{"cells":[{"metadata":{"_uuid":"8f2839f25d086af736a60e9eeb907d3b93b6e0e5","_cell_guid":"b1076dfc-b9ad-4769-8c92-a6c4dae69d19","trusted":true},"cell_type":"code","source":"import numpy as np # linear algebra\nimport pandas as pd # data processing, CSV file I/O (e.g. pd.read_csv)\nfrom sklearn.preprocessing import StandardScaler \nfrom sklearn.datasets import fetch_mldata\nfrom sklearn.model_selection import train_test_split # Aufteilung in Training und Test\nfrom sklearn.tree import DecisionTreeClassifier","execution_count":null,"outputs":[]},{"metadata":{"trusted":true,"_uuid":"50bee69c725c568229977d13cc44c25c20d8bc9b"},"cell_type":"code","source":"mnist = fetch_mldata('MNIST original') # images of hand written digits","execution_count":null,"outputs":[]},{"metadata":{"_cell_guid":"79c7e3d0-c299-4dcb-8224-4455121ee9b0","_uuid":"d629ff2d2480ee46fbb7e2d37f6b5fab8052498a","trusted":true},"cell_type":"code","source":"train_x, test_x, train_y, test_y = train_test_split( mnist.data, mnist.target, test_size=1/7.0, random_state=0)\n","execution_count":null,"outputs":[]},{"metadata":{"trusted":true,"_uuid":"bd1f5adc7e1683b223176bc6d413dfa6228bac47"},"cell_type":"code","source":"scaler = StandardScaler()\nscaler.fit(train_x)\ntrain_x = scaler.transform(train_x)\ntest_x = scaler.transform(test_x) \ntest_x_copy = test_x","execution_count":null,"outputs":[]},{"metadata":{"trusted":true,"_uuid":"23ab65f85d984305984be724fe11cc33c76060c9"},"cell_type":"code","source":"import matplotlib.pyplot as plt\nfirst_array=test_x_copy[0].reshape(28,28)\nplt.imshow(first_array)\nplt.show()","execution_count":null,"outputs":[]},{"metadata":{"trusted":true,"_uuid":"7afe76071a069833b29682d81a54eca4e957c1f7"},"cell_type":"code","source":"from sklearn.decomposition import PCA\npca = PCA(n_components=0.95)\npca.fit(train_x)\ntrain_x = pca.transform(train_x)\ntest_x = pca.transform(test_x)","execution_count":null,"outputs":[]},{"metadata":{"_uuid":"0034b2b81e0d75aa873ef7f7571fc34d2392a5c9"},"cell_type":"markdown","source":"## Criterion: gini"},{"metadata":{"trusted":true,"_uuid":"4f855f08e7e9ea64787c1963bb0eafb1af49e8bc"},"cell_type":"code","source":"model = DecisionTreeClassifier(criterion=\"gini\", max_depth=32)","execution_count":null,"outputs":[]},{"metadata":{"trusted":true,"_uuid":"8828ec0beaf4dd455b775b6694cd1c42968efdc0"},"cell_type":"code","source":"model.fit(train_x, train_y)","execution_count":null,"outputs":[]},{"metadata":{"trusted":true,"_uuid":"ae81c255d043c8c005014da8abc9da3bbd1d5608"},"cell_type":"code","source":"score = model.score(test_x, test_y)","execution_count":null,"outputs":[]},{"metadata":{"trusted":true,"_uuid":"145bfeed3ae4bec1755852a46d6d9264595ec569"},"cell_type":"code","source":"print(score)","execution_count":null,"outputs":[]},{"metadata":{"_uuid":"5e0576c2bf16f0fb4ec72bc39383febba55eeca6"},"cell_type":"markdown","source":"## Criterion: entropy"},{"metadata":{"trusted":true,"_uuid":"621751d26afd82e190d07db735f5f41de58a63cc"},"cell_type":"code","source":"model2 = DecisionTreeClassifier(criterion=\"entropy\", max_depth=32)\nmodel2.fit(train_x, train_y)\nscore = model2.score(test_x, test_y)\nprint(score)","execution_count":null,"outputs":[]}],"metadata":{"kernelspec":{"display_name":"Python 3","language":"python","name":"python3"},"language_info":{"name":"python","version":"3.6.6","mimetype":"text/x-python","codemirror_mode":{"name":"ipython","version":3},"pygments_lexer":"ipython3","nbconvert_exporter":"python","file_extension":".py"}},"nbformat":4,"nbformat_minor":1}