python中使用lines = [line for line in file (file name)]的格式是列表推导式，这个等式是将for循环的结果存储到列表lines中。列表推导式（又称列表解析式）提供了一种简明扼要的方法来创建列表，它是利用其创建新列表list的一个简单方法。列表推导式比较像for循环语句，必要时也可以加入if条件语句完善...
with open('data.txt', 'r') as file: lines = [line.strip() for line in file if 'python' in line.lower()] ``` 组合逻辑和条件判断: ```python # 使用嵌套循环生成所有可能的组合 combinations = [(x, y) for x in ['A', 'B', 'C'] for y in ['X', 'Y']] print(combinations...
可以同时使用多个嵌套的for循环并对每个循环使用if条件表达式,语法如下: [ i_1,i_2,...,i_n运算表达式 for i_1 in iter1 if 条件表达式1 for i_2 in iter2 if 条件表达式2 ... for i_n in itern if 条件表达式n ] 1. 2. 3. 4. 以上语法大致相当于如下等价代码: s = [] for i_1 in ...
#将文件读进列表(反复追加)中: lines = [] with open("test001.txt","r") as y: for line in y: lines.append(line) y.close() #在列表中插入文本数据: lines.insert(0, "aaaa\n") lines.insert(1, "bbbb\n") print(lines) #利用分隔符连接: s = ''.join(lines) print(s) #写到文件中...
File: loop1.py 1 2 3 for i in range(5): print("The value of i is", i) print("The loop has ended.") python3 loop1.py The value of i is 0 The value of i is 1 The value of i is 2 The value of i is 3 The value of i is 4 The loop has ended. In the next ex...
self.total_lines = 0 # 总代码行数 self.comment_lines = 0 # 纯注释行数 self.blank_lines = 0 # 空白行数 self.effective_lines = 0 # 有效代码行数(非空白、非纯注释),其实可以 有效代码行数=总代码行数-纯注释行数-空白行数 self.effective_lines_total_length = 0 # 有效代码行的总长度 sel...
"""defmain():# file 文件类型的对象# 1.txt 的编码方式是 utf-8withopen(r'1.txt', encoding="utf-8")asfile:# 显示文件指针print(file.tell())# 这句话会改变文件的指针lines =list(file)print(lines)# 显示文件指针print(file.tell())print()# 这句话 非加不可。为啥呀?# 因为在lines=list...
We’re thrilled to announce the alpha release of our new open-source Python driver for Microsoft SQL Server and the Azure SQL family, now available on GitHub at mssql-python. Feb 6, 2025 Post comments count0 Post likes count1 Python in Visual Studio Code – February 2025 Release ...
ENDDO. *新语法 x未表达式中隐式定义的变量 DATA(gt_lines2) = VALUE ty_t_line( FOR x = 1 THEN x + 1 UNTIL x > 10 ( a = x b = x + 1 c = x + 2 ) ). -TAB 热爱技术 享受生活 本文参与 腾讯云自媒体同步曝光计划,分享自微信公众号。 原始发表:2019-12-05,如有侵权请联系 cloudco...
gci.py - Interface to Python's built-in garbage collector gh.py - GitHub interface git.py - Git client ported from shellista grep.py - search contents of file(s) head.py - Display first lines of a file httpserver.py - A simple HTTP server with upload function (ripped from https://...