Python 2.7 使用python将csv文件的一行中的列中的值与下一行中的值进行比较

我一直在阅读csv.reader next，但没有找到一种方法将列中的值从一行比较到下一行。例如，如果我的数据在Maps.csv文件中如下所示：

County1     C:/maps/map1.pdf 
County1     C:/maps/map2.pdf 
County2     C:/maps/map1.pdf 
County2     C:/maps/map3.pdf 
County3     C:/maps/map3.pdf 
County4     C:/maps/map2.pdf 
County4     C:/maps/map4.pdf

如果二号线的县等于一号线的县，做点什么

下面的代码比较行，我想比较当前行和前一行之间的县值

import csv.

f = open("Maps.csv", "r+")
ff = csv.reader(f)

pre_line = ff.next()
while(True):
    try:
        cur_line = ff.next()
        if pre_line == cur_line:
            print "Matches"
        pre_line = cur_line
    except:
        break

我知道我可以获取当前值（见下文），但不知道如何获取以前的值。这可能吗？如果是的话，有人能告诉我怎么做吗。在第三天，我试图解决如何编写脚本，从csv文件中附加pdf文件的问题，我正要把咖啡杯扔到显示器上。我将这些数据分解成更小的部分，并使用更简单的数据作为试点。我的档案要大得多。有人建议我在论坛上发帖时一次只关注一个问题。这是我的最新一期。似乎无论我采取什么策略，我都无法以我想要的方式读取数据。啊

CurColor = row[color]

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使用python 2.7，您已经知道如何查找前一行。为什么不从该行获取所需的列

import csv.

f = open("Maps.csv", "r+")
ff = csv.reader(f)

pre_line = ff.next()
while(True):
    try:
        cur_line = ff.next()
        if pre_line[0] == cur_line[0]: # <-- compare first column
            print "Matches"
        pre_line = cur_line
    except:
        break

或者更简单地说：

pre_line = ff.next()
for cur_line in ff:
    if pre_line[0] == cur_line[0]: # <-- compare first column
        print "Matches"
    pre_line = cur_line

---

只需将csv文件读入行列表：rows=listf。现在，整个csv作为LST列表存储在内存中

import csv

f = open("Maps.csv", "r+")
# Use delimiters to split each line into different elements
# In my example i used a comma. Your csv may have a different delimiter
# make sure the delimiter is a single character string though
# so no multiple spaces between "County1     C:/maps/map1.pdf"
# it should be something like "County1,C:/maps/map1.pdf"
ff = csv.reader(f, delimiter=',')

COUNTY_INDEX = 0

# each time ff.next() is called, it makes an array variable ['County1', 'C:/maps/map1.pdf ']
# since you want to compare the value in the first index, then you need to reference it like so
# the line below will set pre_line = 'County1'
pre_line = ff.next()[COUNTY_INDEX]
while(True):
    try:
        # the current line will be 'County1' or 'County2' etc...Depending on which line is read
        cur_line = ff.next()[COUNTY_INDEX]
        if pre_line == cur_line:
            print "Matches"
        pre_line = cur_line
    except:
        break