Question

从下面的CSV文件获取行值时遇到一些问题

CSV
minzoom, maxzoom
0,5
5,10
10,18

我的代码：

i = 0
for line in open("C:/Marine/lookup/distinct_lookup_scales.csv"):
    i = i + 1
    if (i > 1):  #Skip header
        print("Line: " + line)
        #csv_row = line.split(',')
        minzoom = str(line[0])
        maxzoom = str(line[2])
        print("Minzoom:" + minzoom)
        print("Maxzoom:" + maxzoom)
        readShpFile(minzoom, maxzoom)

为 minzoom 和 maxzoom 返回的值已经

0   5
5   1
1   ,

我曾经使用过行拆分，但是恢复为尝试从行中获取项目不确定这是否是最好的方法

Answer 1

那不是您应该读取csv文件的方式。看看csv module documentation。

一个例子：

import csv

with open('C:/Marine/lookup/distinct_lookup_scales.csv', 'r') as csvfile:
    csvreader = csv.reader(csvfile)
    csvreader.next() #skip header
    for row in csvreader:
        minzoom = int(row[0])
        maxzoom = int(row[1])
        print('minzoom : {}'.format(minzoom))
        print('maxzoom : {}'.format(maxzoom))

您还可以使用DictReader，它将使用标题行生成字典。

import csv

with open('C:/Marine/lookup/distinct_lookup_scales.csv', 'r') as csvfile:
    csvreader = csv.DictReader(csvfile)
    for row in csvreader:
        minzoom = int(row['minzoom'])
        maxzoom = int(row['maxzoom'])
        print('minzoom : {}'.format(minzoom))
        print('maxzoom : {}'.format(maxzoom))

Answer 2

您可以尝试使用numpy.genfromtxt，例如：

import numpy as np

data = np.genfromtxt("C:/Marine/lookup/distinct_lookup_scales.csv", delimiter = ",",
                     skip_header = 1)
minzooms = data[:,0]
maxzooms = data[:,1]

使用Python读取CSV文件的值

2 个答案: