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"worksheets": [
{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h1>Chapter 10: Structures and Unions<h1>"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.1, Page Number: 223<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class inv_type:\n",
" def __init__(self):\n",
" self.item=None\n",
" self.cost=0\n",
" self.retail=0\n",
" self.on_hand=0\n",
" self.lead_time=0\n",
"\n",
"#Variable declaration\n",
"size=100 \n",
"invtry = []*size\n",
"i=5 #User iput for menu selection\n",
"\n",
"#Initialize the array\n",
"def init_list():\n",
" for t in range(size):\n",
" invtry.append(inv_type())\n",
" \n",
"#get a menu selection\n",
"def menu():\n",
" global i\n",
" print \"(E)nter\"\n",
" print \"(D)isplay\"\n",
" print \"(U)pdate\"\n",
" print \"(Q)uit\"\n",
" print \"choose one: \"\n",
" i-=1\n",
" return i\n",
"\n",
"#enter items into the list\n",
"def enter():\n",
" #find the first free structure\n",
" for i in range(size):\n",
" if not(invtry[i].item==None):\n",
" break\n",
" #i will be size if list is full\n",
" if i==size:\n",
" print \"List full.\"\n",
" return\n",
" input(i)\n",
" \n",
"#Input the information\n",
"def input(i):\n",
" #Enter information; User input\n",
" invtry[i].item=\"Gloves\"\n",
" invtry[i].cost=10\n",
" invtry[i].retail=25\n",
" invtry[i].on_hand=50\n",
" invtry[i].lead_time=10\n",
" \n",
"#Modify an existing item\n",
"def update():\n",
" name=\"Gloves\" #User input\n",
" for i in range(size):\n",
" if not(name==invtry[i].item):\n",
" break\n",
" if i==size:\n",
" print \"Item not found.\"\n",
" return\n",
" print \"Enter new information.\"\n",
" input(i)\n",
" \n",
"#Display the list\n",
"def display():\n",
" for t in range(size):\n",
" if not(invtry[t].item==None):\n",
" print invtry[t].item\n",
" print \"Cost: $\",invtry[t].cost\n",
" print \"Retail: $\",invtry[t].retail\n",
" print \"On hand: \",invtry[t].on_hand\n",
" print \"Resupply time: \",invtry[t].lead_time,\" days\"\n",
" \n",
"\n",
"init_list()\n",
"while True:\n",
" choice=menu()\n",
" if choice==4:\n",
" enter()\n",
" elif choice==3:\n",
" display()\n",
" elif choice==2:\n",
" update()\n",
" elif choice==1:\n",
" break"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"(E)nter\n",
"(D)isplay\n",
"(U)pdate\n",
"(Q)uit\n",
"choose one: \n",
"(E)nter\n",
"(D)isplay\n",
"(U)pdate\n",
"(Q)uit\n",
"choose one: \n",
"Gloves\n",
"Cost: $ 10\n",
"Retail: $ 25\n",
"On hand: 50\n",
"Resupply time: 10 days\n",
"(E)nter\n",
"(D)isplay\n",
"(U)pdate\n",
"(Q)uit\n",
"choose one: \n",
"Enter new information.\n",
"(E)nter\n",
"(D)isplay\n",
"(U)pdate\n",
"(Q)uit\n",
"choose one: \n"
]
}
],
"prompt_number": 11
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.2, Page Number: 226<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class sample:\n",
" a=None\n",
" ch=None\n",
" \n",
"def f1(parm):\n",
" print parm.a,\" \",parm.ch\n",
"\n",
"#declare arg\n",
"arg=sample() \n",
"\n",
"#initialize arg\n",
"arg.a=1000\n",
"arg.ch='X'\n",
"\n",
"#call function\n",
"f1(arg)\n",
" "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"1000 X\n"
]
}
],
"prompt_number": 12
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.3, Page Number: 227<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class stype:\n",
" a=None\n",
" b=None\n",
"\n",
"#Variable declaration\n",
"svar1=stype()\n",
"svar2=stype()\n",
"\n",
"svar1.a=svar1.b=10\n",
"svar2.a=svar2.b=20\n",
"\n",
"print \"Structures before assignment.\"\n",
"print \"svar1: \",svar1.a,' ',svar1.b\n",
"print \"svar1: \",svar2.a,' ',svar2.b\n",
"\n",
"svar2=svar1 #assign structures\n",
"\n",
"#Result\n",
"print \"\\nStructures before assignment.\"\n",
"print \"svar1: \",svar1.a,' ',svar1.b\n",
"print \"svar1: \",svar2.a,' ',svar2.b"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Structures before assignment.\n",
"svar1: 10 10\n",
"svar1: 20 20\n",
"\n",
"Structures before assignment.\n",
"svar1: 10 10\n",
"svar1: 10 10\n"
]
}
