blocks|key|527896|text|要跳过第一行，只需调用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|527897|next(inf)|code-block|syntax|javascript|527898|Python中的文件是行上的迭代器。|527899|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

To skip the first line just call:

<pre><code>next(inf)
</code></pre>

Files in Python are iterators over lines.

blocks|key|311148|text|从python+cookbook借来的|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|311149|更简洁的模板代码可能如下所示：|311150|import+csv
with+open('stocks.csv')+as+f:
++++f_csv+=+csv.reader(f)+
++++headers+=+next(f_csv)+
++++for+row+in+f_csv:
++++++++#+Process+row+...|code-block|syntax|javascript|311151|entityMap|0|LINK|mutability|MUTABLE|url|https://rads.stackoverflow.com/amzn/click/com/B00DQV4GGY^0|1|F|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|6|7|W|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|X|8|@]|9|@]|C|$I|J]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

Borrowed from <a href="https://rads.stackoverflow.com/amzn/click/com/B00DQV4GGY" rel="noreferrer" rel="nofollow noreferrer">python cookbook</a>, 
A more concise template code might look like this: 

<pre><code>import csv
with open('stocks.csv') as f:
 f_csv = csv.reader(f) 
 headers = next(f_csv) 
 for row in f_csv:
 # Process row ...
</code></pre>

blocks|key|311061|text|在类似的用例中，我必须在带有实际列名的行之前跳过恼人的行。这个解决方案运行得很好。首先读取文件，然后将列表传递给csv.DictReader。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|311062|with+open('all16.csv')+as+tmp:
++++#+Skip+first+line+(if+any)
++++next(tmp,+None)

++++#+{line_num:+row}
++++data+=+dict(enumerate(csv.DictReader(tmp)))|code-block|syntax|javascript|311063|entityMap^0|1K|E|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

In a similar use case I had to skip annoying lines before the line with my actual column names. This solution worked nicely. Read the file first, then pass the list to <code>csv.DictReader</code>.

<pre><code>with open('all16.csv') as tmp:
 # Skip first line (if any)
 next(tmp, None)

 # {line_num: row}
 data = dict(enumerate(csv.DictReader(tmp)))
</code></pre>

blocks|key|310896|text|您通常会使用next(incsv)，它使迭代器前进一行，因此您可以跳过标题。另一个(假设您想跳过30行)是：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|310897|from+itertools+import+islice
for+row+in+islice(incsv,+30,+None):
++++#+process|code-block|syntax|javascript|310898|entityMap^0|6|B|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

You would normally use <code>next(incsv)</code> which advances the iterator one row, so you skip the header. The other (say you wanted to skip 30 rows) would be:

<pre><code>from itertools import islice
for row in islice(incsv, 30, None):
 # process
</code></pre>

blocks|key|310939|text|使用csv.DictReader而不是csv.Reader。如果省略fieldnames参数，则csvfile第一行中的值将用作字段名。然后，您将能够使用行“1”等访问字段值|type|unstyled|depth|inlineStyleRanges|entityRanges|data|310940|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

use csv.DictReader instead of csv.Reader.
If the fieldnames parameter is omitted, the values in the first row of the csvfile will be used as field names. you would then be able to access field values using row["1"] etc

blocks|key|311245|text|documentation+for+the+Python+3+CSV+module提供了以下示例：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|311246|with+open('example.csv',+newline='')+as+csvfile:
++++dialect+=+csv.Sniffer().sniff(csvfile.read(1024))
++++csvfile.seek(0)
++++reader+=+csv.reader(csvfile,+dialect)
++++#+...+process+CSV+file+contents+here+...|code-block|syntax|javascript|311247|Sniffer将尝试自动检测有关CSV文件的许多内容。您需要显式调用它的has_header()方法来确定文件是否有标题行。如果是，则在迭代CSV行时跳过第一行。你可以这样做：|style|CODE|311248|if+sniffer.has_header():
++++for+header_row+in+reader:
++++++++break
for+data_row+in+reader:
++++#+do+something+with+the+row|311249|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.python.org/3/library/csv.html#csv.Sniffer^0|0|15|0|0|0|0|7|10|C|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|11|8|@$A|12|B|13|K|L]|$A|14|B|15|K|L]]|9|@]|C|$]]|$1|M|3|N|5|F|7|16|8|@]|9|@]|C|$G|H]]|$1|O|3|-4|5|6|7|17|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

The <a href="https://docs.python.org/3/library/csv.html#csv.Sniffer" rel="nofollow noreferrer">documentation for the Python 3 CSV module</a> provides this example:

