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2018-03-12から1日間の記事一覧

【Python】How to find the most frequent value in a numpy array? - 101 Numpy Exercises

Q: irisのpetal lengthで最も出現頻度が高い値を見つけなさい A: # Input: url = 'https://archive.ics.uci.edu/ml/machine-learning-databases/iris/iris.data' iris = np.genfromtxt(url, delimiter=',', dtype='object') # Solution: vals, counts = np.u…

【Python】How to sort a 2D array by a column? - 101 Numpy Exercises

Q: irisデータセットをsepallengthカラムの値でソートしなさい A: url = 'https://archive.ics.uci.edu/ml/machine-learning-databases/iris/iris.data' iris = np.genfromtxt(url, delimiter=',', dtype='object') names = ('sepallength', 'sepalwidth', '…

【Python】How to get the second largest value of an array when grouped by another array? - 101 Numpy Exercises

Q: setosaで二番目に長いpetallengthは何? # Input url = 'https://archive.ics.uci.edu/ml/machine-learning-databases/iris/iris.data' iris = np.genfromtxt(url, delimiter=',', dtype='object') names = ('sepallength', 'sepalwidth', 'petallength',…