sq_01_python_intro/jupyter_book/05_texte.ipynb.orig

{
 "cells": [
  {
   "cell_type": "markdown",
   "id": "df41324e-da47-4d61-a80d-a7bd29198c8d",
   "metadata": {},
   "source": [
    "# Texte\n",
    "\n",
    "Bisher haben wir nur mit Zahlen gearbeitet, d.h. Python als besseren Taschenrechner verwendet.\n",
    "Jetzt wollen wir auch Texte verwenden.\n",
    "\n",
    "Text wird auch Zeichenkette oder String genannt.\n",
    "\n",
    "Texte haben wir auch schon gesehen, z.B.:\n",
    "\n",
    "* Variablennamen `a`, `b`, `c`\n",
    "* Funktionsnamen wie `my_min` und `cos`\n",
    "\n",
    "Um Texte, mit denen wir rechnen wollen, von Variablen und Funktionen zu unterscheiden, müssen wir diese in \" oder ' einschließen."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "id": "7ae417ae-c8d5-4f0e-a280-16265f3fa2d3",
   "metadata": {},
   "outputs": [],
   "source": [
    "a = 'Wort'\n",
    "b = \"Zwei Worte\"\n",
    "c = \"\"\"Ein mehrzeiliger Text\n",
    "muss in\n",
    "drei Hochkommatas\n",
    "eingeschlossen werden.\"\"\""
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "8af71ec8-1c40-4106-bbd4-3b0bdd2968f7",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Wort'"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "a"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "id": "14c7d057-124d-4e3b-b6be-a966687930e1",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Ein mehrzeiliger Text\\nmuss in\\ndrei Hochkommatas\\neingeschlossen werden.'"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "c"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "2e280d2d-eda2-473d-8997-94de82444f48",
   "metadata": {},
   "source": [
    "ℹ️ mit \\ lassen sich Sonderzeichen darstellen\n",
    "\n",
    "* \\\\ = \\\n",
    "* \\n = Zeilenumbruch\n",
    "* \\t = Tabulator"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "41dc4823-c5f0-4ffb-a6c6-c091789cf309",
   "metadata": {},
   "source": [
    "## Aufgabe\n",
    "❓ Was kann man alles mit Texten machen?\n",
    "\n",
    "Tipp:\n",
    "* `c.<TAB>`\n",
    "* `help(str)`"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "a376173a-66db-485f-acfe-818c44ad7320",
   "metadata": {},
   "source": [
    "## Lösung\n",
    "Die Aufgabe war so einfach, die braucht keine Lösung."
   ]
  },
  {
   "cell_type": "markdown",
   "id": "d6a2bb1b-120c-48bf-aed5-ec11fe83f50a",
   "metadata": {},
   "source": [
    "## Aufgabe\n",
    "❓ Schreibt eine Funktion, die als Parameter ein englisches Wort akzeptiert und dessen Pluralform zurückliefert."
   ]
  },
  {
   "cell_type": "markdown",
   "id": "59669fc1-2dc6-43a6-a297-3304f190d8ea",
   "metadata": {},
   "source": [
    "## Lösung\n",
    "Wir ignorieren die Sonderfälle und beschränken uns darauf, dBuchstaben **s** anzufügen wenn das Wort nicht damit endet."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "id": "45aa62f3-1257-4499-b2fb-b818cc1dbd21",
   "metadata": {},
   "outputs": [],
   "source": [
    "def plural(s):\n",
    "    if s.endswith('s'):\n",
    "        return s\n",
    "    else:\n",
    "        return s + 's'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "id": "ddfbc878-4c16-48a8-852c-97379f447ab9",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'horses'"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "plural(\"horse\")"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "0e1833b4-aa3b-41b4-9602-0e36103e0070",
   "metadata": {},
   "source": [
    "## Rechnen mit Texten\n",
    "Texte kann man addieren und multiplizieren:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "id": "17a904df-8ffc-467a-8744-e2a4fd8b2134",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Hallo   Python'"
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "a = \"Hallo\"\n",
    "b = \"Python\"\n",
    "a + '   ' + b"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "id": "8c7599a2-c199-433b-bc74-5da51688bdd1",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'HalloHalloHallo'"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "a * 3"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "854d1c91-d4ea-478f-822e-3a3736fb5ff3",
   "metadata": {},
   "source": [
    "Das kann man z.B. nutzen, um einen langen Strich zu erzeugen:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "id": "ef7ad859-36f3-46a4-9f5c-972eb45ad0e7",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'________________________________________________________________________________'"
      ]
     },
     "execution_count": 11,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "'_' * 80"
   ]
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 3 (ipykernel)",
   "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": "3.9.7"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 5
}