{
 "metadata": {
  "language": "Julia",
  "name": ""
 },
 "nbformat": 3,
 "nbformat_minor": 0,
 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "#8 PLEAC Julia: File Contents"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "[PLEAC = Language Examples Alike Cookbook](http://pleac.sourceforge.net/)\n",
      "PLEAC examples are drawn from the \"Perl Cookbook\" by Tom Christiansen & Nathan Torkington, published by O'Reilly.  They provide a nice range of examples oriented toward data munging, the type of work I tend to want to do first when learning a new language.\n",
      "\n",
      "\n",
      "The Julia examples below are principally translations from the [Python version](http://pleac.sourceforge.net/pleac_python/)\n",
      "\n",
      "###Caution\n",
      "I'm learning as I go, so the code below probably doesn't represent best practice.  Your suggestions are welcome! \n",
      "Please file an issue or make a pull request to the [github repo](https://github.com/catawbasam/IJulia_PLEAC/).\n",
      "\n",
      "The examples are not complete. Missing items are generally noted in comments. "
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.0 Introduction"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#make a file\n",
      "contents=\"\"\"Here are\n",
      "a few\n",
      "lines of\n",
      "text content.\"\"\"\n",
      "\n",
      "fo=open(\"julia_file.txt\", \"w\")\n",
      "write(fo, contents)\n",
      "close(fo)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 1
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "fi=open(\"julia_file.txt\", \"r\")\n",
      "for line in readlines(fi)\n",
      "  line = rstrip(line)\n",
      "  size = length(line)\n",
      "  println(size)\n",
      "end\n",
      "close(fi)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "8"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n",
        "5\n",
        "8\n",
        "13\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "fi=open(\"julia_file.txt\", \"r\")\n",
      "for line in readlines(fi)\n",
      "  println(length(rstrip(line)))\n",
      "end\n",
      "close(fi)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "8\n",
        "5\n",
        "8\n",
        "13\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "al=readlines(open(\"julia_file.txt\", \"r\"))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 4,
       "text": [
        "4-element Array{Any,1}:\n",
        " \"Here are\\n\"   \n",
        " \"a few\\n\"      \n",
        " \"lines of\\n\"   \n",
        " \"text content.\""
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "t=readall(open(\"julia_file.txt\", \"r\"))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 5,
       "text": [
        "\"Here are\\na few\\nlines of\\ntext content.\""
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "t"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 6,
       "text": [
        "\"Here are\\na few\\nlines of\\ntext content.\""
       ]
      }
     ],
     "prompt_number": 6
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "w=readdlm(open(\"julia_file.txt\", \"r\"), ' ')[1] #first word"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 7,
       "text": [
        "\"Here\""
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "fi=open(\"julia_file.txt2\", \"w\")\n",
      "writedlm(fi, [\"One\",\"Two\",\"Three\"], ' ')\n",
      "close(fi)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 8
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "help(seek)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Loading help data..."
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Base.seek(s, pos)\n",
        "\n",
        "   Seek a stream to the given position.\n"
       ]
      }
     ],
     "prompt_number": 9
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "fi=open(\"julia_file.txt\", \"r\")\n",
      "ba=readbytes(fi, 4096)\n",
      "ba'"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 10,
       "text": [
        "1x37 Array{Uint8,2}:\n",
        " 0x48  0x65  0x72  0x65  0x20  0x61  \u2026  0x6e  0x74  0x65  0x6e  0x74  0x2e"
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "seek(fi,12)  #seek to byte 12\n",
      "println(\"I'm $(position(fi)) bytes from the start of the file\")"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "I'm 12 bytes from the start of the file"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n"
       ]
      }
     ],
     "prompt_number": 11
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "seekstart(fi) #seek to start\n",
      "seekend(fi) #seek to end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 12,
       "text": [
        "IOStream(<file julia_file.txt>)"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "seekend(fi)\n",
      "skip(fi, -2)  #relative seek\n",
      "position(fi)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 13,
       "text": [
        "35"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "position(fi)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 14,
       "text": [
        "35"
       ]
      }
     ],
     "prompt_number": 14
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# NOT IMPLEMENTED:\n",
      "# pos = os.lseek(myfile.fileno(),0,1)  #?? what does this do?"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 15
