{"id":1037308,"date":"2024-12-31T12:14:03","date_gmt":"2024-12-31T04:14:03","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/1037308.html"},"modified":"2024-12-31T12:14:05","modified_gmt":"2024-12-31T04:14:05","slug":"%e7%94%a8python%e5%a6%82%e4%bd%95%e5%8f%96%e7%9f%a9%e9%98%b5%e7%9a%84%e5%ad%90%e7%9f%a9%e9%98%b5","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/1037308.html","title":{"rendered":"\u7528python\u5982\u4f55\u53d6\u77e9\u9635\u7684\u5b50\u77e9\u9635"},"content":{"rendered":"

\"\u7528python\u5982\u4f55\u53d6\u77e9\u9635\u7684\u5b50\u77e9\u9635\"<\/p>\n

\u5728Python\u4e2d\uff0c\u53ef\u4ee5\u901a\u8fc7\u4f7f\u7528Numpy\u5e93\u6765\u65b9\u4fbf\u5730\u63d0\u53d6\u77e9\u9635\u7684\u5b50\u77e9\u9635\u3002\u5e38\u7528\u7684\u65b9\u6cd5\u5305\u62ec\u5229\u7528\u5207\u7247\u64cd\u4f5c\u3001\u5e03\u5c14\u7d22\u5f15\u3001\u4ee5\u53ca\u82b1\u5f0f\u7d22\u5f15\u3002<\/strong><\/p>\n<\/p>\n

\u5229\u7528\u5207\u7247\u64cd\u4f5c\u662f\u6700\u5e38\u89c1\u4e14\u7b80\u4fbf\u7684\u65b9\u6cd5\uff0c\u9002\u7528\u4e8e\u9700\u8981\u63d0\u53d6\u8fde\u7eed\u533a\u57df\u7684\u5b50\u77e9\u9635\u3002\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u6307\u5b9a\u884c\u548c\u5217\u7684\u8303\u56f4\u6765\u83b7\u53d6\u5b50\u77e9\u9635\u3002\u4f8b\u5982\uff0c\u5982\u679c\u6211\u4eec\u6709\u4e00\u4e2a\u77e9\u9635A\uff0c\u9700\u8981\u63d0\u53d6\u4ece\u7b2c2\u884c\u5230\u7b2c4\u884c\u3001\u7b2c3\u5217\u5230\u7b2c5\u5217\u7684\u5b50\u77e9\u9635\uff0c\u53ef\u4ee5\u4f7f\u7528A[1:4, 2:5]\u6765\u5b9e\u73b0\u3002\u8be6\u7ec6\u63cf\u8ff0\u5982\u4e0b\uff1a<\/p>\n<\/p>\n

\u9996\u5148\uff0c\u6211\u4eec\u9700\u8981\u5b89\u88c5\u5e76\u5bfc\u5165Numpy\u5e93\uff1a<\/p>\n<\/p>\n

import numpy as np<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u77e9\u9635A\uff1a<\/p>\n<\/p>\n
A = np.array([[1, 2, 3, 4, 5],<\/p>\n
              [6, 7, 8, 9, 10],<\/p>\n
              [11, 12, 13, 14, 15],<\/p>\n
              [16, 17, 18, 19, 20],<\/p>\n
              [21, 22, 23, 24, 25]])<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u6211\u4eec\u60f3\u8981\u63d0\u53d6\u4ece\u7b2c2\u884c\u5230\u7b2c4\u884c\u3001\u7b2c3\u5217\u5230\u7b2c5\u5217\u7684\u5b50\u77e9\u9635\uff1a<\/p>\n<\/p>\n
sub_matrix = A[1:4, 2:5]<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[[ 8  9 10]<\/p>\n
 [13 14 15]<\/p>\n
 [18 19 20]]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u4e0b\u9762\u6211\u4eec\u5c06\u8be6\u7ec6\u63a2\u8ba8\u5404\u79cd\u65b9\u6cd5\uff0c\u5305\u62ec\u5207\u7247\u64cd\u4f5c\u3001\u5e03\u5c14\u7d22\u5f15\u3001\u4ee5\u53ca\u82b1\u5f0f\u7d22\u5f15\u6765\u63d0\u53d6\u5b50\u77e9\u9635\u3002<\/p>\n<\/p>\n
