csv文件中列值的python完全匹配答案

【问题标题】：python exact match of column value in csv filescsv文件中列值的python完全匹配
【发布时间】：2015-01-29 15:24:06
【问题描述】：

我有一个包含多行和多列的 csv 文件。我想使用 python 3.4 过滤我的文件并创建一个与行中某些值完全匹配的新文件。我的问题是我选择 2 列来过滤行：如果 EQA nb 与列表中组织的确切名称匹配，则将该行复制到新文件中。

我的文件是这样的：

EQA_nb,organization,a,b,c,d
16,TCS,a1,b1,c1,d1
14,LS,a2,b2,c2,d2
14,BMC,a3,b3,c3,d3
2,TLS,a4,b4,c4,d4
6,LCHC,a5,b5,c5,d5
14,TLS,a6,b6,c6,d6
etc..

我的代码是：

import csv
with open ('data.csv','w',newline='') as outf, open('output.csv','r', newline='')as inf:
    reader = csv.DictReader(inf, delimiter=',')
    writer = csv.DictWriter(outf, fieldnames=reader.fieldnames, delimiter=',')
    writer.writeheader()

    for row in reader:
        if ((row["EQA_nb"]== '6' and row["organization"] in "EP, LCHC, SP")
                or (row["EQA_nb"]== "2" and row["organization"] in "AMC, LCHC, SGPLP, TCS, TLS")
                or (row["EQA_nb"]== "7" and row["organization"] in "GP")
                or (row["EQA_nb"]== "8" and row["organization"] in "LFMC")
                or (row["EQA_nb"]== "9" and row["organization"] in "LS")
                or (row["EQA_nb"]== "11" and row["organization"] in "DP, WSS")
                or (row["EQA_nb"]== "13" and row["organization"] in "TRP")
                or (row["EQA_nb"]== "14" and row["organization"] in "BMC,TLS")): 

            writer.writerow(row)

我希望新文件显示与指定的行值完全匹配，即显示 14 TLS 但不显示 14 LS，例如当前代码所示。感谢您的帮助！

【问题讨论】：

标签： python python-3.x csv

【解决方案1】：

替换

'BMC,TLS'

与

['BMP', 'TLS']

然后

row['organization'] in ['BMP', 'TLS']

将匹配“TLS”但不匹配“LS”。

【讨论】：

【解决方案2】：

这可以通过将匹配项放入字典中非常巧妙地完成，将 if/elif 链减少到单个查找，而这又可以使用operator.itemgetter 进行优化。

import csv
import operator


mapping = {
    "6": ["EP", "LCHC", "SP"],
    "2": ["AMC", "LCHC", "SGPLP", "TCS", "TLS"],
    "7": ["GP"],
    "8": ["LFMC"],
    "9": ["LS"],
    "11": ["DP", "WSS"],
    "13": ["TRP"],
    "14": ["BMC", "TLS"],
}


kv = operator.itemgetter("EQA_nb", "organization")


with open("data.csv", "w", newline="") as outf, open("output.csv", "r", newline="") as inf:
    reader = csv.DictReader(inf, delimiter=",")
    writer = csv.DictWriter(outf, fieldnames=reader.fieldnames, delimiter=",")
    writer.writeheader()

    for row in reader:
        eqa, org = kv(row)
        if org in mapping.get(eqa, []):
            writer.writerow(row)

【讨论】：