python 中删除指定行的数据
1、删除第1行
[root@PC1 test2]# ls a.txt test.py [root@PC1 test2]# cat a.txt 01 11 21 31 02 12 22 32 03 13 23 33 04 14 24 34 05 15 25 35 06 16 26 36 [root@PC1 test2]# cat test.py #!/usr/bin/python in_file = open("a.txt", "r") out_file = open("result.txt", "w") lines = in_file.readlines() lines = lines[1:] for i in lines: out_file.write(i) in_file.close() out_file.close() [root@PC1 test2]# python test.py [root@PC1 test2]# ls a.txt result.txt test.py [root@PC1 test2]# cat result.txt 02 12 22 32 03 13 23 33 04 14 24 34 05 15 25 35 06 16 26 36
2、删除第3行
[root@PC1 test2]# ls a.txt test.py [root@PC1 test2]# cat a.txt 01 11 21 31 02 12 22 32 03 13 23 33 04 14 24 34 05 15 25 35 06 16 26 36 [root@PC1 test2]# cat test.py #!/usr/bin/python in_file = open("a.txt", "r") out_file = open("result.txt", "w") lines = in_file.readlines() for i in range(0,len(lines)): if i == 2: continue out_file.write(lines[i]) in_file.close() out_file.close() [root@PC1 test2]# python test.py [root@PC1 test2]# ls a.txt result.txt test.py [root@PC1 test2]# cat result.txt 01 11 21 31 02 12 22 32 04 14 24 34 05 15 25 35 06 16 26 36
3、删除前三行
[root@PC1 test2]# ls a.txt test.py [root@PC1 test2]# cat a.txt 01 11 21 31 02 12 22 32 03 13 23 33 04 14 24 34 05 15 25 35 06 16 26 36 [root@PC1 test2]# cat test.py #!/usr/bin/python in_file = open("a.txt", "r") out_file = open("result.txt", "w") lines = in_file.readlines() lines = lines[3:] for i in lines: out_file.write(i) in_file.close() out_file.close() [root@PC1 test2]# python test.py [root@PC1 test2]# ls a.txt result.txt test.py [root@PC1 test2]# cat result.txt 04 14 24 34 05 15 25 35 06 16 26 36
4、删除最后一行
[root@PC1 test2]# ls a.txt test.py [root@PC1 test2]# cat a.txt 01 11 21 31 02 12 22 32 03 13 23 33 04 14 24 34 05 15 25 35 06 16 26 36 [root@PC1 test2]# cat test.py #!/usr/bin/python in_file = open("a.txt", "r") out_file = open("result.txt", "w") lines = in_file.readlines() lines = lines[:len(lines)-1] for i in lines: out_file.write(i) in_file.close() out_file.close() [root@PC1 test2]# python test.py [root@PC1 test2]# ls a.txt result.txt test.py [root@PC1 test2]# cat result.txt 01 11 21 31 02 12 22 32 03 13 23 33 04 14 24 34 05 15 25 35
5、删除倒数第2行
[root@PC1 test2]# ls a.txt test.py [root@PC1 test2]# cat a.txt 01 11 21 31 02 12 22 32 03 13 23 33 04 14 24 34 05 15 25 35 06 16 26 36 [root@PC1 test2]# cat test.py #!/usr/bin/python in_file = open("a.txt", "r") out_file = open("result.txt", "w") lines = in_file.readlines() for i in range(0, len(lines)): if i == (len(lines) - 1 - 1): continue out_file.write(lines[i]) in_file.close() out_file.close() [root@PC1 test2]# python test.py [root@PC1 test2]# ls a.txt result.txt test.py [root@PC1 test2]# cat result.txt 01 11 21 31 02 12 22 32 03 13 23 33 04 14 24 34 06 16 26 36
6、删除最后3行
[root@PC1 test2]# ls a.txt test.py [root@PC1 test2]# cat a.txt 01 11 21 31 02 12 22 32 03 13 23 33 04 14 24 34 05 15 25 35 06 16 26 36 [root@PC1 test2]# cat test.py #!/usr/bin/python in_file = open("a.txt", "r") out_file = open("result.txt", "w") lines = in_file.readlines() length = len(lines) - 3 lines = lines[:length] for i in lines: out_file.write(i) in_file.close() out_file.close() [root@PC1 test2]# python test.py [root@PC1 test2]# ls a.txt result.txt test.py [root@PC1 test2]# cat result.txt 01 11 21 31 02 12 22 32 03 13 23 33
