Cap04-05-Funcao-Map.ipynb

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   "metadata": {},
   "source": [
    "# <font color='blue'>Python Fundamentos - Capítulo 4</font>\n",
    "\n",
    "## Programação Funcional com map()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Versão da Linguagem Python Usada Neste Jupyter Notebook: 3.7.6\n"
     ]
    }
   ],
   "source": [
    "# Versão da Linguagem Python\n",
    "from platform import python_version\n",
    "print('Versão da Linguagem Python Usada Neste Jupyter Notebook:', python_version())"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Map - aplica uma função a todos os elementos da sequência"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Criando duas funções\n",
    "\n",
    "# Função 1 - Recebe uma temperatura como parâmetro e retorna a temperatura em Fahrenheit\n",
    "def fahrenheit(T):\n",
    "    return ((float(9)/5)*T + 32)\n",
    "\n",
    "# Função 2 - Recebe uma temperatura como parâmetro e retorna a temperatura em Celsius\n",
    "def celsius(T):\n",
    "    return (float(5)/9)*(T-32)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Criando uma lista\n",
    "temperaturas = [0, 22.5, 40, 100]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<map at 0x111b6a2d0>"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Aplicando a função a cada elemento da lista de temperaturas. \n",
    "# Em Python 3, a funçãp map() retornar um iterator\n",
    "map(fahrenheit, temperaturas)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[32.0, 72.5, 104.0, 212.0]"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Converter p/ lista para retornar os resultados de map()\n",
    "# Função map() retornando a lista de temperaturas convertidas em Fahrenheit\n",
    "list(map(fahrenheit, temperaturas))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "32.0\n",
      "72.5\n",
      "104.0\n",
      "212.0\n"
     ]
    }
   ],
   "source": [
    "# Usando um loop for para imprimir o resultado da função map()\n",
    "for temp in map(fahrenheit, temperaturas):\n",
    "    print(temp)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<map at 0x111b823d0>"
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Convertendo para Celsius\n",
    "map(celsius, temperaturas)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[-17.77777777777778, -5.277777777777778, 4.444444444444445, 37.77777777777778]"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "list(map(celsius, temperaturas))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<map at 0x111b00450>"
      ]
     },
     "execution_count": 9,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Usando lambda\n",
    "map(lambda x: (5.0/9)*(x - 32), temperaturas)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[-17.77777777777778, -5.277777777777778, 4.444444444444445, 37.77777777777778]"
      ]
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     "execution_count": 10,
     "metadata": {},
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   ],
   "source": [
    "list(map(lambda x: (5.0/9)*(x - 32), temperaturas))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Somando os elementos de 2 listas\n",
    "a = [1,2,3,4]\n",
    "b = [5,6,7,8]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[6, 8, 10, 12]"
      ]
     },
     "execution_count": 12,
     "metadata": {},
     "output_type": "execute_result"
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   ],
   "source": [
    "list(map(lambda x,y:x+y, a, b))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Somando os elementos de 3 listas\n",
    "a = [1,2,3,4]\n",
    "b = [5,6,7,8]\n",
    "c = [9,10,11,12]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[15, 18, 21, 24]"
      ]
     },
     "execution_count": 14,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "list(map(lambda x,y,z:x+y+z, a, b, c))"
   ]
  }
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