mirror of
https://github.com/rasbt/python_reference.git
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873 lines
47 KiB
Plaintext
873 lines
47 KiB
Plaintext
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{
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"metadata": {
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"name": "",
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"signature": "sha256:68e419b336c43b3a5f99d948a5148ad6a7da83f9796fdc45c9132c236a5a43bc"
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},
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"nbformat": 3,
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"nbformat_minor": 0,
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"worksheets": [
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{
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"cells": [
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"[Sebastian Raschka](http://sebastianraschka.com) \n",
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"\n",
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"- [Open in IPython nbviewer](http://nbviewer.ipython.org/github/rasbt/python_reference/blob/master/tutorials/awesome_things_ipynb?create=1) \n",
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"\n",
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"- [Link to this IPython notebook on Github](https://github.com/rasbt/python_reference/blob/master/tutorials/awesome_things_ipynb.ipynb) \n",
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"\n",
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"- [Link to the GitHub Repository python_reference](https://github.com/rasbt/python_reference/)"
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]
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"import time\n",
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"import platform\n",
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"print('Last updated: %s' %time.strftime('%d/%m/%Y'))\n",
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"print('Created using Python', platform.python_version())"
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],
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"language": "python",
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"metadata": {},
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"outputs": [
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"Last updated: 27/06/2014\n",
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"Created using Python 3.4.1\n"
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]
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}
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],
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"prompt_number": 37
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"<hr>\n",
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"I would be happy to hear your comments and suggestions. \n",
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"Please feel free to drop me a note via\n",
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"[twitter](https://twitter.com/rasbt), [email](mailto:bluewoodtree@gmail.com), or [google+](https://plus.google.com/+SebastianRaschka).\n",
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"<hr>"
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]
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},
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{
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"cell_type": "heading",
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"level": 1,
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"metadata": {},
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"source": [
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"Awesome things that you can do in IPython Notebooks (in progress)"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"<br>\n",
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"<br>"
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]
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},
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{
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"cell_type": "heading",
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"level": 2,
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"metadata": {},
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"source": [
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"Writing local files"
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]
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"%%file hello.py\n",
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"def func_inside_script(x, y):\n",
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" return x + y\n",
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"print('Hello World')"
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],
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"language": "python",
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"metadata": {},
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"outputs": [
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"Writing hello.py\n"
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]
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}
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],
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"prompt_number": 13
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"<br>\n",
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"<br>"
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]
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},
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{
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"cell_type": "heading",
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"level": 2,
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"metadata": {},
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"source": [
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"Running Python scripts"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"We can run Python scripts in IPython via the %run magic command. For example, the Python script that we created in the [Writing local files](#Writing-local-files) section."
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]
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"%run hello.py"
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],
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"language": "python",
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"metadata": {},
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"outputs": [
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"Hello World\n"
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]
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}
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],
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"prompt_number": 14
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"func_inside_script(1, 2)"
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],
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"language": "python",
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"metadata": {},
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"outputs": [
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{
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"metadata": {},
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"output_type": "pyout",
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"prompt_number": 16,
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"text": [
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"3"
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]
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}
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],
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"prompt_number": 16
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"<br>\n",
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"<br>"
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]
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},
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{
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"cell_type": "heading",
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"level": 2,
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"metadata": {},
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"source": [
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"Benchmarking"
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]
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"%timeit [x**2 for x in range(100)] "
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],
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"language": "python",
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"metadata": {},
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"outputs": [
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"10000 loops, best of 3: 38.8 \u00b5s per loop\n"
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]
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}
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],
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"prompt_number": 4
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"%timeit -r 5 -n 100 [x**2 for x in range(100)] "
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],
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"language": "python",
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"metadata": {},
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"outputs": [
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"100 loops, best of 5: 39 \u00b5s per loop\n"
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]
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}
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],
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"prompt_number": 3
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"<br>\n",
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"<br>"
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]
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},
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{
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"cell_type": "heading",
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"level": 2,
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"metadata": {},
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"source": [
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"Using system shell commands"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"By prepending a \"`!`\" we can conveniently execute most of the system shell commands, below are just a few examples."