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.1 Reading Lines with Continuation Characters"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#not implemented"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 16
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.2 Counting Lines (or Paragraphs or Records) in a File"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "open(\"julia_file.txt\", \"r\") do fi\n",
      "   lines= readlines(fi)\n",
      "end\n",
      "length(lines)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "WARNING: "
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n"
       ]
      },
      {
       "ename": "LoadError",
       "evalue": "lines not defined\nat In[17]:4",
       "output_type": "pyerr",
       "traceback": [
        "lines not defined\nat In[17]:4"
       ]
      }
     ],
     "prompt_number": 17
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "t=readall(open(\"julia_file.txt\", \"r\"))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "backtraces on your platform are often misleading or partially incorrect\n"
       ]
      },
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 18,
       "text": [
        "\"Here are\\na few\\nlines of\\ntext content.\""
       ]
      }
     ],
     "prompt_number": 18
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "para_count = length(split(t, \"in\"))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 19,
       "text": [
        "2"
       ]
      }
     ],
     "prompt_number": 19
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.3 Processing Every Word in a File"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#simple word count\n",
      "words=split(t)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 20,
       "text": [
        "8-element Array{String,1}:\n",
        " \"Here\"    \n",
        " \"are\"     \n",
        " \"a\"       \n",
        " \"few\"     \n",
        " \"lines\"   \n",
        " \"of\"      \n",
        " \"text\"    \n",
        " \"content.\""
       ]
      }
     ],
     "prompt_number": 20
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "word_dict=Dict()\n",
      "for w in words\n",
      "  word_dict[w] = get(word_dict, w, 0)+1\n",
      "end\n",
      "word_dict"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 21,
       "text": [
        "{\"text\"=>1,\"content.\"=>1,\"are\"=>1,\"few\"=>1,\"Here\"=>1,\"lines\"=>1,\"of\"=>1,\"a\"=>1}"
       ]
      }
     ],
     "prompt_number": 21
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "####Cleaner results using TextAnalysis"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "using TextAnalysis"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 22
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "tokens(Document(t))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 23,
       "text": [
        "8-element Array{UTF8String,1}:\n",
        " \"Here\"    \n",
        " \"are\"     \n",
        " \"a\"       \n",
        " \"few\"     \n",
        " \"lines\"   \n",
        " \"of\"      \n",
        " \"text\"    \n",
        " \"content.\""
       ]
      }
     ],
     "prompt_number": 23
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "words=split(remove_punctuation!(Document(t)))  #we could remove numbers too."
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 24,
       "text": [
        "8-element Array{String,1}:\n",
        " \"Here\"   \n",
        " \"are\"    \n",
        " \"a\"      \n",
        " \"few\"    \n",
        " \"lines\"  \n",
        " \"of\"     \n",
        " \"text\"   \n",
        " \"content\""
       ]
      }
     ],
     "prompt_number": 24
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "word_dict=Dict()\n",
      "for w in words\n",
      "  word_dict[w] = get(word_dict, w, 0)+1\n",
      "end\n",
      "word_dict"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 25,
       "text": [
        "{\"text\"=>1,\"are\"=>1,\"few\"=>1,\"Here\"=>1,\"lines\"=>1,\"content\"=>1,\"of\"=>1,\"a\"=>1}"
       ]
      }
     ],
     "prompt_number": 25
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#line frequency count\n",
      "lines=readlines(open(\"julia_file.txt\", \"r\"))\n",
      "line_dict=Dict()\n",
      "for w in lines\n",
      "  line_dict[w] = get(line_dict, w, 0)+1\n",
      "end\n",
      "line_dict"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 26,
       "text": [
        "{\"lines of\\n\"=>1,\"Here are\\n\"=>1,\"a few\\n\"=>1,\"text content.\"=>1}"
       ]
      }
     ],
     "prompt_number": 26
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.4 Reading a File Backwards by Line or Paragraph"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "lines= reverse( readlines(open(\"julia_file.txt\", \"r\")) )"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 27,
       "text": [
        "4-element Array{Any,1}:\n",
        " \"text content.\"\n",
        " \"lines of\\n\"   \n",
        " \"a few\\n\"      \n",
        " \"Here are\\n\"   "
       ]
      }
     ],
     "prompt_number": 27
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.5 Trailing a Growing File"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "fi=open(\"julia_file.txt\", \"r\")\n",
      "seekend(fi)\n",
      "endpos = position(fi)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 28,
