{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from matplotlib import pyplot\n",
    "from shapely.geometry import LineString\n",
    "\n",
    "%matplotlib inline"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "\n",
    "BLUE =   '#6699cc'\n",
    "YELLOW = '#ffcc33'\n",
    "GREEN =  '#339933'\n",
    "GRAY =   '#999999'\n",
    "\n",
    "def plot_coords(ax, ob):\n",
    "    x, y = ob.xy\n",
    "    ax.plot(x, y, 'o', color=GRAY, zorder=1)\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "\n",
    "fig = pyplot.figure(1, figsize=(12,20), dpi=90) #1, figsize=(10, 4), dpi=180)\n",
    "\n",
    "a = LineString([(0, 0), (1, 1), (1,2), (2,2)])\n",
    "b = LineString([(0, 0), (1, 1), (2,1), (2,2)])\n",
    "\n",
    "# 1: disconnected multilinestring\n",
    "ax = fig.add_subplot(121)\n",
    "\n",
    "plot_coords(ax, a)\n",
    "plot_coords(ax, b)\n",
    "\n",
    "x, y = a.xy\n",
    "ax.plot(x, y, color=YELLOW, alpha=0.5, linewidth=3, solid_capstyle='round', zorder=2)\n",
    "\n",
    "x, y = b.xy\n",
    "ax.plot(x, y, color=GREEN, alpha=0.5, linewidth=3, solid_capstyle='round', zorder=2)\n",
    "\n",
    "ax.set_title('a) lines')\n",
    "\n",
    "xrange = [-1, 3]\n",
    "yrange = [-1, 3]\n",
    "ax.set_xlim(*xrange)\n",
    "ax.set_xticks( [-1, 0, 1, 2, 3])\n",
    "ax.set_ylim(*yrange)\n",
    "ax.set_yticks( [-1, 0, 1, 2, 3])\n",
    "ax.set_aspect(1)\n",
    "\n",
    "#2: invalid self-touching ring\n",
    "ax = fig.add_subplot(122)\n",
    "\n",
    "x, y = a.xy\n",
    "ax.plot(x, y, color=GRAY, alpha=0.7, linewidth=1, solid_capstyle='round', zorder=1)\n",
    "x, y = b.xy\n",
    "ax.plot(x, y, color=GRAY, alpha=0.7, linewidth=1, solid_capstyle='round', zorder=1)\n",
    "\n",
    "for ob in a.intersection(b):\n",
    "    x, y = ob.xy\n",
    "    if len(x) == 1:\n",
    "        ax.plot(x, y, 'o', color=BLUE, zorder=2)\n",
    "    else:\n",
    "        ax.plot(x, y, color=BLUE, alpha=0.7, linewidth=3, solid_capstyle='round', zorder=2)\n",
    "\n",
    "ax.set_title('b) collection')\n",
    "\n",
    "xrange = [-1, 3]\n",
    "yrange = [-1, 3]\n",
    "ax.set_xlim(*xrange)\n",
    "ax.set_xticks([-1, 0, 1, 2, 3])\n",
    "ax.set_ylim(*yrange)\n",
    "ax.set_yticks([-1, 0, 1, 2, 3])\n",
    "ax.set_aspect(1)\n",
    "\n",
    "pyplot.show()\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
 ],
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