46. range.ipynb

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "range(0, 10)\n",
      "x[0] is 0\n",
      "x[5] is 5\n",
      "x[9] is 9\n",
      "x[6] is 6\n"
     ]
    },
    {
     "ename": "IndexError",
     "evalue": "range object index out of range",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mIndexError\u001b[0m                                Traceback (most recent call last)",
      "Cell \u001b[1;32mIn[4], line 7\u001b[0m\n\u001b[0;32m      5\u001b[0m \u001b[38;5;28mprint\u001b[39m(\u001b[38;5;124mf\u001b[39m\u001b[38;5;124m\"\u001b[39m\u001b[38;5;124mx[9] is \u001b[39m\u001b[38;5;132;01m{\u001b[39;00mx[\u001b[38;5;241m9\u001b[39m]\u001b[38;5;132;01m}\u001b[39;00m\u001b[38;5;124m\"\u001b[39m)\n\u001b[0;32m      6\u001b[0m \u001b[38;5;28mprint\u001b[39m(\u001b[38;5;124mf\u001b[39m\u001b[38;5;124m\"\u001b[39m\u001b[38;5;124mx[6] is \u001b[39m\u001b[38;5;132;01m{\u001b[39;00mx[\u001b[38;5;241m6\u001b[39m]\u001b[38;5;132;01m}\u001b[39;00m\u001b[38;5;124m\"\u001b[39m)\n\u001b[1;32m----> 7\u001b[0m \u001b[38;5;28mprint\u001b[39m(\u001b[38;5;124mf\u001b[39m\u001b[38;5;124m\"\u001b[39m\u001b[38;5;124mx[10 is \u001b[39m\u001b[38;5;132;01m{\u001b[39;00m\u001b[43mx\u001b[49m\u001b[43m[\u001b[49m\u001b[38;5;241;43m10\u001b[39;49m\u001b[43m]\u001b[49m\u001b[38;5;132;01m}\u001b[39;00m\u001b[38;5;124m]\u001b[39m\u001b[38;5;124m\"\u001b[39m)\n",
      "\u001b[1;31mIndexError\u001b[0m: range object index out of range"
     ]
    }
   ],
   "source": [
    "x = range(10)\n",
    "print(x)\n",
    "print(f\"x[0] is {x[0]}\")\n",
    "print(f\"x[5] is {x[5]}\")\n",
    "print(f\"x[9] is {x[9]}\")\n",
    "print(f\"x[6] is {x[6]}\")\n",
    "print(f\"x[10 is {x[10]}]\") # it will raise an"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0\n",
      "1\n",
      "2\n",
      "3\n",
      "4\n"
     ]
    }
   ],
   "source": [
    "for i in range(5):\n",
    "    print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "2\n",
      "3\n",
      "4\n",
      "5\n",
      "6\n",
      "7\n",
      "8\n",
      "9\n"
     ]
    }
   ],
   "source": [
    "for i in range(2, 10):\n",
    "    print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "2\n",
      "4\n",
      "6\n",
      "8\n",
      "10\n",
      "12\n",
      "14\n"
     ]
    }
   ],
   "source": [
    "for i in range(2, 15, 2):\n",
    "    print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "2\n",
      "5\n",
      "8\n",
      "11\n",
      "14\n"
     ]
    }
   ],
   "source": [
    "for i in range(2, 15, 3):\n",
    "    print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "for i in range(1, 15, -3):\n",
    "    print(i)\n",
    "\n",
    "# It will not give any output because:\n",
    "# i = 1, j = 15, k = -3\n",
    "#i, i+k, i+2k, i+3k, ..... j-1\n",
    "#=> 1, -2 (1+(-3)), -5 (1+2*(-3)), -8 (1+3*(-3)), ....\n",
    "#=> 1, -2, -5, .....\n",
    "\n",
    "#The loop didn't print anything because the range() \n",
    "#with a negative step (-3) expects the start value (1) \n",
    "#to be greater than the stop value (15). \n",
    "#Since this condition isn't met, the range generates no numbers!"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [
    {
     "ename": "ValueError",
     "evalue": "range() arg 3 must not be zero",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mValueError\u001b[0m                                Traceback (most recent call last)",
      "Cell \u001b[1;32mIn[26], line 1\u001b[0m\n\u001b[1;32m----> 1\u001b[0m \u001b[38;5;28;01mfor\u001b[39;00m i \u001b[38;5;129;01min\u001b[39;00m \u001b[38;5;28;43mrange\u001b[39;49m\u001b[43m(\u001b[49m\u001b[38;5;241;43m3\u001b[39;49m\u001b[43m,\u001b[49m\u001b[43m \u001b[49m\u001b[38;5;241;43m9\u001b[39;49m\u001b[43m,\u001b[49m\u001b[43m \u001b[49m\u001b[38;5;241;43m0\u001b[39;49m\u001b[43m)\u001b[49m:\n\u001b[0;32m      2\u001b[0m     \u001b[38;5;28mprint\u001b[39m(i)\n\u001b[0;32m      4\u001b[0m \u001b[38;5;66;03m# Python raises a ValueError for step=0 in range() to prevent infinite loops or undefined behavior.\u001b[39;00m\n\u001b[0;32m      5\u001b[0m \u001b[38;5;66;03m# Key Rule: The step must be non-zero:\u001b[39;00m\n\u001b[0;32m      6\u001b[0m \u001b[38;5;66;03m# - Positive Step: range(3, 9, 1) → 3, 4, 5, 6, 7, 8.\u001b[39;00m\n\u001b[0;32m      7\u001b[0m \u001b[38;5;66;03m# - Negative Step: range(9, 3, -1) → 9, 8, 7, 6, 5, 4.\u001b[39;00m\n\u001b[0;32m      8\u001b[0m \u001b[38;5;66;03m# To control progression manually, use an if condition or break instead of step=0.\u001b[39;00m\n",
