{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# Tuples\n",
"![\"Open](\"https://colab.research.google.com/assets/colab-badge.svg\")
\n",
"\n",
"- http://openbookproject.net/thinkcs/python/english3e/tuples.html\n",
"- containers used for grouping data values surrounded with parenthesis\n",
"- data values in tuples are called elements/items/members\n",
"- two major operations done with tuples are:\n",
" 1. packing (creating tuples)\n",
" 2. unpacking (storing data into individual variables)"
]
},
{
"cell_type": "code",
"execution_count": 1,
"metadata": {},
"outputs": [],
"source": [
"year_born = (\"Paris Hilton\", 1981) # tuple packing"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"('Paris Hilton', 1981)\n"
]
}
],
"source": [
"print(year_born)"
]
},
{
"cell_type": "code",
"execution_count": 11,
"metadata": {},
"outputs": [],
"source": [
"star = \"Paris\", 'J', 'Hilton', 1981, 32, 1.2 # tuple packing"
]
},
{
"cell_type": "code",
"execution_count": 12,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"('Paris', 'J', 'Hilton', 1981, 32, 1.2)"
]
},
"execution_count": 12,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"star"
]
},
{
"cell_type": "code",
"execution_count": 13,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"tuple"
]
},
"execution_count": 13,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"type(star)"
]
},
{
"cell_type": "code",
"execution_count": 14,
"metadata": {},
"outputs": [],
"source": [
"# tuple assignment\n",
"fname, mi, lname, year, age, income = star # tuple unpacking; \n",
"# no. of variables must match no. tuple values"
]
},
{
"cell_type": "code",
"execution_count": 9,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"'Paris'"
]
},
"execution_count": 9,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"fname"
]
},
{
"cell_type": "code",
"execution_count": 10,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"'Hilton'"
]
},
"execution_count": 10,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"lname"
]
},
{
"cell_type": "code",
"execution_count": 11,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1.2\n"
]
}
],
"source": [
"print(income)"
]
},
{
"cell_type": "code",
"execution_count": 12,
"metadata": {},
"outputs": [],
"source": [
"# swap values of two variables\n",
"a = 100\n",
"b = 200\n",
"a, b = b, a"
]
},
{
"cell_type": "code",
"execution_count": 13,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"200 100\n"
]
}
],
"source": [
"print(a, b)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Member access\n",
"- each member of tuple can be accessed using [ index ] operator\n",
"- index is 0 based or starts from 0"
]
},
{
"cell_type": "code",
"execution_count": 1,
"metadata": {},
"outputs": [],
"source": [
"name = ('John', 'A.', 'Smith')"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"John A. Smith\n"
]
}
],
"source": [
"print(name[0], name[1], name[2])"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## len built-in function\n",
"- gives the length (no. of elements) of tuple"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"3"
]
},
"execution_count": 4,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"len(name)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Tuple membership\n",
"- **in** and **not in** boolean operators let's you check for membership"
]
},
{
"cell_type": "code",
"execution_count": 7,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"True"
]
},
"execution_count": 7,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"'John' in name"
]
},
{
"cell_type": "code",
"execution_count": 8,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"False"
]
},
"execution_count": 8,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"'B.' in name"
]
},
{
"cell_type": "code",
"execution_count": 9,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"True"
]
},
"execution_count": 9,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"'Jake' not in name"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Tuples can be returned from a function"
]
},
{
"cell_type": "code",
"execution_count": 29,
"metadata": {},
"outputs": [],
"source": [
"def maxAndMin(a, b, c, d, e):\n",
" myMax = a #max(a, b, c, d, e)\n",
" if myMax < b:\n",
" myMax = b\n",
" if myMax < c:\n",
" myMax = c\n",
" if myMax < d:\n",
" myMax = d\n",
" if myMax < e:\n",
" myMax = e\n",
" values = [a, b, c, d, e]\n",
" myMin = min(values)\n",
" return (myMax, myMin)\n",
" "
]
},
{
"cell_type": "code",
"execution_count": 30,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"max = 100 min= 5\n"
]
}
],
"source": [
"ab = maxAndMin(10, 20, 5, 100, 34)\n",
"print('max =', ab[0], 'min=', ab[1])"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Tuples are immutable\n",
"- can't change tuple in-place or update its elements similar to string"
]
},
{
"cell_type": "code",
"execution_count": 5,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1\n"
]
}
],
"source": [
"a = (1, 2, 3)\n",
"print(a[0])"
]
},
{
"cell_type": "code",
"execution_count": 6,
"metadata": {},
"outputs": [
{
"ename": "TypeError",
"evalue": "'tuple' object does not support item assignment",
"output_type": "error",
"traceback": [
"\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
"\u001b[0;31mTypeError\u001b[0m Traceback (most recent call last)",
"\u001b[0;32m\u001b[0m in \u001b[0;36m\u001b[0;34m()\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0ma\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;36m0\u001b[0m\u001b[0;34m]\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;36m100\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
"\u001b[0;31mTypeError\u001b[0m: 'tuple' object does not support item assignment"
]
}
],
"source": [
"a[0] = 100"
]
}
],
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"display_name": "Python 3",
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"name": "python3"
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