branch-loop-sequence.ipynb

{
 "metadata": {
  "name": "branch-loop-sequence"
 },
 "nbformat": 3,
 "nbformat_minor": 0,
 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "# \u5206\u652f, \u5faa\u73af\u548c\u5e8f\u5217\n",
      "\n",
      "## \u5206\u652f\u548c\u5faa\u73af"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from IPython.display import Image, display\n",
      "\n",
      "for i in range(1, 4):\n",
      "    if i == 1:\n",
      "        display(Image(url='http://img3.douban.com/view/photo/thumb/public/p946773286.jpg'))\n",
      "    elif i == 2:\n",
      "        display(Image(url='http://img3.douban.com/view/photo/thumb/public/p946773315.jpg'))\n",
      "    else:\n",
      "        display(Image(url='http://img3.douban.com/view/photo/thumb/public/p946773327.jpg'))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "html": [
        "<img src=\"http://img3.douban.com/view/photo/thumb/public/p946773286.jpg\" />"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.Image at 0x3063770>"
       ]
      },
      {
       "html": [
        "<img src=\"http://img3.douban.com/view/photo/thumb/public/p946773315.jpg\" />"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.Image at 0x3063770>"
       ]
      },
      {
       "html": [
        "<img src=\"http://img3.douban.com/view/photo/thumb/public/p946773327.jpg\" />"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.Image at 0x3063770>"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from IPython.display import HTML, display\n",
      "\n",
      "imgs = []\n",
      "for i in [2, 0, 1, 3]:\n",
      "    imgs.append('<img src=\"http://gelbooru.com/counter/%d.gif\">' % i)\n",
      "display(HTML(''.join(imgs)))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "html": [
        "<img src=\"http://gelbooru.com/counter/2.gif\"><img src=\"http://gelbooru.com/counter/0.gif\"><img src=\"http://gelbooru.com/counter/1.gif\"><img src=\"http://gelbooru.com/counter/3.gif\">"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.HTML at 0x3055bf0>"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def show_number(x):\n",
      "    ds = []\n",
      "    while True:\n",
      "        ds.append(x % 10)\n",
      "        x = x / 10\n",
      "        if x == 0:\n",
      "            break\n",
      "    imgs = []\n",
      "    for i in reversed(ds):\n",
      "        imgs.append('<img src=\"http://gelbooru.com/counter/%d.gif\">' % i)\n",
      "    display(HTML(''.join(imgs)))\n",
      "    \n",
      "for i in range(100, 110):\n",
      "    prime = True\n",
      "    for j in range(2, i - 1):\n",
      "        if i % j == 0:\n",
      "            prime = False\n",
      "            break\n",
      "    if not prime:\n",
      "        continue\n",
      "    show_number(i)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "html": [
        "<img src=\"http://gelbooru.com/counter/1.gif\"><img src=\"http://gelbooru.com/counter/0.gif\"><img src=\"http://gelbooru.com/counter/1.gif\">"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.HTML at 0x2f57290>"
       ]
      },
      {
       "html": [
        "<img src=\"http://gelbooru.com/counter/1.gif\"><img src=\"http://gelbooru.com/counter/0.gif\"><img src=\"http://gelbooru.com/counter/3.gif\">"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.HTML at 0x2f57290>"
       ]
      },
      {
       "html": [
        "<img src=\"http://gelbooru.com/counter/1.gif\"><img src=\"http://gelbooru.com/counter/0.gif\"><img src=\"http://gelbooru.com/counter/7.gif\">"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.HTML at 0x2f57290>"
       ]
      },
      {
       "html": [
        "<img src=\"http://gelbooru.com/counter/1.gif\"><img src=\"http://gelbooru.com/counter/0.gif\"><img src=\"http://gelbooru.com/counter/9.gif\">"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.HTML at 0x3055eb0>"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## \u8868\u63a8\u5bfc(list comprehension)"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from IPython.display import HTML, display\n",
      "\n",
      "img = '<img src=\"http://gelbooru.com/counter/%d.gif\">'\n",
      "display(HTML(''.join([img % i for i in range(10)])))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "html": [
