src folder tree were merged.
For example src/foo/bar/baz.cpp might have #include "baz.h". In this scenario, the header file is supposed to be searched for in include/foo/bar/baz.h rather than include/baz.h.
How do I achieve this with GCC? I'm sure a similar question exists on the internet already, I just can't figure out how to phrase my question well.
Here is what I've tried so far which is incorrect:
gcc src/**/*.cpp -I include
Note: I still need to be able to append additional -I <folder> at the end of the command for including files the normal way.
There is no magic compiler option to do what you want.
Solution 1: Change the #include directives to be relative to the include directory.
Solution 2: Don't use separate directories and move the headers into src directory.
I'm trying to make a cross-platforms crypto library in C++ at https://github.com/haithngn/cryptor something like https://github.com/MailCore/mailcore2
The Structure is:
Can I make any header files can be include in the statements like this:
#include <Cryptor/MD5Encryptor.h>
I can include these header directly from absolutely file path
../core/CryptorCore.h
But these format will make the source code cannot build succeed in an XCode Project.
I tried to simulate the MailCore2 but that's very difficult.
Hope you can suggest me any solution or do a favor PR on my Repository.
Thanks,
You need to have a proper hierarchy. First, no, you can't have
#include <Cryptor/MD5Encryptor.h>
with your current setup, not while building the library, and not without flattening the hierarchy when installing your files (which CMake can do).
What you can do is:
#include <Cryptor/core/abstract/MD5Encryptor.h>
if you add your project inside a Cryptor folder instead of being at the root of your project.
I would advise you to create a Cryptor.cmake file that would allow people to pick up your library once installed, so that they don't have to know where the library includes are or what the libraries name is.
It should not be necessary to point to every single header file. Just add all directories containing these header files with include_directories(PATH_TO_HEADERS).
For the include of the header file src/core/CryptorCore.h with
#include "CryptorCore.h"
you have to point to
include_directories(${PROJECT_DIR}/core/)
I'm trying to build a Makefile with separate folder for my sources and my headers. I have a the root of my project that contain an include folder that holds my .hpp files, and a source folder that holds my .cpp files. How can i build the Makefile that it builds all the .cpp with the respective .hpp files ?
How to create the program output in a folder called build ?
Thank you in advance
Make is so diverse, there's a LOT of ways to do this, but the end result is -I<your hpp path> (or -J) needs to be passed to the compiler to tell it additional include paths to search when resolving #include
The path needs to relative to the invocation of the rule directory, or relative to the file (I'm pretty sure the compiler searches both).
A lot of makefiles use CPPOPTS and CCOPTS or some variant of that in the makefile to pass extra options to the C or CPP compiler. Try adding:
CPPOPTS += -I..\include
To your makefile (assuming you've segregated your source and include files that way).
Again, this is ALL dependent on your makefile.
I'm trying to build a Makefile with separate folder for my sources and my headers.
An alternative way would be to have your headers in the same directory as your .cpp files. And in that top level include folder you can put symbolic links to the headers.
Earlier I asked for help in including an external library called Eigen in xcode 4. I finally managed to get it to include the header file I wanted to use, Array, by going to build phases, link binary with libraries, and then adding the sub-folder within the Eigen archive where Array.h was located, Core. I also added the filepath to Core's parent directory, src, in header search paths.
When I finally managed to add the line of code #include <Core/Array.h> without it getting highlighted as an error, I ran the application (which worked previously) and XCode said that the build failed, with the error messages citing semantic issues. I checked the error message and they include, "Uknown identifier 'Array'" in a file named Array.h.
All of the header files are in src and according to the Eigen website, they are all that's needed to use Eigen with c++. I've attempted to reformat the binary links so they go to src instead of Core, and adjusting the buildpath to lead to the parent directory of src, ensuring that all header files can now be accessed, but I'm still getting semantics issues. Does anyone have a solution to this?
You generally want to include the Core file, not the individual .h files, i.e.
#include <Eigen/Core>
There are exceptions, but again, you won't be including the .h files, those are used internally. Additionally, it appears that your include path points to the ./Eigen/src/ directory. You want to move it up two directories so that when you write #include <Eigen/Core> it finds the Core file correctly. The files that you'll most likely include are the extension-less ones in the Eigen directory.
I'm using a library with an include structure where the .h files are all in a single directory. These .h files contains a single line, a #include directive which points to the 'real' header file in specific source folder locations. The #include path in these files is relative.
So, here's an example. The directory structure is:
/project
/sources
<my .cpp files>
<my .cpp files>
...
/include
/component
foo1.h
foo2.h
/platformA/something/foo1.h
/platformB/somethingelse/foo2.h
/include/component/foo1.h contains a single line of code:
#include "../platformA/something/foo1.h"
/include/component/foo2.h contains the single line of code #include "../platformB/somethingelse/foo2.h"
In my sources, I simply have:
#include "component/foo1.h"
The header search path for my project points to /include
Now, Xcode 4 is able to find component/foo1.h in /include, but it's unable to follow the relative include path within those headers and find the 'real' foo1.h in the `/platformA/something' directory, and so on.
I suspect it's because the include paths in the top-level foo1.h file is relative to its location, but Xcode might be treating it as relative to some other location (project root or something)? FWIW, Visual Studio has no problems with an identical configuration.
What can I do to remedy this?
From your directory structure it seems that the directories platformA and platformB are placed outside the include folder. There are two possible solutions to this:
Solution A
Move these
to include folder.
Solution B
Add project/platformA and
project/platformB to the
directories where include files
should be looked for in project
settings.
Don't use relative paths. Seriously, it's implementation-defined behavior how they work, so different compilers/environments/platforms will behave differently, and in your case, Xcode is almost certainly invoking GCC or clang in some sort of "build" directory, which may or may not be a sibling to your sources directory.
It's not worth the headache.
Put platformA and platformB in include, or add another directory (say, platform-include) put them in there, and add that directory to your include path.