[Sample PR] Black Colormap

contrib_colormaps/colormaps/black.csv

@@ -0,0 +1,19 @@
+0, 0, 0.1
+0.047058823529411764,0.00784313725490196,0.058823529411764705
+0.09803921568627451,0.09803921568627451,0.4392156862745098
+0.4117647058823529,0.4117647058823529,0.4117647058823529
+0.3254901960784314,0.36470588235294116,0.3137254901960784
+0.28627450980392155,0.23137254901960785,0.23137254901960785
+0.3333333333333333,0.3333333333333333,0.3333333333333333
+0.21176470588235294,0.27058823529411763,0.30980392156862746
+0.25098039215686274,0.2901960784313726,0.2980392156862745
+0.29411764705882354,0.21176470588235294,0.12941176470588237
+0.23921568627450981,0.047058823529411764,0.00784313725490196
+0.23137254901960785,0.23529411764705882,0.21176470588235294
+0.20784313725490197,0.2196078431372549,0.2235294117647059
+0.20392156862745098,0.20392156862745098,0.20392156862745098
+0.1450980392156863,0.20784313725490197,0.1607843137254902
+0.1411764705882353,0.12941176470588237,0.1411764705882353
+0.13725490196078433,0.16862745098039217,0.16862745098039217
+0.10588235294117647,0.10588235294117647,0.10588235294117647
+0.10196078431372549,0.06666666666666667,0.06274509803921569

examples/colormaps/black.ipynb

@@ -0,0 +1,127 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Black"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "This colormap is constructed from [shades of black](https://en.wikipedia.org/wiki/Shades_of_black). It is meant to be used for qualitative data in an application where a dark colormap is appropriate.\n",
+    "\n",
+    "This colormap __is not__:\n",
+    "* colorblind friendly\n",
+    "* perceptually uniform"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from contrib_colormaps.plotting import swatch\n",
+    "import holoviews as hv\n",
+    "hv.extension('bokeh', 'matplotlib', logo=False)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%matplotlib inline\n",
+    "hv.render(swatch('black'), backend='matplotlib')"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from bokeh.plotting import show\n",
+    "show(hv.render(swatch('black'), backend='bokeh'))"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import numpy as np\n",
+    "\n",
+    "import contrib_colormaps as cc\n",
+    "\n",
+    "N = len(cc.black)\n",
+    "data = np.vstack([np.roll(np.arange(N), -i) for i in range(N)])\n",
+    "dbox = np.vstack([np.hstack([data, np.flip(data, axis=1)]),\n",
+    "                np.hstack([np.flip(data, axis=0), np.flip(data, axis=[0,1])])])"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import matplotlib.pyplot as plt\n",
+    "import matplotlib.colors as mcolors\n",
+    "\n",
+    "fig, ax = plt.subplots(figsize=(9,9))\n",
+    "ax.imshow(dbox, cmap=cc.m_black)\n",
+    "ax.axis('off')\n",
+    "ax.set_aspect('equal')\n",
+    "plt.show()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from bokeh.plotting import figure, show, output_notebook\n",
+    "\n",
+    "output_notebook()\n",
+    "p = figure()\n",
+    "p.image([dbox], x=0, y=0, dw=1, dh=1, palette=cc.b_black)\n",
+    "show(p)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.7.4"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}