python 正則表達式搜索未在路徑中找到下划線

Question

我有一個遵循某種結構的長文件，我想解析這個文件以提取一個名為sample的 object：

名為paths_text.txt的文件是這樣的：

/groups/cgsd/javed/validation_set/LeungSY_Targeted_SS-190528-01a/Clean/pfg001G_1_Clean.fastq.gz
/groups/cgsd/javed/validation_set/LeungSY_Targeted_SS-190528-01a/Clean/pfg001G_2_Clean.fastq.gz
/groups/cgsd/javed/validation_set/LeungSY_Targeted_SS-190528-01a/Clean/pfg001T_1_Clean.fastq.gz
/groups/cgsd/javed/validation_set/LeungSY_Targeted_SS-190528-01a/Clean/pfg001T_2_Clean.fastq.gz

我的代碼運行良好，如下所示：

import os
os.chdir('/groups/cgsd/alexandre/python_code')
import re


with open('./src/paths_text.txt') as f:
    for line in f:
        sample = re.search(r'pfg\d+',line)
        print(sample)

但是當我搜索下划線時，我的匹配結果是None ，為什么？

import os
os.chdir('/groups/cgsd/alexandre/python_code')
import re


with open('./src/paths_text.txt') as f:
    for line in f:
        sample = re.search(r'pfg\d+_',line)
        print(sample)

Answer 1

因為pfg001和_之間有G和T 。 \d+只計算數字。