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]
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"my_dir = 'new_dir'\n",
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"!mkdir $my_dir\n",
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"!pwd\n",
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"!touch $my_dir'/some.txt'\n",
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"!ls -l './new_dir'\n",
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"!ls -l $my_dir | wc -l"
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],
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"language": "python",
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"metadata": {},
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"outputs": [
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"/Users/sebastian/Desktop\r\n"
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]
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},
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"total 0\r\n",
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"-rw-r--r-- 1 sebastian staff 0 Jun 27 10:11 some.txt\r\n"
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]
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},
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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" 2\r\n"
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]
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}
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],
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"prompt_number": 12
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"<br>\n",
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"<br>"
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]
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},
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{
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"cell_type": "heading",
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"level": 2,
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"metadata": {},
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"source": [
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"Debugging"
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]
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"%debug \n",
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"def some_func():\n",
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" var = 'hello world'\n",
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" for i in range(5):\n",
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" print(i)\n",
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" i / 0\n",
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" return 'finished'"
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],
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"language": "python",
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"metadata": {},
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"outputs": [
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"> \u001b[0;32m<ipython-input-1-3d5f00f75cf4>\u001b[0m(5)\u001b[0;36msome_func\u001b[0;34m()\u001b[0m\n",
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"\u001b[0;32m 4 \u001b[0;31m \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mi\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
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"\u001b[0m\u001b[0;32m----> 5 \u001b[0;31m \u001b[0mi\u001b[0m \u001b[0;34m/\u001b[0m \u001b[0;36m0\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
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"\u001b[0m\u001b[0;32m 6 \u001b[0;31m \u001b[0;32mreturn\u001b[0m \u001b[0;34m'finished'\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
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"\u001b[0m\n"
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]
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},
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{
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"name": "stdout",
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"ipdb> var\n"
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]
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},
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{
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"output_type": "stream",
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"stream": "stdout",
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"text": [
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"'hello world'\n"
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]
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}
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"<br>\n",
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"<br>"
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]
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},
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{
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"cell_type": "heading",
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"level": 2,
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"metadata": {},
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"source": [
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"Inline Plotting with matplotlib"
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]
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"%matplotlib inline"
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],
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"language": "python",
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"metadata": {},
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"outputs": [],
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"prompt_number": 33
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},
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{
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"cell_type": "code",
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"collapsed": false,
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"input": [
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"import numpy as np\n",
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"from matplotlib import pyplot as plt\n",
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"import math\n",
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"\n",
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"def pdf(x, mu=0, sigma=1):\n",
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" \"\"\"Calculates the normal distribution's probability density \n",
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" function (PDF). \n",
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" \n",
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" \"\"\"\n",
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" term1 = 1.0 / ( math.sqrt(2*np.pi) * sigma )\n",
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" term2 = np.exp( -0.5 * ( (x-mu)/sigma )**2 )\n",
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" return term1 * term2\n",
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"\n",
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"\n",
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"x = np.arange(0, 100, 0.05)\n",
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"\n",
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"pdf1 = pdf(x, mu=5, sigma=2.5**0.5)\n",
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"pdf2 = pdf(x, mu=10, sigma=6**0.5)\n",
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"\n",
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"plt.plot(x, pdf1)\n",
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"plt.plot(x, pdf2)\n",
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"plt.title('Probability Density Functions')\n",
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"plt.ylabel('p(x)')\n",
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"plt.xlabel('random variable x')\n",
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"plt.legend(['pdf1 ~ N($\\mu=5$, $\\sigma=2.5$)', 'pdf2 ~ N($\\mu=10$, $\\sigma=6$)'], loc='upper right')\n",
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"plt.ylim([0,0.5])\n",
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"plt.xlim([0,20])\n",
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"\n",
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"plt.show()"
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],
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"language": "python",
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||
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"metadata": {},
|
||
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"outputs": [
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{
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||
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"metadata": {},
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||
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"output_type": "display_data",
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||
|
"png": "iVBORw0KGgoAAAANSUhEUgAAAYQAAAEZCAYAAACXRVJOAAAABHNCSVQICAgIfAhkiAAAAAlwSFlz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\ntWqa+Zo1a8amTZuMFUPkI1eu
|
||
|
"text": [
|
||
|
"<matplotlib.figure.Figure at 0x107e67080>"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 36
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "markdown",
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"<br>\n",
|
||
|
"<br>"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "heading",
|
||
|
"level": 2,
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"C-extensions via the Cython magic"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "markdown",
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"Cython (see [Cython's C-extensions for Python](http://cython.org)) is basically a hybrid between C and Python and can be pictured as compiled Python code with type declarations.\n",
|
||
|
"Since we are working in an IPython notebook here, we can make use of the very convenient IPython magic: It will take care of the conversion to C code, the compilation, and eventually the loading of the function.\n",
|
||
|
"Also, we are adding C type declarations; those type declarations are not necessary for using Cython, however, it will improve the performance of our code significantly."
