{"id":18664542,"url":"https://github.com/lzhbrian/fast-fourier-transform","last_synced_at":"2025-04-11T21:32:50.156Z","repository":{"id":117429150,"uuid":"71771876","full_name":"lzhbrian/Fast-Fourier-Transform","owner":"lzhbrian","description":"A C++ Implementation of Fast Fourier Transform (Project of Digital Signal Processing course)","archived":false,"fork":false,"pushed_at":"2017-03-04T03:36:19.000Z","size":795,"stargazers_count":14,"open_issues_count":1,"forks_count":4,"subscribers_count":3,"default_branch":"master","last_synced_at":"2025-03-25T19:21:21.599Z","etag":null,"topics":["c-plus-plus","dft","fft"],"latest_commit_sha":null,"homepage":"","language":"TeX","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"apache-2.0","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/lzhbrian.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2016-10-24T09:13:12.000Z","updated_at":"2025-02-19T01:25:50.000Z","dependencies_parsed_at":null,"dependency_job_id":"ff9b09a0-c91b-42c3-8e72-c248c9ca0fb7","html_url":"https://github.com/lzhbrian/Fast-Fourier-Transform","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/lzhbrian%2FFast-Fourier-Transform","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/lzhbrian%2FFast-Fourier-Transform/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/lzhbrian%2FFast-Fourier-Transform/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/lzhbrian%2FFast-Fourier-Transform/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/lzhbrian","download_url":"https://codeload.github.com/lzhbrian/Fast-Fourier-Transform/tar.gz/refs/heads/master","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":248483367,"owners_count":21111435,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["c-plus-plus","dft","fft"],"created_at":"2024-11-07T08:23:57.582Z","updated_at":"2025-04-11T21:32:50.132Z","avatar_url":"https://github.com/lzhbrian.png","language":"TeX","funding_links":[],"categories":[],"sub_categories":[],"readme":"# Fast-Fourier-Transform\n\nAn Implementation of *__Fast Fourier Transform__*\n\n```\n├── LICENSE\n├── README.md\n├── src\n│   ├── complex.h\n│   ├── dft.h\n│   ├── dif_fft.h\n│   ├── dit_fft.h\n│   ├── fft\n│   ├── fft.cpp\n│   └── validate_n_evaluate.h\n└── tex\n```\n\n## Info:\n\n* Work by __Brian Lin, Tzu-Heng__\n  * W42, 2014011054\n  * Dept. of Electronic Engineering, Tsinghua University\n  * DSP Course Work\n\n\n* Decimate in Time/Frequency, Fast Fourier Transform\n  * __2-base DIT-FFT__, __2-base DIF-FFT__ \u0026 the __Original DFT__ method\n\n  * You can change the __`[input sequence]`__ in the __`main()`__ function of __`fft.cpp`__.\n\n  * Usage:\n\n    ```sh\n    make ./fft\n    ./fft [N_max] [validate_or_evaluate] [dft_dit_dif]\n    ```\n\n* There are two modes. \n  * __Mode 1__: Output the result of DFT *using three methods respectively*.\n  * __Mode 2__: Evaluate the performance of *three algorithms respectively*.