Solution/Day_03_Solution_v2.ipynb

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    "# [作業目標]\n",
    "\n",
    "1. [簡答題] 請比較 np.zeros 和 np.empty 產生出來的陣列有何差異？為什麼要設計兩種方法？\n",
    "\n",
    "```\n",
    "print(np.zeros((2, 3)))\n",
    "print(np.empty((2, 3)))\n",
    "```\n",
    "\n",
    "2. 在不用「整數亂數方法」的限制下，如何將包含小數的轉換整數？請將給定的 a 陣列當中的元素變成去掉小數變成整數。\n",
    "3. 承上題，怎樣可以限制整數的範圍介於 m - n 之間？請將給定的 a 陣列當中的元素的範圍調整成 m - n 之間。"
   ]
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   "source": [
    "# 作業 "
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### 1. [簡答題] 請比較 np.zeros 和 np.empty 產生出來的陣列有何差異？為什麼要設計兩種方法？\n",
    "\n",
    "```\n",
    "print(np.zeros((2, 3)))\n",
    "print(np.empty((2, 3)))\n",
    "```\n"
   ]
  },
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    {
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      "text/plain": [
       "'\\nnp.zeros((2, 3)) 會產生真正的 0；np.empty((2, 3)) 會產生一個近似於 0 的陣列。\\nnp.empty 可以用於只是想要初始化，但之後就會數值覆寫過的形況。\\n'"
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   "source": [
    "'''\n",
    "np.zeros((2, 3)) 會產生真正的 0；np.empty((2, 3)) 會產生一個近似於 0 的陣列。\n",
    "np.empty 可以用於只是想要初始化，但之後就會數值覆寫過的形況。\n",
    "'''"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### 2. 在不用「整數亂數方法」的限制下，如何將包含小數的轉換整數？請將給定的 a 陣列當中的元素變成去掉小數變成整數。\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[[53.34798531 86.50474634  5.46029513]\n",
      " [11.30568258 17.24004009 99.67331458]]\n"
     ]
    }
   ],
   "source": [
    "# 記得先 Import 正確的套件\n",
    "\n",
    "import numpy as np\n",
    "\n",
    "a = np.random.rand(2, 3)\n",
    "a = a * 100\n",
    "\n",
    "print(a)"
   ]
  },
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   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "colab": {},
    "colab_type": "code",
    "id": "e1gVI0tvsvFY"
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   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "[[ 53.  87.   5.]\n",
      " [ 11.  17. 100.]]\n",
      "[[ 53.  87.   5.]\n",
      " [ 11.  17. 100.]]\n"
     ]
    }
   ],
   "source": [
    "# 參考解答\n",
    "\n",
    "print(a.round())\n",
    "print(np.round(a))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### 3. 承上題，怎樣可以限制整數的範圍介於 m - n 之間？請將給定的 a 陣列當中的元素的範圍調整成 m - n 之間。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[[29. 23. 39.]\n",
      " [34. 39. 37.]]\n"
     ]
    }
   ],
   "source": [
    "m = 20\n",
    "n = 40\n",
    "\n",
    "a = np.random.rand(2, 3) * (n - m)\n",
    "b = a\n",
    "\n",
    "print((a - b % 1) + m)"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
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   "cell_type": "code",
   "execution_count": null,
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   "source": []
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