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%load_ext cythonmagic"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [],
|
||
|
"prompt_number": 29
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%%cython\n",
|
||
|
"import numpy as np\n",
|
||
|
"cimport numpy as np\n",
|
||
|
"cimport cython\n",
|
||
|
"@cython.boundscheck(False) \n",
|
||
|
"@cython.wraparound(False)\n",
|
||
|
"@cython.cdivision(True)\n",
|
||
|
"cpdef cython_lstsqr(x_ary, y_ary):\n",
|
||
|
" \"\"\" Computes the least-squares solution to a linear matrix equation. \"\"\"\n",
|
||
|
" cdef double x_avg, y_avg, var_x, cov_xy,\\\n",
|
||
|
" slope, y_interc, temp\n",
|
||
|
" cdef double[:] x = x_ary # memoryview\n",
|
||
|
" cdef double[:] y = y_ary\n",
|
||
|
" cdef unsigned long N, i\n",
|
||
|
" \n",
|
||
|
" N = x.shape[0]\n",
|
||
|
" x_avg = 0\n",
|
||
|
" y_avg = 0\n",
|
||
|
" for i in range(N):\n",
|
||
|
" x_avg += x[i]\n",
|
||
|
" y_avg += y[i]\n",
|
||
|
" x_avg = x_avg/N\n",
|
||
|
" y_avg = y_avg/N\n",
|
||
|
" var_x = 0\n",
|
||
|
" cov_xy = 0\n",
|
||
|
" for i in range(N):\n",
|
||
|
" temp = (x[i] - x_avg)\n",
|
||
|
" var_x += temp**2\n",
|
||
|
" cov_xy += temp*(y[i] - y_avg)\n",
|
||
|
" slope = cov_xy / var_x\n",
|
||
|
" y_interc = y_avg - slope*x_avg\n",
|
||
|
" return (slope, y_interc)"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"building '_cython_magic_cf6c91cb1e11de8d2dbe7d9178e469df' extension\n"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"C compiler: /usr/bin/clang -fno-strict-aliasing -Werror=declaration-after-statement -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -I/Users/sebastian/miniconda3/envs/py34/include -arch x86_64\n",
|
||
|
"\n"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"compile options: '-I/Users/sebastian/miniconda3/envs/py34/lib/python3.4/site-packages/numpy/core/include -I/Users/sebastian/miniconda3/envs/py34/include/python3.4m -c'\n"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"clang: /Users/sebastian/.ipython/cython/_cython_magic_cf6c91cb1e11de8d2dbe7d9178e469df.c\n"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"/usr/bin/clang -bundle -undefined dynamic_lookup -L/Users/sebastian/miniconda3/envs/py34/lib -arch x86_64 /Users/sebastian/.ipython/cython/Users/sebastian/.ipython/cython/_cython_magic_cf6c91cb1e11de8d2dbe7d9178e469df.o -L/Users/sebastian/miniconda3/envs/py34/lib -o /Users/sebastian/.ipython/cython/_cython_magic_cf6c91cb1e11de8d2dbe7d9178e469df.so\n"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 30
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"import numpy as np\n",
|
||
|
"\n",
|
||
|
"x_ary = np.array([x_i*np.random.randint(8,12)/10 for x_i in range(100)])\n",
|
||
|
"y_ary = np.array([y_i*np.random.randint(10,14)/10 for y_i in range(100)])"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [],
|
||
|
"prompt_number": 31
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"cython_lstsqr(x_ary, y_ary)"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"metadata": {},
|
||
|
"output_type": "pyout",
|
||
|
"prompt_number": 32,
|
||
|
"text": [
|
||
|
"(1.1399825800539194, 2.0824398156005444)"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 32
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "markdown",
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"<br>\n",
|
||
|
"<br>"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "heading",
|
||
|
"level": 2,
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"Running Fortran Code"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "markdown",
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"There is also a convenient IPython magic command for compiling Fortran code. The Fortran magic uses NumPy's [F2PY](http://www.f2py.com) module for compiling and running the Fortran code. For more information, please see the ['Fortran magic's documentation'](http://nbviewer.ipython.org/github/mgaitan/fortran_magic/blob/master/documentation.ipynb)."
