Python倒排索引函數

場景：輸入一個矩陣，返回倒排索引後的矩陣。矩陣值是連續的，需要分箱。

def genInvertedIndex(X, bin_len=0.1):
    # parameter: X ,numpy array (n*m)
    # bin_len, float, discretize the continuous value with bins
    # output: X_i, numpy array (w*n), w is the length of bins
    con_values = sorted(list(set(X.flatten().tolist())))
    bins = con_values#np.arange(con_values[0],con_values[-1],bin_len)
    X_i = np.zeros((len(bins)+1,X.shape[0]+1))
    for i in range(X.shape[0]):
        for val in X[i].tolist():
            X_i[np.digitize(val,bins),i]=1
    return X_i

測試代碼： 

X = np.array(X)
print(X)
X_i = genInvertedIndex(X)
print(X_i)

結果：

[[-0.355 -0.36  -0.375 ... -0.17  -0.17  -0.165]
 [-0.09  -0.06  -0.005 ... -0.12  -0.1   -0.1  ]
 [-0.085 -0.105 -0.14  ... -0.315 -0.325 -0.33 ]
 ...
 [-0.485 -0.38  -0.25  ... -0.425 -0.43  -0.44 ]
 [-0.085 -0.105 -0.13  ... -0.38  -0.38  -0.355]
 [-0.405 -0.395 -0.4   ... -0.415 -0.41  -0.38 ]]
[[0. 0. 0. ... 0. 0. 0.]
 [0. 0. 0. ... 0. 0. 0.]
 [0. 0. 0. ... 0. 1. 0.]
 ...
 [0. 0. 0. ... 0. 0. 0.]
 [0. 0. 0. ... 0. 0. 0.]
 [0. 0. 0. ... 0. 0. 0.]]