\u4e00\u3001\u5207\u7247\u64cd\u4f5c<\/h3>\n<\/p>\n
\u5207\u7247\u64cd\u4f5c\u662f\u6700\u5e38\u89c1\u4e14\u7b80\u4fbf\u7684\u65b9\u6cd5\uff0c\u9002\u7528\u4e8e\u9700\u8981\u63d0\u53d6\u8fde\u7eed\u533a\u57df\u7684\u5b50\u77e9\u9635\u3002<\/p>\n<\/p>\n
1.1 \u57fa\u672c\u5207\u7247<\/h4>\n<\/p>\n
\u5728Numpy\u4e2d\uff0c\u5207\u7247\u64cd\u4f5c\u53ef\u4ee5\u901a\u8fc7:<\/code>\u6765\u6307\u5b9a\u884c\u548c\u5217\u7684\u8303\u56f4\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
A = np.array([[1, 2, 3, 4, 5],<\/p>\n
              [6, 7, 8, 9, 10],<\/p>\n
              [11, 12, 13, 14, 15],<\/p>\n
              [16, 17, 18, 19, 20],<\/p>\n
              [21, 22, 23, 24, 25]])<\/p>\n
sub_matrix = A[1:4, 2:5]<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[[ 8  9 10]<\/p>\n
 [13 14 15]<\/p>\n
 [18 19 20]]<\/p>\n
<\/code><\/pre>\n<\/p>\n
1.2 \u4f7f\u7528\u6b65\u957f<\/h4>\n<\/p>\n
\u6211\u4eec\u8fd8\u53ef\u4ee5\u5728\u5207\u7247\u64cd\u4f5c\u4e2d\u4f7f\u7528\u6b65\u957f\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
sub_matrix = A[::2, ::2]<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[[ 1  3  5]<\/p>\n
 [11 13 15]<\/p>\n
 [21 23 25]]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u91cc\u6211\u4eec\u9009\u53d6\u4e86\u6bcf\u9694\u4e00\u884c\u548c\u4e00\u5217\u7684\u5143\u7d20\u3002<\/p>\n<\/p>\n
\u4e8c\u3001\u5e03\u5c14\u7d22\u5f15<\/h3>\n<\/p>\n
\u5e03\u5c14\u7d22\u5f15\u53ef\u4ee5\u7528\u6765\u63d0\u53d6\u77e9\u9635\u4e2d\u7279\u5b9a\u6761\u4ef6\u4e0b\u7684\u5143\u7d20\u3002\u5047\u8bbe\u6211\u4eec\u5e0c\u671b\u63d0\u53d6\u77e9\u9635\u4e2d\u6240\u6709\u5927\u4e8e10\u7684\u5143\u7d20\uff1a<\/p>\n<\/p>\n
sub_matrix = A[A > 10]<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[11 12 13 14 15 16 17 18 19 20 21 22 23 24 25]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5e03\u5c14\u7d22\u5f15\u8fd4\u56de\u7684\u662f\u4e00\u4e2a\u4e00\u7ef4\u6570\u7ec4\u3002\u5982\u679c\u9700\u8981\u4fdd\u7559\u539f\u59cb\u77e9\u9635\u7684\u5f62\u72b6\uff0c\u53ef\u4ee5\u4f7f\u7528np.where<\/code>\u51fd\u6570\uff1a<\/p>\n<\/p>\n
rows, cols = np.where(A > 10)<\/p>\n
sub_matrix = A[rows, cols]<\/p>\n
sub_matrix = sub_matrix.reshape((5, 3))<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[[11 12 13]<\/p>\n
 [14 15 16]<\/p>\n
 [17 18 19]<\/p>\n
 [20 21 22]<\/p>\n
 [23 24 25]]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u4e09\u3001\u82b1\u5f0f\u7d22\u5f15<\/h3>\n<\/p>\n
\u82b1\u5f0f\u7d22\u5f15\u53ef\u4ee5\u7528\u6765\u9009\u62e9\u4e0d\u8fde\u7eed\u7684\u884c\u548c\u5217\u3002\u5047\u8bbe\u6211\u4eec\u5e0c\u671b\u63d0\u53d6\u7b2c1\u30013\u548c5\u884c\uff0c\u7b2c2\u548c4\u5217\u7684\u5b50\u77e9\u9635\uff1a<\/p>\n<\/p>\n