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%install_ext https://raw.github.com/mgaitan/fortran_magic/master/fortranmagic.py"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"Installed fortranmagic.py. To use it, type:\n",
|
||
|
" %load_ext fortranmagic\n"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 17
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%load_ext fortranmagic"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"javascript": [
|
||
|
"$.getScript(\"https://raw.github.com/marijnh/CodeMirror/master/mode/fortran/fortran.js\", function () {\n",
|
||
|
"IPython.config.cell_magic_highlight['magic_fortran'] = {'reg':[/^%%fortran/]};});\n"
|
||
|
],
|
||
|
"metadata": {},
|
||
|
"output_type": "display_data"
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 18
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%%fortran\n",
|
||
|
"SUBROUTINE fortran_lstsqr(ary_x, ary_y, slope, y_interc)\n",
|
||
|
" ! Computes the least-squares solution to a linear matrix equation. \"\"\"\n",
|
||
|
" IMPLICIT NONE\n",
|
||
|
" REAL(8), INTENT(in), DIMENSION(:) :: ary_x, ary_y\n",
|
||
|
" REAL(8), INTENT(out) :: slope, y_interc\n",
|
||
|
" REAL(8) :: x_avg, y_avg, var_x, cov_xy, temp\n",
|
||
|
" INTEGER(8) :: N, i\n",
|
||
|
" \n",
|
||
|
" N = SIZE(ary_x)\n",
|
||
|
"\n",
|
||
|
" x_avg = SUM(ary_x) / N\n",
|
||
|
" y_avg = SUM(ary_y) / N\n",
|
||
|
" var_x = 0\n",
|
||
|
" cov_xy = 0\n",
|
||
|
" \n",
|
||
|
" DO i = 1, N\n",
|
||
|
" temp = ary_x(i) - x_avg\n",
|
||
|
" var_x = var_x + temp**2\n",
|
||
|
" cov_xy = cov_xy + (temp*(ary_y(i) - y_avg))\n",
|
||
|
" END DO\n",
|
||
|
" \n",
|
||
|
" slope = cov_xy / var_x\n",
|
||
|
" y_interc = y_avg - slope*x_avg\n",
|
||
|
"\n",
|
||
|
"END SUBROUTINE fortran_lstsqr"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"\tBuilding module \"_fortran_magic_a044885f2b0c0feac78a230b6b714e2b\"...\n",
|
||
|
"\t\tConstructing wrapper function \"fortran_lstsqr\"...\n",
|
||
|
"\t\t slope,y_interc = fortran_lstsqr(ary_x,ary_y)\n",
|
||
|
"\tWrote C/API module \"_fortran_magic_a044885f2b0c0feac78a230b6b714e2b\" to file \"/var/folders/bq/_946cdn92t7bqzz5frpfpw7r0000gp/T/tmp3y_jxtl_/src.macosx-10.5-x86_64-3.4/_fortran_magic_a044885f2b0c0feac78a230b6b714e2bmodule.c\"\n",
|
||
|
"\tFortran 77 wrappers are saved to \"/var/folders/bq/_946cdn92t7bqzz5frpfpw7r0000gp/T/tmp3y_jxtl_/src.macosx-10.5-x86_64-3.4/_fortran_magic_a044885f2b0c0feac78a230b6b714e2b-f2pywrappers.f\"\n"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 22
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"import numpy as np\n",
|
||
|
"\n",
|
||
|
"x_ary = np.array([x_i*np.random.randint(8,12)/10 for x_i in range(100)])\n",
|
||
|
"y_ary = np.array([y_i*np.random.randint(10,14)/10 for y_i in range(100)])"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [],
|
||
|
"prompt_number": 23
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"fortran_lstsqr(x_ary, y_ary)"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"metadata": {},
|
||
|
"output_type": "pyout",
|
||
|
"prompt_number": 25,
|
||
|
"text": [
|
||
|
"(1.1313508052697814, 3.681685640167956)"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 25