       "text": [
        "37"
       ]
      }
     ],
     "prompt_number": 28
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "i=1\n",
      "while i<3 #or while true\n",
      "  sleep(1)\n",
      "  seekend(fi)\n",
      "  if position(fi)>endpos\n",
      "    endpos=position(fi)\n",
      "    println(\"time: $i. new size: $endpos\")\n",
      "  end\n",
      "  i=i+1\n",
      "end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 29
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "close(fi)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 30
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.6 Picking a Random Line from a File"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "lines= reverse( readlines(open(\"julia_file.txt\", \"r\")) )\n",
      "length(lines)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 31,
       "text": [
        "4"
       ]
      }
     ],
     "prompt_number": 31
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "pick = rand(1:length(lines))\n",
      "lines[pick]"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 32,
       "text": [
        "\"Here are\\n\""
       ]
      }
     ],
     "prompt_number": 32
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.7 Randomizing All Lines"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "using Distributions"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 33
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "shuffle(lines)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 34,
       "text": [
        "4-element Array{Any,1}:\n",
        " \"a few\\n\"      \n",
        " \"text content.\"\n",
        " \"Here are\\n\"   \n",
        " \"lines of\\n\"   "
       ]
      }
     ],
     "prompt_number": 34
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.8 Reading a Particular Line in a File"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "DESIRED_LINE=3\n",
      "lines[DESIRED_LINE]"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 35,
       "text": [
        "\"a few\\n\""
       ]
      }
     ],
     "prompt_number": 35
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.9 Processing Variable-Length Text Fields"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "pattern=\" \"\n",
      "record = lines[1]\n",
      "split(record)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 36,
       "text": [
        "2-element Array{String,1}:\n",
        " \"text\"    \n",
        " \"content.\""
       ]
      }
     ],
     "prompt_number": 36
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.10 Removing the Last Line of a File"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#create test file\n",
      "#make a file\n",
      "contents=\"\"\"Here are\n",
      "a few\n",
      "lines of\n",
      "text content.\"\"\"\n",
      "\n",
      "fo=open(\"julia_file.txt\", \"w\")\n",
      "write(fo, contents)\n",
      "close(fo)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 37
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "fi=open(\"julia_file.txt\", \"r+\")\n",
      "pos=0\n",
      "prev_pos=0\n",
      "for ln in eachline(fi)\n",
      "  prev_pos = pos\n",
      "  pos = position(fi)\n",
      "end\n",
      "close(fi)\n",
      "println(prev_pos)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "Warning: could not import Base.foldl into NumericExtensions\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "24"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "Warning: could not import Base.foldr into NumericExtensions\n"
       ]
      }
     ],
     "prompt_number": 38
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "cp(\"julia_file.txt\", \"julia_file2.txt\")\n",
      "open(\"julia_file2.txt\", \"w\") do fi\n",
      "    truncate(fi, prev_pos)\n",
      "end\n",
      "\n",
      "trunc8 = readall(open(\"julia_file.txt\", \"r\"))\n",
      "open(\"julia_file2.txt\", \"w\") do fo\n",
      "    write(fo, trunc8[1:prev_pos])\n",
      "end\n",
      "\n",
      "result = readall(open(\"julia_file2.txt\", \"r\"))\n",
      "result"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 39,
       "text": [
        "\"Here are\\na few\\nlines of\\n\""
       ]
      }
     ],
     "prompt_number": 39
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.11 Processing Binary Files"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "open(\"julia_file.txt\", \"r\") do fi\n",
      "    ba=readbytes(fi)\n",
      "end\n",
      "ba'"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 40,
       "text": [
        "1x37 Array{Uint8,2}:\n",
        " 0x48  0x65  0x72  0x65  0x20  0x61  \u2026  0x6e  0x74  0x65  0x6e  0x74  0x2e"
       ]
      }
     ],
     "prompt_number": 40
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.12 Using Random-Access I/O"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "function readstring(stream, numchars)\n",
      "  bytes=readbytes(stream, numchars)\n",
      "  return join([char(v) for v in bytes])\n",
      "end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 41,
       "text": [
        "readstring (generic function with 1 method)"
       ]
      }
     ],
     "prompt_number": 41
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#make a file : 2 fields of 4 chars (+ \\n) = 9 characters per line\n",