],
"prompt_number": 13
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.4, Page Number: 230<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"import datetime\n",
"\n",
"date=datetime.datetime.now()\n",
"\n",
"#Result\n",
"print date.time()"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"17:06:28.236000\n"
]
}
],
"prompt_number": 14
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.5, Page Number: 231<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import datetime\n",
"\n",
"date=datetime.datetime.now()\n",
"\n",
"#Result\n",
"print date.ctime()"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Sat Sep 14 17:07:14 2013\n"
]
}
],
"prompt_number": 15
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.6, Page Number: 232<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class mystruct:\n",
" a=None\n",
" b=None\n",
"\n",
"def f(var):\n",
" var[0].a=var[0].a*var[0].a\n",
" var[0].b=var[0].b/var[0].b\n",
" return var[0]\n",
" \n",
"#Variable declaration\n",
"x=[]\n",
"x.append(mystruct())\n",
"y=mystruct()\n",
"\n",
"#Initializing\n",
"x[0].a=10\n",
"x[0].b=20\n",
"\n",
"print \"Original x.a and x.b: \",x[0].a,' ',x[0].b\n",
"\n",
"y=f(x) #function call\n",
"\n",
"#Result\n",
"print \"Modified x.a and x.b: \",x[0].a,' ',x[0].b\n",
"print \"Modified y.a and y.b: \",y.a,' ',y.b\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Original x.a and x.b: 10 20\n",
"Modified x.a and x.b: 100 1\n",
"Modified y.a and y.b: 100 1\n"
]
}
],
"prompt_number": 16
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.7, Page Number: 239<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class swap_bytes:\n",
" ch=[0,0]\n",
"\n",
"#Exchange of bytes\n",
"def disp_binary(u):\n",
" t=128\n",
" while not(t==0):\n",
" if u&t:\n",
" print \"1 \",\n",
" else:\n",
" print \"0 \",\n",
" t=t/2\n",
"\n",
"#Variable declaration\n",
"sb=swap_bytes()\n",
"\n",
"sb.ch[0]=15\n",
"\n",
"print \"Original bytes: \",\n",
"disp_binary(sb.ch[1])\n",
"disp_binary(sb.ch[0])\n",
"\n",
"#Exchange bytes\n",
"temp=sb.ch[0]\n",
"sb.ch[0]=sb.ch[1]\n",
"sb.ch[1]=temp\n",
"\n",
"#Result\n",
"print \"\\nExchanged bytes: \",\n",
"disp_binary(sb.ch[1])\n",
"disp_binary(sb.ch[0])\n",
"\n",
"\n",
" "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Original bytes: 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 \n",
"Exchanged bytes: 0 0 0 0 1 1 1 1 0 0 0 0 0 0 0 0 \n"
]
}
],
"prompt_number": 17
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.8, Page Number: 240<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"ch='a'\n",
"\n",
"while True:\n",
" print \"\\n\",ch,\n",
" print bin(ord(ch)) #Display the bit pattern for each character\n",
" ch=chr(ord(ch)+1)\n",
" if ch=='r':\n",
" break"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"a 0b1100001\n",
"\n",
"b 0b1100010\n",
"\n",
"c 0b1100011\n",
"\n",
"d 0b1100100\n",
"\n",
"e 0b1100101\n",
"\n",
"f 0b1100110\n",
"\n",
"g 0b1100111\n",
"\n",
"h 0b1101000\n",
"\n",
"i 0b1101001\n",
"\n",
"j 0b1101010\n",
"\n",
"k 0b1101011\n",
"\n",
"l 0b1101100\n",
"\n",
"m 0b1101101\n",
"\n",
"n 0b1101110\n",
"\n",
"o 0b1101111\n",
"\n",
"p 0b1110000\n",
"\n",
"q 0b1110001\n"
]
}
],
"prompt_number": 18
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 10.9, Page Number: 242<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"#Variable declaration\n",
"ch=['X','Y']\n",
"c=\"\"\n",
"def disp_bits(u):\n",
" t=128\n",
" global c\n",
" while not(t==0):\n",
" if u&t:\n",
" c=c+\"1\"\n",
" else:\n",
" c=c+\"0\"\n",
" t=t/2 \n",
" return c\n",
"\n",
"#Result\n",
"print \"union as chars: \",ch[0],ch[1]\n",
"print \"union as integer: \",\n",
"c= disp_bits(ord(ch[1]))\n",
"c= disp_bits(ord(ch[0]))\n",
"print int(str(c),2)\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"union as chars: X Y\n",
"union as integer: 22872\n"
]
}
],
"prompt_number": 19
},
{
"cell_type": "code",
"collapsed": false,
"input": [],
"language": "python",
"metadata": {},
"outputs": []
}
],
"metadata": {}
}
]
}