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "markdown",
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"<br>\n",
|
||
|
"<br>"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "heading",
|
||
|
"level": 2,
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"Running code from other interpreters: Ruby, Perl, and Bash"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "markdown",
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"To use any interpreter that is installed on your system:"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%%script perl\n",
|
||
|
"print 'Hello, World!';"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"Hello, World!"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 44
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "markdown",
|
||
|
"metadata": {},
|
||
|
"source": [
|
||
|
"Or use the magic command for the respective interpreter directly:"
|
||
|
]
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%%perl\n",
|
||
|
"print 'Hello, World!';"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"Hello, World!"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 45
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%%ruby\n",
|
||
|
"puts \"Hello, World!\""
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"Hello, World!\n"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 46
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%%bash\n",
|
||
|
"echo \"Hello World!\""
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"Hello World!\n"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 47
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [
|
||
|
"%%script R --no-save\n",
|
||
|
"cat(\"Goodbye, World!\\n\")"
|
||
|
],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": [
|
||
|
{
|
||
|
"output_type": "stream",
|
||
|
"stream": "stdout",
|
||
|
"text": [
|
||
|
"\n",
|
||
|
"R version 3.0.2 (2013-09-25) -- \"Frisbee Sailing\"\n",
|
||
|
"Copyright (C) 2013 The R Foundation for Statistical Computing\n",
|
||
|
"Platform: x86_64-apple-darwin10.8.0 (64-bit)\n",
|
||
|
"\n",
|
||
|
"R is free software and comes with ABSOLUTELY NO WARRANTY.\n",
|
||
|
"You are welcome to redistribute it under certain conditions.\n",
|
||
|
"Type 'license()' or 'licence()' for distribution details.\n",
|
||
|
"\n",
|
||
|
" Natural language support but running in an English locale\n",
|
||
|
"\n",
|
||
|
"R is a collaborative project with many contributors.\n",
|
||
|
"Type 'contributors()' for more information and\n",
|
||
|
"'citation()' on how to cite R or R packages in publications.\n",
|
||
|
"\n",
|
||
|
"Type 'demo()' for some demos, 'help()' for on-line help, or\n",
|
||
|
"'help.start()' for an HTML browser interface to help.\n",
|
||
|
"Type 'q()' to quit R.\n",
|
||
|
"\n",
|
||
|
"> cat(\"Goodbye, World!\\n\")\n",
|
||
|
"Goodbye, World!\n",
|
||
|
"> \n"
|
||
|
]
|
||
|
}
|
||
|
],
|
||
|
"prompt_number": 55
|
||
|
},
|
||
|
{
|
||
|
"cell_type": "code",
|
||
|
"collapsed": false,
|
||
|
"input": [],
|
||
|
"language": "python",
|
||
|
"metadata": {},
|
||
|
"outputs": []
|
||
|
}
|
||
|
],
|
||
|
"metadata": {}
|
||
|
}
|
||
|
]
|
||
|
}
|