      "contents=\"\"\"   a   b\n",
      "blah  at\n",
      "line  of\n",
      "text1234\"\"\"\n",
      "\n",
      "open(\"julia_fixed.dat\", \"w\") do fo\n",
      "    write(fo, contents)\n",
      "end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 42,
       "text": [
        "35"
       ]
      }
     ],
     "prompt_number": 42
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "recsize=8+1  # 8 characters of data + line ending\n",
      "recno=2\n",
      "address = recsize * recno \n",
      "open(\"julia_fixed.dat\", \"r\") do fi\n",
      "    seek(fi,address)\n",
      "    println(readstring(fi, recsize))\n",
      "end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "line  of\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n"
       ]
      }
     ],
     "prompt_number": 43
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.13 Updating a Random-Access File"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "open(\"julia_fixed.dat\", \"r+\") do fi\n",
      "    seek(fi,address)\n",
      "    recstr = readstring(fi, recsize)\n",
      "    newrec = uppercase(recstr)\n",
      "    seek(fi,address)\n",
      "    write(fi,newrec)\n",
      "end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 52,
       "text": [
        "9"
       ]
      }
     ],
     "prompt_number": 52
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "open(\"julia_fixed.dat\", \"r\") do fi\n",
      "    dt=readall(fi)\n",
      "    print(dt)\n",
      "end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "   a   b\n",
        "blah  at\n",
        "LINE  OF\n",
        "text1234"
       ]
      }
     ],
     "prompt_number": 54
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.14 Reading a String from a Binary File"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#NOT IMPLEMENTED"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 46
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.15 Reading Fixed-Length Records"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "Pkg.add(\"IniFile\")"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "INFO: "
       ]
      },
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "No packages to install, update or remove.\n",
        "INFO: REQUIRE updated.\n"
       ]
      }
     ],
     "prompt_number": 85
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# define a packable binary record\n",
      "using StrPack\n",
      "@struct  type TstStr\n",
      "    int1::Int64\n",
      "    float1::Float64\n",
      "end\n",
      "RECORDSIZE=sizeof(TstStr)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 71,
       "text": [
        "16"
       ]
      }
     ],
     "prompt_number": 71
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#write out sample data\n",
      "rec=TstStr(4455, 556.32)\n",
      "open(\"bintest.dat\",\"w\") do fo\n",
      "    pack(fo, rec)\n",
      "    pack(fo, TstStr(3455, 556.32))\n",
      "    pack(fo, TstStr(6453, 656.32))    \n",
      "end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "WARNING: "
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n",
        "\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "max(x) is deprecated, use maximum(x) instead.\n",
        " in depwarn at deprecated.jl:29\n",
        " in string at ascii.jl:35\n",
        "WARNING: max(x) is deprecated, use maximum(x) instead.\n",
        " in depwarn at deprecated.jl:29\n",
        " in string at ascii.jl:35\n",
        "WARNING: max(x) is deprecated, use maximum(x) instead.\n",
        " in depwarn at deprecated.jl:29\n",
        " in string at ascii.jl:35\n"
       ]
      },
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 81,
       "text": [
        "16"
       ]
      }
     ],
     "prompt_number": 81
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "open(\"bintest.dat\",\"r\") do fi\n",
      "    seek(fi, RECORDSIZE)   # \"rewind\" to the beginning of the buffer\n",
      "    s2 = unpack(fi, TstStr)\n",
      "    println(s2)\n",
      "end"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "WARNING: "
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "TstStr(3455,556.32)\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "max(x) is deprecated, use maximum(x) instead.\n",
        " in depwarn at deprecated.jl:29\n",
        " in string at ascii.jl:35\n"
       ]
      }
     ],
     "prompt_number": 84
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.16 Reading Configuration Files"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "using IniFile\n",
      "ini = Inifile()\n",
      "read(ini, \"test.ini\")\n",
      "get(ini, \"section 1\", \"strname1\") #== \"section1name1\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 87,
       "text": [
        "\"section1name1\""
       ]
      }
     ],
     "prompt_number": 87
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "##8.17 Testing a File for Trustworthiness"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#Will not implement"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 49
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## Programs"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#Will not implement"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 50
    }
   ],
   "metadata": {}
  }
 ]
}