擅长:python、mysql、java
<p>既然您已经了解了Python的<a href="http://docs.python.org/2/library/csv.html" rel="nofollow">csv library</a>,那么对于输入csv的每一行,创建一个包含所需更改的新行,并将其写入一个新的csv文件,这应该很简单。在</p>
<p>请注意csv阅读器如何将每一行视为一个列表。接下来,查看csv writer的<a href="http://docs.python.org/2/library/csv.html#csv.csvwriter.writerow" rel="nofollow">^{<cd1>}</a>方法;它接受一个python列表并将其作为csv行写入。你需要做的就是一次读一行,做你想要的修改,然后把它吐出来给作者。使用您的代码:</p>
<pre><code>for row in reader: #for each row in the input
outrow = list(row) # make a copy of the row. I'm not sure if you NEED to do this, but it doesn't hurt.
if outrow[2] == "yes": #if the value in the 3rd column, "smoker", is "yes"
outrow[2] = 1 #change it to 1
elif outrow[2] == "no": #if it's "no"
outrow[2] = 0 #change it to 0.
#repeat this process for outrow[3] (meaning column #4, "do sport")
output.writerow(outrow)
</code></pre>
<p>您可能注意到python调用第3列2和第4列3这是因为python从0开始计数(所以第一列是第0列)。您应该能够按照这个例子来进行所有需要的更改。在</p>
<p>完成后别忘了关闭文件!在</p>