- #1
cppIStough
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Title says it all, I'm trying to link FFTW and am getting a linker error. Anyone here have experience using this library?
Anyone with experience linking FFTW for C++
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- Thread starter cppIStough
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In summary, the discussion revolves around the challenges and solutions related to linking the FFTW library in C++ projects. Users share their experiences, troubleshooting tips, and best practices to ensure successful integration of FFTW for performing fast Fourier transforms, emphasizing the importance of proper compiler flags, library paths, and header file inclusions.
- #2
Vanadium 50
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All except the command you are using and the error message you get.cppIStough said:
- #3
cppIStough
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hahaha okay, fair enough, i just wanted to know if anyone had used it. Okay, so I'm using windows on visual studio. I configure the solution i'm currently trying to link with to include the path to the FFTW3.lib file: in order to do this I'm clicking properties > Linker > Input and then adding this directory in Additional Dependencies.Vanadium 50 said:
I also have this directory added to the VC++ Directories > Include Directories and Library Directories.
Then when I #include <fftw3.h> I receive the error:
Build started...
1>------ Build started: Project: signal.lib, Configuration: Release x64 ------
1>signal.lib.cpp
1>LINK : fatal error LNK1181: cannot open input file 'C:\external_libs\fftw-3.3.10\Release.obj'
1>Done building project "signal.lib.vcxproj" -- FAILED.
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
========== Build started at 4:57 PM and took 01.500 seconds ==========
But I am not sure why it is looking for a .obj file. Any help? Below is a snippet of the directory I'm pointing to, and no .obj file there
- #4
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I don't develop in Windows, but in unix, the command is different to link in foo.obj and foo.lib.
FAQ: Anyone with experience linking FFTW for C++
1. What is FFTW and why should I use it in my C++ project?
FFTW (Fastest Fourier Transform in the West) is a C library designed for computing the discrete Fourier transform (DFT) in one or more dimensions, and it is widely regarded for its performance and flexibility. You should consider using FFTW in your C++ project if you need efficient computation of Fourier transforms, especially for large datasets, as it can significantly speed up the processing time compared to naive algorithms.
2. How do I install FFTW for use in a C++ project?
To install FFTW, you can download the source code from the official FFTW website and compile it using a C compiler. Alternatively, many package managers (like apt for Ubuntu or Homebrew for macOS) provide precompiled binaries. After installation, ensure that the include and library paths are correctly set in your C++ project to link against the FFTW library.
3. How do I link FFTW in my C++ project?
To link FFTW in your C++ project, you need to specify the FFTW library in your build configuration. If you are using a Makefile, you can add `-lfftw3` to your linker flags. If you are using an IDE, you can typically add the library in the project settings under linker options. Make sure to also include the FFTW header files in your source code with `#include
4. What are the common errors when linking FFTW, and how can I troubleshoot them?
Common errors when linking FFTW include "undefined reference" errors, which usually indicate that the FFTW library is not correctly linked. To troubleshoot, ensure that the FFTW library is installed, the library path is included in your linker settings, and that you are linking against the correct version of the library (e.g., `libfftw3.a` or `libfftw3.so`). Additionally, check that you are using the correct compiler flags.
5. Can I use FFTW with C++ features like classes and templates?
Yes, you can use FFTW with C++ features such as classes and templates. FFTW is a C library, but you can create C++ wrapper classes around FFTW functions to encapsulate its functionality in a more object-oriented way. Just ensure that you manage the FFTW plans and memory allocation properly, as FFTW requires specific handling of its data structures.