        "<img src=\"http://gelbooru.com/counter/0.gif\"><img src=\"http://gelbooru.com/counter/1.gif\"><img src=\"http://gelbooru.com/counter/2.gif\"><img src=\"http://gelbooru.com/counter/3.gif\"><img src=\"http://gelbooru.com/counter/4.gif\"><img src=\"http://gelbooru.com/counter/5.gif\"><img src=\"http://gelbooru.com/counter/6.gif\"><img src=\"http://gelbooru.com/counter/7.gif\"><img src=\"http://gelbooru.com/counter/8.gif\"><img src=\"http://gelbooru.com/counter/9.gif\">"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.HTML at 0x3055830>"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from IPython.display import HTML, display\n",
      "\n",
      "img = '<img src=\"http://gelbooru.com/counter/%d.gif\">'\n",
      "display(HTML(''.join([img % i for i in range(10) if i % 2 == 0])))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "html": [
        "<img src=\"http://gelbooru.com/counter/0.gif\"><img src=\"http://gelbooru.com/counter/2.gif\"><img src=\"http://gelbooru.com/counter/4.gif\"><img src=\"http://gelbooru.com/counter/6.gif\"><img src=\"http://gelbooru.com/counter/8.gif\">"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.HTML at 0x3055870>"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "\u5b57\u5178\u4e5f\u53ef\u4ee5\u63a8\u5bfc(\u5b57\u5178\u63a8\u5bfc, dict comprehension):"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "print {a: b for a, b in [(1, 'one'), (2, 'two')]}"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "{1: 'one', 2: 'two'}\n"
       ]
      }
     ],
     "prompt_number": 6
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## \u751f\u6210\u5668(generator)\n",
      "\n",
      "\u751f\u6210\u5668\u4e5f\u662f\u4e00\u79cd\u5e8f\u5217."
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "print type(1), type(2.0), type('foo')\n",
      "print type(i for i in range(10))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "<type 'int'> <type 'float'> <type 'str'>\n",
        "<type 'generator'>\n"
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from IPython.display import HTML, display\n",
      "\n",
      "img = '<img src=\"http://gelbooru.com/counter/%d.gif\">'\n",
      "display(HTML(''.join(img % i for i in range(3))))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "html": [
        "<img src=\"http://gelbooru.com/counter/0.gif\"><img src=\"http://gelbooru.com/counter/1.gif\"><img src=\"http://gelbooru.com/counter/2.gif\">"
       ],
       "output_type": "display_data",
       "text": [
        "<IPython.core.display.HTML at 0x3055990>"
       ]
      }
     ],
     "prompt_number": 8
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "\u8fd9\u79cd\u5e8f\u5217\u53ef\u4ee5\u662f\u65e0\u9650\u957f\u7684:"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def natural_number():\n",
      "    i = 0\n",
      "    while True:\n",
      "        yield i\n",
      "        i += 1\n",
      "\n",
      "for i, _ in zip(natural_number(), range(10)):\n",
      "    print i"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "0\n",
        "1\n",
        "2\n",
        "3\n",
        "4\n",
        "5\n",
        "6\n",
        "7\n",
        "8\n",
        "9\n"
       ]
      }
     ],
     "prompt_number": 9
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## zip"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def even_number():\n",
      "    return (i for i in natural_number() if i % 2 == 0)\n",
      "\n",
      "print zip(even_number(), range(3))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "[(0, 0), (2, 1), (4, 2)]\n"
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "\u6ce8\u610f\u5143\u7ec4\u7684\u62ec\u53f7\u91cc\u5fc5\u9700\u81f3\u5c11\u6709\u4e00\u4e2a\u9017\u53f7. \u5982\u679c\u5c0f\u62ec\u53f7\u91cc\u6ca1\u6709\u9017\u53f7, \u5c31\u4ec5\u4ec5\u8868\u793a\u4e00\u79cd\u4f18\u5148\u7ea7.\n",
      "\n",
      "\u4e0e\u751f\u6210\u5668\u4e0d\u540c, \u8868\u63a8\u5bfc\u6ca1\u6709\u5ef6\u8fdf\u8ba1\u7b97\u7684\u6027\u8d28, \u4e0d\u80fd\u751f\u6210\u65e0\u9650\u957f\u5e8f\u5217(\u4f7f\u7528\u83dc\u5355\u91cc\u7684Kernel > Interrupt\u4e2d\u65ad\u7a0b\u5e8f):"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def even_number():\n",
      "    return [i for i in natural_number() if i % 2 == 0]\n",
      "\n",
      "print zip(even_number(), range(3))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    }
   ],
   "metadata": {}
  }
 ]
}