\n\n\n\n\n## Usage:\n\n* __Mode 1: Output__\n  * To output result of __N=2^k__ point __DFT / DIT-FFT / DIF-FFT__:\n\n    ```sh\n    # DFT:\n    \t./fft 8 1 1\t# Calc a 8-point sequence\n    \t./fft 16 1 1\t# Calc a 16-point sequence\n    # DIT-FFT:\n    \t./fft 16 1 2\n    # DIF-FFT:\n    \t./fft 16 1 3\n    # All:\n    \t./fft 16 1 4\n    ```\n\n* __Mode 2: Evaluate Performance__\n  * To output the run time of __DFT / DIT-FFT / DIF-FFT__\n    * executing __N = 2^{ (10), (11), ..., (10+N_max-1) }__ respectively.\n\n    ```sh\n    # DFT:\n    \t./fft 4 0 1\t# Calc 2^{10~13}\n    \t./fft 6 0 1\t# Calc 2^{10~15}\n    \t./fft 7 0 1\t# Calc 2^{10~16}\n    # DIT-FFT:\n    \t./fft 7 0 2\n    # DIF-FFT:\n    \t./fft 7 0 3\n    # All:\n    \t./fft 7 0 4\n    ```\n\n\n\n## Output Result:\n\n* __Mode 1: Output__\n\n  * The result of command __`./fft 8 1 4`__ may look like this:\n\n    ```\n    Lin, Tzu-Heng's Work, 2014011054, W42\n    Dept. of Electronic Enigeering, Tsinghua University\n\n    Starting, This project is to calc DFT in Original-DFT / DIT-FFT / DIF-FFT...\n    \tFor Usage, Please see 'fft.cpp' \n\n    Calculating DFT...\n    \tX[0] = 2 + j*0\n    \tX[1] = 1.70711 + j*-0.707107\n    \tX[2] = 1 + j*-1\n    \tX[3] = 0.292893 + j*-0.707107\n    \tX[4] = 1.33227e-15 + j*-5.35898e-08\n    \tX[5] = 0.292893 + j*0.707107\n    \tX[6] = 1 + j*1\n    \tX[7] = 1.70711 + j*0.707107\n    Calculating DIT-FFT...\n    \tX[0] = 2 + j*0\n    \tX[1] = 1.70711 + j*-0.707107\n    \tX[2] = 1 + j*-1\n    \tX[3] = 0.292893 + j*-0.707107\n    \tX[4] = 0 + j*0\n    \tX[5] = 0.292893 + j*0.707107\n    \tX[6] = 1 + j*1\n    \tX[7] = 1.70711 + j*0.707107\n    Calculating DIF-FFT...\n    \tX[0] = 2 + j*0\n    \tX[1] = 1.70711 + j*-0.707107\n    \tX[2] = 1 + j*-1\n    \tX[3] = 0.292893 + j*-0.707107\n    \tX[4] = 0 + j*0\n    \tX[5] = 0.292893 + j*0.707107\n    \tX[6] = 1 + j*1\n    \tX[7] = 1.70711 + j*0.707107\n    ```\n\n* __Mode 2: Output__\n\n  * The result of command __`./fft 7 0 4`__ may look like this:\n\n    ```\n    Lin, Tzu-Heng's Work, 2014011054, W42\n    Dept. of Electronic Enigeering, Tsinghua University\n\n    This project is to calc DFT in Original-DFT / DIT-FFT / DIF-FFT...\n    \tFor Usage, Please see 'fft.cpp' \n\n    Calculating DIT-FFT...\n    N = 1024\tRun time = 2 ms\n    N = 2048\tRun time = 6 ms\n    N = 4096\tRun time = 14 ms\n    N = 8192\tRun time = 24 ms\n    N = 16384\tRun time = 53 ms\n    N = 32768\tRun time = 106 ms\n    N = 65536\tRun time = 200 ms\n    Calculating DIF-FFT...\n    N = 1024\tRun time = 1 ms\n    N = 2048\tRun time = 3 ms\n    N = 4096\tRun time = 7 ms\n    N = 8192\tRun time = 16 ms\n    N = 16384\tRun time = 39 ms\n    N = 32768\tRun time = 79 ms\n    N = 65536\tRun time = 154 ms\n    Calculating DFT...\n    N = 1024\tRun time = 38 ms\n    N = 2048\tRun time = 180 ms\n    N = 4096\tRun time = 771 ms\n    N = 8192\tRun time = 2948 ms\n    N = 16384\tRun time = 12811 ms\n    N = 32768\tRun time = 61836 ms\n    N = 65536\tRun time = 356046 ms\n    ```\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Flzhbrian%2Ffast-fourier-transform","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Flzhbrian%2Ffast-fourier-transform","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Flzhbrian%2Ffast-fourier-transform/lists"}