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As an example, we\nplot these different windows.\n\n" }, { "__type": "Code", "__tag": 4050, "value": "import numpy as np\nfrom scipy.signal.windows import general_hamming\nfrom scipy.fft import fft, fftshift\nimport matplotlib.pyplot as plt\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\n" }, { "__type": "Code", "__tag": 4050, "value": "fig1, spatial_plot = plt.subplots()\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "spatial_plot.set_title(\"Generalized Hamming Windows\")\nspatial_plot.set_ylabel(\"Amplitude\")\nspatial_plot.set_xlabel(\"Sample\")\n", "execution_status": "failure" }, { "__type": "Text", "__tag": 4046, "value": "\n" }, { "__type": "Code", "__tag": 4050, "value": "fig2, freq_plot = plt.subplots()\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "freq_plot.set_title(\"Frequency Responses\")\nfreq_plot.set_ylabel(\"Normalized magnitude [dB]\")\nfreq_plot.set_xlabel(\"Normalized frequency [cycles per sample]\")\n", "execution_status": "failure" }, { "__type": "Text", "__tag": 4046, "value": "\n" }, { "__type": "Code", "__tag": 4050, "value": "for alpha in [0.75, 0.7, 0.52]:\n window = general_hamming(41, alpha)\n spatial_plot.plot(window, label=\"{:.2f}\".format(alpha))\n A = fft(window, 2048) / (len(window)/2.0)\n freq = np.linspace(-0.5, 0.5, len(A))\n response = 20 * np.log10(np.abs(fftshift(A / abs(A).max())))\n freq_plot.plot(freq, response, label=\"{:.2f}\".format(alpha))\nfreq_plot.legend(loc=\"upper right\")\nspatial_plot.legend(loc=\"upper right\")\n", "execution_status": "failure" } ], "title": [], "level": 0, "target": null }, "see_also": [ { "__type": "SeeAlsoItem", "__tag": 4028, "name": { "__type": "CrossRef", "__tag": 4002, "value": "hamming", "reference": { "__type": "RefInfo", "__tag": 4000, "module": "current-module", "version": "current-version", "kind": "to-resolve", "path": "hamming" }, "kind": "module" }, "descriptions": [], "type": "func" }, { "__type": "SeeAlsoItem", "__tag": 4028, "name": { "__type": "CrossRef", "__tag": 4002, "value": "hann", "reference": { "__type": "LocalRef", "__tag": 4022, "kind": "module", "path": "scipy.signal.windows._windows:hann" }, "kind": "module" }, "descriptions": [], "type": "func" } ], "signature": { "__type": "SignatureNode", "__tag": 4029, "kind": "function", "parameters": [ { "__type": "SigParam", "__tag": 4030, "name": "M", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "alpha", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "sym", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "True" }, { "__type": "SigParam", "__tag": 4030, "name": "xp", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "KEYWORD_ONLY", "default": "None" }, { "__type": "SigParam", "__tag": 4030, "name": "device", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "KEYWORD_ONLY", "default": "None" } ], "return_annotation": { "__type": "Empty", "__tag": 4031 }, "target_name": "general_hamming" }, "references": [ ".. [1] DSPRelated, \"Generalized Hamming Window Family\",", " https://www.dsprelated.com/freebooks/sasp/Generalized_Hamming_Window_Family.html", ".. [2] Wikipedia, \"Window function\",", " https://en.wikipedia.org/wiki/Window_function", ".. [3] Riccardo Piantanida ESA, \"Sentinel-1 Level 1 Detailed Algorithm", " Definition\",", " https://sentinel.esa.int/documents/247904/1877131/Sentinel-1-Level-1-Detailed-Algorithm-Definition", ".. [4] Matthieu Bourbigot ESA, \"Sentinel-1 Product Definition\",", " https://sentinel.esa.int/documents/247904/1877131/Sentinel-1-Product-Definition" ], "qa": "scipy.signal.windows._windows:general_hamming", "arbitrary": [], "local_refs": [ "M", "alpha", "device: any", "sym", "w", "xp" ] }