rows = [0, 2, 4]<\/p>\n
cols = [1, 3]<\/p>\n
sub_matrix = A[np.ix_(rows, cols)]<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[[ 2  4]<\/p>\n
 [12 14]<\/p>\n
 [22 24]]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u82b1\u5f0f\u7d22\u5f15\u901a\u8fc7np.ix_<\/code>\u51fd\u6570\u521b\u5efa\u7d22\u5f15\u6570\u7ec4\uff0c\u4ece\u800c\u63d0\u53d6\u6307\u5b9a\u884c\u548c\u5217\u7684\u5b50\u77e9\u9635\u3002<\/p>\n<\/p>\n
\u56db\u3001\u4f7f\u7528\u51fd\u6570\u63d0\u53d6\u5b50\u77e9\u9635<\/h3>\n<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u5b9a\u4e49\u4e00\u4e2a\u51fd\u6570\u6765\u63d0\u53d6\u4efb\u610f\u5b50\u77e9\u9635\u3002\u8fd9\u4e2a\u51fd\u6570\u53ef\u4ee5\u63a5\u53d7\u77e9\u9635\u548c\u884c\u5217\u8303\u56f4\u4f5c\u4e3a\u53c2\u6570\uff0c\u5e76\u8fd4\u56de\u76f8\u5e94\u7684\u5b50\u77e9\u9635\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
def get_sub_matrix(matrix, row_start, row_end, col_start, col_end):<\/p>\n
    return matrix[row_start:row_end, col_start:col_end]<\/p>\n
sub_matrix = get_sub_matrix(A, 1, 4, 2, 5)<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[[ 8  9 10]<\/p>\n
 [13 14 15]<\/p>\n
 [18 19 20]]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u901a\u8fc7\u8fd9\u79cd\u65b9\u5f0f\uff0c\u6211\u4eec\u53ef\u4ee5\u66f4\u7075\u6d3b\u5730\u63d0\u53d6\u5b50\u77e9\u9635\u3002<\/p>\n<\/p>\n
\u4e94\u3001\u66f4\u591a\u9ad8\u7ea7\u64cd\u4f5c<\/h3>\n<\/p>\n
5.1 \u4f7f\u7528\u6761\u4ef6\u63d0\u53d6<\/h4>\n<\/p>\n
\u9664\u4e86\u57fa\u672c\u7684\u5e03\u5c14\u7d22\u5f15\uff0c\u6211\u4eec\u8fd8\u53ef\u4ee5\u4f7f\u7528\u590d\u6742\u7684\u6761\u4ef6\u63d0\u53d6\u3002\u4f8b\u5982\uff0c\u63d0\u53d6\u5076\u6570\u5143\u7d20\u7ec4\u6210\u7684\u5b50\u77e9\u9635\uff1a<\/p>\n<\/p>\n
sub_matrix = A[A % 2 == 0]<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[ 2  4  6  8 10 12 14 16 18 20 22 24]<\/p>\n
<\/code><\/pre>\n<\/p>\n
5.2 \u4f7f\u7528\u63a9\u7801<\/h4>\n<\/p>\n
\u63a9\u7801\u4e5f\u662f\u4e00\u79cd\u63d0\u53d6\u5b50\u77e9\u9635\u7684\u6709\u6548\u65b9\u6cd5\u3002\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u521b\u5efa\u4e00\u4e2a\u5e03\u5c14\u63a9\u7801\u6765\u9009\u62e9\u77e9\u9635\u4e2d\u7684\u7279\u5b9a\u5143\u7d20\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
mask = (A > 10) & (A < 20)<\/p>\n
sub_matrix = A[mask]<\/p>\n
print(sub_matrix)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8f93\u51fa\u5c06\u4f1a\u662f\uff1a<\/p>\n<\/p>\n
[11 12 13 14 15 16 17 18 19]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u901a\u8fc7\u4f7f\u7528\u63a9\u7801\uff0c\u6211\u4eec\u53ef\u4ee5\u66f4\u7075\u6d3b\u5730\u63d0\u53d6\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u7684\u5143\u7d20\u3002<\/p>\n<\/p>\n