<pre><code>with open('example.csv', newline='') as csvfile:
 dialect = csv.Sniffer().sniff(csvfile.read(1024))
 csvfile.seek(0)
 reader = csv.reader(csvfile, dialect)
 # ... process CSV file contents here ...
</code></pre>

The <code>Sniffer</code> will try to auto-detect many things about the CSV file. You need to explicitly call its <code>has_header()</code> method to determine whether the file has a header line. If it does, then skip the first row when iterating the CSV rows. You can do it like this:

<pre><code>if sniffer.has_header():
 for header_row in reader:
 break
for data_row in reader:
 # do something with the row
</code></pre>

blocks|key|310985|text|新的'pandas‘包可能比'csv’更相关。下面的代码将读取CSV文件，默认情况下将第一行解释为列标题，并查找列之间的最小值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|310986|import+pandas+as+pd

data+=+pd.read_csv('all16.csv')
data.min()|code-block|syntax|javascript|310987|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

The new 'pandas' package might be more relevant than 'csv'. The code below will read a CSV file, by default interpreting the first line as the column header and find the minimum across columns.

<pre><code>import pandas as pd

data = pd.read_csv('all16.csv')
data.min()
</code></pre>

blocks|key|528119|text|因为这与我正在做的事情有关，所以我将在这里分享。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|528120|如果我们不确定是否有头文件，并且您也不想导入sniffer和其他东西，该怎么办？|528121|如果您的任务是基本任务，例如打印或附加到列表或数组，则只需使用If语句：|528122|#+Let's+say+there's+4+columns
with+open('file.csv')+as+csvfile:
+++++csvreader+=+csv.reader(csvfile)
#+read+first+line
+++++first_line+=+next(csvreader)
#+My+headers+were+just+text.+You+can+use+any+suitable+conditional+here
+++++if+len(first_line)+==+4:
++++++++++array.append(first_line)
#+Now+we'll+just+iterate+over+everything+else+as+usual:
+++++for+row+in+csvreader:
++++++++++array.append(row)|code-block|syntax|javascript|528123|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|O|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|P|8|@]|9|@]|A|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Because this is related to something I was doing, I'll share here. 

What if we're not sure if there's a header and you also don't feel like importing sniffer and other things? 

If your task is basic, such as printing or appending to a list or array, you could just use an if statement:

<pre><code># Let's say there's 4 columns
with open('file.csv') as csvfile:
 csvreader = csv.reader(csvfile)
# read first line
 first_line = next(csvreader)
# My headers were just text. You can use any suitable conditional here
 if len(first_line) == 4:
 array.append(first_line)
# Now we'll just iterate over everything else as usual:
 for row in csvreader:
 array.append(row)
</code></pre>

blocks|key|311018|text|嗯，我的mini+wrapper+library也可以完成这项工作。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|311019|>>>+import+pyexcel+as+pe
>>>+data+=+pe.load('all16.csv',+name_columns_by_row=0)
>>>+min(data.column[1])|code-block|syntax|javascript|311020|同时，如果你知道头列索引是什么，比如"Column+1"，你可以这样做：|311021|>>>+min(data.column["Column+1"])|311022|entityMap|0|LINK|mutability|MUTABLE|url|http://pyexcel.readthedocs.org/en/v0.0.9/index.html^0|4|K|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]]]

Well, my <a href="http://pyexcel.readthedocs.org/en/v0.0.9/index.html" rel="nofollow">mini wrapper library</a> would do the job as well.

<pre><code>&gt;&gt;&gt; import pyexcel as pe
&gt;&gt;&gt; data = pe.load('all16.csv', name_columns_by_row=0)
&gt;&gt;&gt; min(data.column[1])
</code></pre>

Meanwhile, if you know what header column index one is, for example "Column 1", you can do this instead:

<pre><code>&gt;&gt;&gt; min(data.column["Column 1"])
</code></pre>

blocks|key|528053|text|对我来说，最简单的方法是使用range。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|528054|import+csv

with+open('files/filename.csv')+as+I:
++++reader+=+csv.reader(I)
++++fulllist+=+list(reader)

#+Starting+with+data+skipping+header
for+item+in+range(1,+len(fulllist)):+
++++#+Print+each+row+using+"item"+as+the+index+value
++++print+(fulllist[item])++|code-block|syntax|javascript|528055|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

For me the easiest way to go is to use range. 

