6 - If-else.ipynb

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   "source": [
    "# Python if ... else Statement"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
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   "source": [
    "The **if…elif…else** statement is used in Python for decision making."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "colab_type": "text",
    "id": "B4c_NjAlefRA"
   },
   "source": [
    "# if statement syntax"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {
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    "id": "kJmNXz9_efRB"
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   "source": [
    "    if test expression:\n",
    "\n",
    "        statement(s)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
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   },
   "source": [
    "The program evaluates the test expression and will execute statement(s) only if the text expression is True.\n",
    "\n",
    "If the text expression is False, the statement(s) is not executed."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
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    "id": "2j1VzC47efRD"
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   "source": [
    "Python interprets non-zero values as True. None and 0 are interpreted as False."
   ]
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  {
   "cell_type": "markdown",
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   "source": [
    "# Example"
   ]
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   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "This will print always\n"
     ]
    }
   ],
   "source": [
    "num = 10\n",
    "\n",
    "# try 0, -1 and None\n",
    "if None:\n",
    "    print(\"Number is positive\")\n",
    "print(\"This will print always\")      #This print statement always print\n",
    "\n",
    "#change number \n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
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   "source": [
    "# if ... else Statement"
   ]
  },
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   "cell_type": "markdown",
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   "source": [
    "# Syntax:"
   ]
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   "source": [
    "    if test expression:\n",
    "    \n",
    "        Body of if\n",
    "\n",
    "    else: \n",
    "    \n",
    "        Body of else"
   ]
  },
  {
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   "source": [
    "# Example"
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   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Positive number\n"
     ]
    }
   ],
   "source": [
    "num = 10\n",
    "if num > 0:\n",
    "    print(\"Positive number\")\n",
    "else:\n",
    "    print(\"Negative Number\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "colab_type": "text",
    "id": "FhL5F5DJefRR"
   },
   "source": [
    "# if...elif...else Statement"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
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    "id": "n5gOJbuUefRS"
   },
   "source": [
    "# Syntax:"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {
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    "id": "NK9FpkhiefRT"
   },
   "source": [
    "    if test expression:\n",
    "\n",
    "        Body of if\n",
    "    elif test expression:\n",
    "    \n",
    "        Body of elif\n",
    "    else: \n",
    "    \n",
    "        Body of else"
   ]
  },
  {
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   "source": [
    "# Example:"
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   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "ZERO\n"
     ]
    }
   ],
   "source": [
    "num = 0\n",
    "\n",
    "if num > 0:\n",
    "    print(\"Positive number\")\n",
    "elif num == 0:\n",
    "    print(\"ZERO\")\n",
    "else:\n",
    "    print(\"Negative Number\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "colab_type": "text",
    "id": "Sp98_OGyefRZ"
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   "source": [
    "# Nested if Statements"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
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    "id": "Ss3GbcNTefRZ"
   },
   "source": [
    "We can have a if...elif...else statement inside another if...elif...else statement. This is called nesting in computer programming."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
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    "id": "_WOwMeijefRZ"
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   "source": [
    "# Example:"
   ]
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   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Positive number\n"
     ]
    }
   ],
   "source": [
    "num = 10.5\n",
    "\n",
    "if num >= 0:\n",
    "    if num == 0:\n",
    "        print(\"Zero\")\n",
    "    else:\n",
    "        print(\"Positive number\")\n",
    "else:\n",
    "    print(\"Negative Number\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "colab_type": "text",
    "id": "29bb4cB2efRc"
   },
   "source": [
    "# Python program to find the largest element among three Numbers"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 0,
   "metadata": {
    "colab": {
     "autoexec": {
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    "outputId": "7f6c6563-784d-40a6-cafd-eb999ed77e2a"
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Largest element among three numbers is: 50\n"
     ]
    }
   ],
   "source": [
    "num1 = 10\n",
    "num2 = 50\n",
    "num3 = 15\n",
    "\n",
    "if (num1 >= num2) and (num1 >= num3):           #logical operator   and\n",
    "    largest = num1\n",
    "elif (num2 >= num1) and (num2 >= num3):\n",
    "    largest = num2\n",
    "else:\n",
    "    largest = num3\n",
    "print(\"Largest element among three numbers is: {}\".format(largest))"
   ]
  },
  {
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   "execution_count": 0,
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   "source": []
  }
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