\u516d\u3001\u603b\u7ed3<\/h3>\n<\/p>\n
\u5728Python\u4e2d\uff0c\u901a\u8fc7Numpy\u5e93\u53ef\u4ee5\u975e\u5e38\u65b9\u4fbf\u5730\u63d0\u53d6\u77e9\u9635\u7684\u5b50\u77e9\u9635\u3002\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u5207\u7247\u64cd\u4f5c\u3001\u5e03\u5c14\u7d22\u5f15\u3001\u82b1\u5f0f\u7d22\u5f15\u3001\u4ee5\u53ca\u63a9\u7801\u7b49\u591a\u79cd\u65b9\u6cd5\u6765\u5b9e\u73b0\u8fd9\u4e00\u76ee\u7684\u3002\u5207\u7247\u64cd\u4f5c\u662f\u6700\u5e38\u89c1\u4e14\u7b80\u4fbf\u7684\u65b9\u6cd5\uff0c\u9002\u7528\u4e8e\u63d0\u53d6\u8fde\u7eed\u533a\u57df\u7684\u5b50\u77e9\u9635\u3002\u5e03\u5c14\u7d22\u5f15\u548c\u63a9\u7801\u5219\u9002\u7528\u4e8e\u63d0\u53d6\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u7684\u5143\u7d20\uff0c\u800c\u82b1\u5f0f\u7d22\u5f15\u9002\u7528\u4e8e\u63d0\u53d6\u4e0d\u8fde\u7eed\u7684\u884c\u548c\u5217\u3002\u901a\u8fc7\u7075\u6d3b\u8fd0\u7528\u8fd9\u4e9b\u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u9ad8\u6548\u5730\u5904\u7406\u548c\u5206\u6790\u77e9\u9635\u6570\u636e\u3002<\/p>\n<\/p>\n
\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
 \u5982\u4f55\u4f7f\u7528Python\u63d0\u53d6\u77e9\u9635\u7684\u7279\u5b9a\u533a\u57df\uff1f<\/strong>
\u8981\u63d0\u53d6\u77e9\u9635\u7684\u7279\u5b9a\u533a\u57df\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528NumPy\u5e93\u3002\u9996\u5148\uff0c\u60a8\u9700\u8981\u5b89\u88c5NumPy\u5e93\u5e76\u5bfc\u5165\u5b83\u3002\u7136\u540e\uff0c\u60a8\u53ef\u4ee5\u901a\u8fc7\u5207\u7247\u64cd\u4f5c\u9009\u62e9\u6240\u9700\u7684\u884c\u548c\u5217\u3002\u4f8b\u5982\uff0csub_matrix = matrix[start_row:end_row, start_col:end_col]<\/code>\u53ef\u4ee5\u63d0\u53d6\u4ecestart_row<\/code>\u5230end_row<\/code>\u548cstart_col<\/code>\u5230end_col<\/code>\u7684\u5b50\u77e9\u9635\u3002<\/p>\n
\u5728Python\u4e2d\uff0c\u5982\u4f55\u5904\u7406\u4e8c\u7ef4\u5217\u8868\u4ee5\u83b7\u5f97\u5b50\u77e9\u9635\uff1f<\/strong>
\u5982\u679c\u60a8\u4f7f\u7528\u7684\u662f\u4e8c\u7ef4\u5217\u8868\u800c\u975eNumPy\u6570\u7ec4\uff0c\u53ef\u4ee5\u901a\u8fc7\u5217\u8868\u63a8\u5bfc\u5f0f\u6765\u5b9e\u73b0\u3002\u4f8b\u5982\uff0c\u4f7f\u7528sub_matrix = [row[start_col:end_col] for row in matrix[start_row:end_row]]<\/code>\u5c06\u5e2e\u52a9\u60a8\u83b7\u53d6\u5b50\u77e9\u9635\u3002\u8fd9\u79cd\u65b9\u6cd5\u7b80\u6d01\u660e\u4e86\uff0c\u9002\u7528\u4e8e\u5c0f\u578b\u77e9\u9635\u7684\u64cd\u4f5c\u3002<\/p>\n
\u6709\u6ca1\u6709\u5176\u4ed6\u5e93\u53ef\u4ee5\u7528\u4e8e\u63d0\u53d6\u77e9\u9635\u7684\u5b50\u77e9\u9635\uff1f<\/strong>
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