      "\u001b[1;31mValueError\u001b[0m: range() arg 3 must not be zero"
     ]
    }
   ],
   "source": [
    "for i in range(3, 9, 0):\n",
    "    print(i)\n",
    "\n",
    "# Python raises a ValueError for step=0 in range() to prevent infinite loops or undefined behavior.\n",
    "# Key Rule: The step must be non-zero:\n",
    "# - Positive Step: range(3, 9, 1) → 3, 4, 5, 6, 7, 8.\n",
    "# - Negative Step: range(9, 3, -1) → 9, 8, 7, 6, 5, 4.\n",
    "# To control progression manually, use an if condition or break instead of step=0."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "'str' object cannot be interpreted as an integer",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "Cell \u001b[1;32mIn[27], line 1\u001b[0m\n\u001b[1;32m----> 1\u001b[0m \u001b[38;5;28;01mfor\u001b[39;00m i \u001b[38;5;129;01min\u001b[39;00m \u001b[38;5;28;43mrange\u001b[39;49m\u001b[43m(\u001b[49m\u001b[38;5;124;43m\"\u001b[39;49m\u001b[38;5;124;43m1\u001b[39;49m\u001b[38;5;124;43m\"\u001b[39;49m\u001b[43m,\u001b[49m\u001b[43m \u001b[49m\u001b[38;5;241;43m10\u001b[39;49m\u001b[43m,\u001b[49m\u001b[43m \u001b[49m\u001b[38;5;241;43m1\u001b[39;49m\u001b[43m)\u001b[49m:\n\u001b[0;32m      2\u001b[0m     \u001b[38;5;28mprint\u001b[39m(i)\n\u001b[0;32m      4\u001b[0m \u001b[38;5;66;03m# the range function expects integer values as arguments\u001b[39;00m\n\u001b[0;32m      5\u001b[0m \u001b[38;5;66;03m# Here, the first argument is a string (\"1\") instead of an integer (1), \u001b[39;00m\n\u001b[0;32m      6\u001b[0m \u001b[38;5;66;03m# which will raise a TypeError since python cannot interpret the string \"1\" \u001b[39;00m\n\u001b[0;32m      7\u001b[0m \u001b[38;5;66;03m# as an integer for the range function\u001b[39;00m\n",
      "\u001b[1;31mTypeError\u001b[0m: 'str' object cannot be interpreted as an integer"
     ]
    }
   ],
   "source": [
    "for i in range(\"1\", 10, 1):\n",
    "    print(i)\n",
    "\n",
    "# the range function expects integer values as arguments\n",
    "# Here, the first argument is a string (\"1\") instead of an integer (1), \n",
    "# which will raise a TypeError since python cannot interpret the string \"1\" \n",
    "# as an integer for the range function"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {},
   "outputs": [],
   "source": [
    "for i in range(10, 0):\n",
    "    print(i)\n",
    "\n",
    "# The range() function requires the second argument \n",
    "# to be less than the first when using a positive step.\n",
    "# Since no step is specified, it defaults to k = 1, and thus no values will be generated from 10 to 0\n",
    "# as it will start from 10 and try to move ahead as k is 1 and series.. 10, 11, 12.... will not reach 0"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "10\n",
      "9\n",
      "8\n",
      "7\n",
      "6\n",
      "5\n",
      "4\n",
      "3\n",
      "2\n",
      "1\n"
     ]
    }
   ],
   "source": [
    "for i in range(10, 0, -1):\n",
    "    print(i)\n",
    "\n",
    "# but if we keep k=-1 instead of k = 1 it will generate a reverse series"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "-20\n",
      "-18\n",
      "-16\n",
      "-14\n",
      "-12\n",
      "-10\n",
      "-8\n",
      "-6\n",
      "-4\n"
     ]
    }
   ],
   "source": [
    "for i in range(-20, -2, 2):\n",
    "    print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 36,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "5050\n"
     ]
    }
   ],
   "source": [
    "\"\"\"\n",
    "Print sum of all numbers from 1 to 100!\n",
    "\"\"\"\n",
    "\n",
    "\n",
    "sum = 0\n",
    "for i in range(1, 101):\n",
    "    sum += i\n",
    "print(sum)"
   ]
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 3",
   "language": "python",
   "name": "python3"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.11.0"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 2
}