{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Convergence of the Secant Method\n",
    "\n",
    "Copyright (C) 2020 Andreas Kloeckner\n",
    "\n",
    "<details>\n",
    "<summary>MIT License</summary>\n",
    "Permission is hereby granted, free of charge, to any person obtaining a copy\n",
    "of this software and associated documentation files (the \"Software\"), to deal\n",
    "in the Software without restriction, including without limitation the rights\n",
    "to use, copy, modify, merge, publish, distribute, sublicense, and/or sell\n",
    "copies of the Software, and to permit persons to whom the Software is\n",
    "furnished to do so, subject to the following conditions:\n",
    "\n",
    "The above copyright notice and this permission notice shall be included in\n",
    "all copies or substantial portions of the Software.\n",
    "\n",
    "THE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\n",
    "IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\n",
    "FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\n",
    "AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\n",
    "LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\n",
    "OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN\n",
    "THE SOFTWARE.\n",
    "</details>"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [],
   "source": [
    "import numpy as np\n",
    "import matplotlib.pyplot as pt"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [],
   "source": [
    "def f(x):\n",
    "    return np.exp(x) - 2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[<matplotlib.lines.Line2D at 0x7fca94ed4048>]"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    },
    {
     "data": {
      "image/png": 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\n",
      "text/plain": [
       "<Figure size 432x288 with 1 Axes>"
      ]
     },
     "metadata": {
      "needs_background": "light"
     },
     "output_type": "display_data"
    }
   ],
   "source": [
    "xgrid = np.linspace(-2, 3, 1000)\n",
    "pt.grid()\n",
    "pt.plot(xgrid, f(xgrid))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "What's the true solution of $f(x)=0$?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0.6931471805599453\n",
      "0.0\n"
     ]
    }
   ],
   "source": [
    "#clear\n",
    "xtrue = np.log(2)\n",
    "print(xtrue)\n",
    "print(f(xtrue))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Now let's run the secant method and keep track of the errors:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [],
   "source": [
    "errors = []\n",
    "x = 2\n",
    "xbefore = 3"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "At each iteration, print the current guess and the error."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "nan\n",
      "nan\n"
     ]
    },
    {
     "name": "stderr",
     "output_type": "stream",
     "text": [
      "/home/andreas/src/env-3.7/lib/python3.7/site-packages/ipykernel_launcher.py:2: RuntimeWarning: invalid value encountered in double_scalars\n",
      "  \n"
     ]
    }
   ],
   "source": [
    "#clear\n",
    "slope = (f(x)-f(xbefore))/(x-xbefore)\n",
    "\n",
    "xbefore = x\n",
    "x = x - f(x)/slope\n",
    "print(x)\n",
    "errors.append(abs(x-xtrue))\n",
    "print(errors[-1])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0.8824000774932711\n",
      "0.411823511031029\n",
      "0.14748204487642924\n",
      "0.027685962340313952\n",
      "0.0019826842906380815\n",
      "2.731067240058227e-05\n",
      "2.706515089823114e-08\n",
      "3.695932448977146e-13\n",
      "1.1102230246251565e-16\n",
      "1.1102230246251565e-16\n",
      "nan\n"
     ]
    }
   ],
   "source": [
    "for err in errors:\n",
    "    print(err)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "* Do you have a hypothesis about the order of convergence?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [],
   "source": [
    "#clear\n",
    "# Does not quite double the number of digits each round--unclear."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "------------\n",
    "Let's check:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0.5042249099646489\n",
      "0.6196358421422753\n",
      "0.6126884285565872\n",
      "0.6571696439293109\n",
      "0.6447273943575542\n",
      "0.6552765724242319\n",
      "0.6487597717813403\n",
      "14482.140529886734\n",
      "7243300082.988035\n",
      "nan\n"
     ]
    }
   ],
   "source": [
    "#clear\n",
    "for i in range(len(errors)-1):\n",
    "    print(errors[i+1]/errors[i]**1.618)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
 ],
 "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": "3.8.3"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 4
}