Sample Code/Day_03_SampleCode_v2.ipynb

{"nbformat":4,"nbformat_minor":0,"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":"3.6.5"},"colab":{"name":"03 Example_維元.ipynb","provenance":[]}},"cells":[{"cell_type":"markdown","metadata":{"id":"XZ5H6uQv1Oo3"},"source":["# 範例\n","***"]},{"cell_type":"markdown","metadata":{"id":"O9XVaI1E1OpA"},"source":["# [教學目標]\n","\n","* 能夠使用不同的方法初始化一個陣列\n","* 知道固定大小對於陣列的意義\n","* 了解不同的亂數陣列有什麼差異\n","\n"]},{"cell_type":"code","metadata":{"id":"Z6Hj66lj1OpB","outputId":"d5f18872-c671-43cb-a586-e216ca651d40"},"source":["# 載入 NumPy 套件\n","import numpy as np\n","\n","# 檢查正確載入與版本\n","print(np)\n","print(np.__version__)"],"execution_count":null,"outputs":[{"output_type":"stream","text":["<module 'numpy' from '/Users/wei/.virtualenvs/py3/lib/python3.6/site-packages/numpy/__init__.py'>\n","1.16.1\n"],"name":"stdout"}]},{"cell_type":"code","metadata":{"id":"77SyjUq01OpD","outputId":"213fca59-8031-4c2f-e9aa-a5c21a69c950"},"source":["# 內建型態做轉換\n","\n","import numpy as np\n","\n","np.array([1, 2, 3])"],"execution_count":null,"outputs":[{"output_type":"execute_result","data":{"text/plain":["array([1, 2, 3])"]},"metadata":{"tags":[]},"execution_count":2}]},{"cell_type":"code","metadata":{"id":"CAVhCEsw1OpE","outputId":"916cef03-6066-4d18-afb2-8e683b80ff13"},"source":["# 會自動轉換成範圍比較大的型態：\n","\n","print(np.array([1, 2, 3.0]), np.array([1, 2, 3.0]).dtype)\n","\n","# 也可以指定成想要的型態：\n","\n","print(np.array([1, 2, 3], dtype=complex), np.array([1, 2, 3], dtype=complex).dtype)"],"execution_count":null,"outputs":[{"output_type":"stream","text":["[1. 2. 3.] float64\n","[1.+0.j 2.+0.j 3.+0.j] complex128\n"],"name":"stdout"}]},{"cell_type":"code","metadata":{"id":"qGssWBdQ1OpE","outputId":"4be02555-56ad-474d-ed02-ae3aa624ae78"},"source":["# 字典型態被轉成陣列不符合期待\n","\n","print(np.array({0: 123, 1: 456}))\n","print(np.array({0: 123, 1: 456}).size)\n","\n","# 正確的寫法應該寫轉成有序的 List 再作轉換\n","\n","print(np.array(list({0: 123, 1: 456}.items())))\n","print(np.array(list({0: 123, 1: 456}.items())).size)"],"execution_count":null,"outputs":[{"output_type":"stream","text":["{0: 123, 1: 456}\n","1\n","[[  0 123]\n"," [  1 456]]\n","4\n"],"name":"stdout"}]},{"cell_type":"code","metadata":{"id":"fAYl6c3o1OpE","outputId":"3b2ed56b-7a05-4856-ef75-cdb3750d5fc5"},"source":["# 從固定大小的初始值開始\n","\n","print(np.zeros((2, 3)))\n","print(np.ones((2, 3)))\n","print(np.full((2, 3), 9))\n"],"execution_count":null,"outputs":[{"output_type":"stream","text":["[[0. 0. 0.]\n"," [0. 0. 0.]]\n","[[1. 1. 1.]\n"," [1. 1. 1.]]\n","[[9 9 9]\n"," [9 9 9]]\n"],"name":"stdout"}]},{"cell_type":"code","metadata":{"id":"YdUe_4e51OpF","outputId":"52c071cf-46eb-4b35-9cb5-6d010f7bf6f5"},"source":["# np.zeros 和 np.empty \n","\n","print(np.zeros((2, 3)))\n","print(np.empty((2, 3)))\n"],"execution_count":null,"outputs":[{"output_type":"stream","text":["[[0. 0. 0.]\n"," [0. 0. 0.]]\n","[[0. 0. 0.]\n"," [0. 0. 0.]]\n"],"name":"stdout"}]},{"cell_type":"code","metadata":{"id":"oYx_QqYi1OpG","outputId":"275964be-4c8b-41d8-b052-3d2d69adf4b5"},"source":["# 從固定大小的序列值開始\n","\n","print(np.arange( 10, 30, 5 ))\n","print(np.linspace( 0, 2, 3 ))\n","print(np.logspace( 0, 2, 3 ))\n"],"execution_count":null,"outputs":[{"output_type":"stream","text":["[10 15 20 25]\n","[0. 1. 2.]\n","[  1.  10. 100.]\n"],"name":"stdout"}]},{"cell_type":"code","metadata":{"id":"pX77QLqn1OpG","outputId":"7047e4a8-b304-47c8-a0f2-ec05090af392"},"source":["## 從固定大小的亂數值開始（新版）\n","\n","from numpy.random import default_rng\n","rng = default_rng()\n","\n","normal = rng.standard_normal((3,2))\n","random = rng.random((3,2))\n","integers = rng.integers(0, 10, size=(3,2))\n","\n","print(normal)\n","print(random)\n","print(integers)"],"execution_count":null,"outputs":[{"output_type":"stream","text":["[[-0.24474896 -1.33770124 -0.10670728]\n"," [ 1.04809472 -1.48783473 -2.59464583]]\n","[[0.11597017 0.69626   ]\n"," [0.19672026 0.90570296]\n"," [0.38300972 0.37025436]]\n","[[0 8]\n"," [7 6]\n"," [7 3]]\n"],"name":"stdout"}]},{"cell_type":"code","metadata":{"id":"ReTrub901OpH","outputId":"7a10f7b7-5080-4732-f598-0ee70fb21a9d"},"source":["## 從固定大小的亂數值開始（舊版）\n","\n","normal = np.random.randn(2, 3)\n","random = np.random.random((3,2))\n","integers = np.random.randint(0, 10, size=(3,2))\n","\n","print(normal)\n","print(random)\n","print(integers)"],"execution_count":null,"outputs":[{"output_type":"stream","text":["[[-0.85696769 -0.03929064 -0.43855898]\n"," [ 0.77037149 -0.51963871 -0.25234342]]\n","[[0.05117243 0.44764696]\n"," [0.35231559 0.60465553]\n"," [0.38218634 0.72874085]]\n","[[7 2]\n"," [2 9]\n"," [5 5]]\n"],"name":"stdout"}]},{"cell_type":"code","metadata":{"id":"LOe1HrKf1OpH"},"source":[""],"execution_count":null,"outputs":[]},{"cell_type":"code","metadata":{"id":"7_VHGN_r1OpH"},"source":[""],"execution_count":null,"outputs":[]}]}