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First define the bin\nedges:\n\n" }, { "__type": "Code", "__tag": 4050, "value": "xedges = [0, 1, 3, 5]\nyedges = [0, 2, 3, 4, 6]\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\nNext we create a histogram H with random bin content:\n\n" }, { "__type": "Code", "__tag": 4050, "value": "x = np.random.normal(2, 1, 100)\ny = np.random.normal(1, 1, 100)\nH, xedges, yedges = np.histogram2d(x, y, bins=(xedges, yedges))\nH = H.T\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\n:func:`imshow ` can only display square bins:\n\n" }, { "__type": "Code", "__tag": 4050, "value": "fig = plt.figure(figsize=(7, 3))\nax = fig.add_subplot(131, title='imshow: square bins')\nplt.imshow(H, interpolation='nearest', origin='lower',\n extent=[xedges[0], xedges[-1], yedges[0], yedges[-1]])\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\n:func:`pcolormesh ` can display actual edges:\n\n" }, { "__type": "Code", "__tag": 4050, "value": "ax = fig.add_subplot(132, title='pcolormesh: actual edges',\n aspect='equal')\nX, Y = np.meshgrid(xedges, yedges)\nax.pcolormesh(X, Y, H)\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\n:class:`NonUniformImage ` can be used to\ndisplay actual bin edges with interpolation:\n\n" }, { "__type": "Code", "__tag": 4050, "value": "ax = fig.add_subplot(133, title='NonUniformImage: interpolated',\n aspect='equal', xlim=xedges[[0, -1]], ylim=yedges[[0, -1]])\nim = NonUniformImage(ax, interpolation='bilinear')\nxcenters = (xedges[:-1] + xedges[1:]) / 2\nycenters = (yedges[:-1] + yedges[1:]) / 2\nim.set_data(xcenters, ycenters, H)\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "ax.add_image(im)\n", "execution_status": "failure" }, { "__type": "Code", "__tag": 4050, "value": "plt.show()\n", "execution_status": "success" }, { "__type": "Figure", "__tag": 4024, "value": { "__type": "RefInfo", "__tag": 4000, "module": "numpy", "version": "2.4.4", "kind": "assets", "path": "fig-bbfba3d8ef190340.png" } }, { "__type": "Text", "__tag": 4046, "value": "\nIt is also possible to construct a 2-D histogram without specifying bin\nedges:\n\n" }, { "__type": "Code", "__tag": 4050, "value": "n = 10000\nx = np.linspace(1, 100, n)\ny = 2*np.log(x) + np.random.rand(n) - 0.5\nH, yedges, xedges = np.histogram2d(y, x, bins=20)\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\nNow we can plot the histogram using\n:func:`pcolormesh `, and a\n:func:`hexbin ` for comparison.\n\n" }, { "__type": "Code", "__tag": 4050, "value": "fig, (ax1, ax2) = plt.subplots(ncols=2, sharey=True)\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "ax1.pcolormesh(xedges, yedges, H, cmap='rainbow')\nax1.plot(x, 2*np.log(x), 'k-')\nax1.set_xlim(x.min(), x.max())\nax1.set_ylim(y.min(), y.max())\nax1.set_xlabel('x')\nax1.set_ylabel('y')\nax1.set_title('histogram2d')\n", "execution_status": "failure" }, { "__type": "Code", "__tag": 4050, "value": "ax1.grid()\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\n" }, { "__type": "Code", "__tag": 4050, "value": "ax2.hexbin(x, y, gridsize=20, cmap='rainbow')\nax2.plot(x, 2*np.log(x), 'k-')\nax2.set_title('hexbin')\nax2.set_xlim(x.min(), x.max())\nax2.set_xlabel('x')\n", "execution_status": "failure" }, { "__type": "Code", "__tag": 4050, "value": "ax2.grid()\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\n" }, { "__type": "Code", "__tag": 4050, "value": "plt.show()\n", "execution_status": "success" }, { "__type": "Figure", "__tag": 4024, "value": { "__type": "RefInfo", "__tag": 4000, "module": "numpy", "version": "2.4.4", "kind": "assets", "path": "fig-bf0eaf0838ef3826.png" } } ], "title": [], "level": 0, "target": null }, "see_also": [ { "__type": "SeeAlsoItem", "__tag": 4028, "name": { "__type": "CrossRef", "__tag": 4002, "value": "histogram", "reference": { "__type": "LocalRef", "__tag": 4022, "kind": "module", "path": "numpy:histogram2d" }, "kind": "module" }, "descriptions": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "1D histogram" } ] } ], "type": null }, { "__type": "SeeAlsoItem", "__tag": 4028, "name": { "__type": "CrossRef", "__tag": 4002, "value": "histogramdd", "reference": { "__type": "RefInfo", "__tag": 4000, "module": "current-module", "version": "current-version", "kind": "to-resolve", "path": "histogramdd" }, "kind": "module" }, "descriptions": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Multidimensional histogram" } ] } ], "type": null } ], "signature": { "__type": "SignatureNode", "__tag": 4029, "kind": "function", "parameters": [ { "__type": "SigParam", "__tag": 4030, "name": "x", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "y", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "bins", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "10" }, { "__type": "SigParam", "__tag": 4030, "name": "range", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "None" }, { "__type": "SigParam", "__tag": 4030, "name": "density", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "None" }, { "__type": "SigParam", "__tag": 4030, "name": "weights", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "None" } ], "return_annotation": { "__type": "Empty", "__tag": 4031 }, "target_name": "histogram2d" }, "references": null, "qa": "numpy:histogram2d", "arbitrary": [], "local_refs": [ "H", "bins", "density", "range", "weights", "x", "xedges", "y", "yedges" ] }