<pre><code>import csv

with open('files/filename.csv') as I:
 reader = csv.reader(I)
 fulllist = list(reader)

# Starting with data skipping header
for item in range(1, len(fulllist)): 
 # Print each row using "item" as the index value
 print (fulllist[item]) 
</code></pre>

blocks|key|528208|text|我会将csvreader转换为list，然后弹出第一个元素|type|unstyled|depth|inlineStyleRanges|entityRanges|data|528209|import+csv++++++++

with+open(fileName,+'r')+as+csvfile:
++++++++csvreader+=+csv.reader(csvfile)
++++++++data+=+list(csvreader)+++++++++++++++#+Convert+to+list
++++++++data.pop(0)++++++++++++++++++++++++++#+Removes+the+first+row

++++++++for+row+in+data:
++++++++++++print(row)|code-block|syntax|javascript|528210|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I would convert csvreader to list, then pop the first element

<pre><code>import csv 

with open(fileName, 'r') as csvfile:
 csvreader = csv.reader(csvfile)
 data = list(csvreader) # Convert to list
 data.pop(0) # Removes the first row

 for row in data:
 print(row)
</code></pre>

blocks|key|311369|text|这可能是一个非常古老的问题，但是对于熊猫，我们有一个非常简单的解决方案|type|unstyled|depth|inlineStyleRanges|entityRanges|data|311370|import+pandas+as+pd

data=pd.read_csv('all16.csv',skiprows=1)
data['column'].min()|code-block|syntax|javascript|311371|使用skiprows=1，我们可以跳过第一行，然后使用data‘’column‘.min()找到最小值。|311372|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

this might be a very old question but with pandas we have a very easy solution
<pre><code>import pandas as pd

data=pd.read_csv('all16.csv',skiprows=1)
data['column'].min()
</code></pre>
with skiprows=1 we can skip the first row then we can find the least value using data['column'].min()

blocks|key|311102|text|Python+3.X|type|unstyled|depth|inlineStyleRanges|entityRanges|data|311103|处理UTF8物料清单%2B标题|311104|非常令人沮丧的是，csv模块不能很容易地获得头文件，UTF-8BOM(文件中的第一个字符)也有一个bug。这只适用于我使用csv模块：|offset|length|style|CODE|311105|import+csv

def+read_csv(self,+csv_path,+delimiter):
++++with+open(csv_path,+newline='',+encoding='utf-8')+as+f:
++++++++#+https://bugs.python.org/issue7185
++++++++#+Remove+UTF8+BOM.
++++++++txt+=+f.read()[1:]

++++#+Remove+header+line.
++++header+=+txt.splitlines()[:1]
++++lines+=+txt.splitlines()[1:]

++++#+Convert+to+list.
++++csv_rows+=+list(csv.reader(lines,+delimiter=delimiter))

++++for+row+in+csv_rows:
++++++++value+=+row[INDEX_HERE]|code-block|syntax|javascript|311106|entityMap^0|0|0|9|3|1P|3|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|S|8|@$F|T|G|U|H|I]|$F|V|G|W|H|I]]|9|@]|A|$]]|$1|J|3|K|5|L|7|X|8|@]|9|@]|A|$M|N]]|$1|O|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|P|$]]

Python 3.X

Handles UTF8 BOM + HEADER

It was quite frustrating that the <code>csv</code> module could not easily get the header, there is also a bug with the UTF-8 BOM (first char in file).
This works for me using only the <code>csv</code> module:

<pre><code>import csv

def read_csv(self, csv_path, delimiter):
 with open(csv_path, newline='', encoding='utf-8') as f:
 # https://bugs.python.org/issue7185
 # Remove UTF8 BOM.
 txt = f.read()[1:]

 # Remove header line.
 header = txt.splitlines()[:1]
 lines = txt.splitlines()[1:]

 # Convert to list.
 csv_rows = list(csv.reader(lines, delimiter=delimiter))

 for row in csv_rows:
 value = row[INDEX_HERE]
</code></pre>

blocks|key|528353|text|简单的解决方案是使用csv.DictReader()|type|unstyled|depth|inlineStyleRanges|entityRanges|data|528354|import+csv

def+read_csv(file):+with+open(file,+'r')+as+file:
++++reader+=+csv.DictReader(file)
++++for+row+in+reader:
++++++++print(row["column_name"])++#+Replace+the+name+of+column+header.|code-block|syntax|javascript|528355|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Simple Solution is to use csv.DictReader()
<pre><code>import csv

def read_csv(file): with open(file, 'r') as file:
 reader = csv.DictReader(file)
 for row in reader:
 print(row[&quot;column_name&quot;]) # Replace the name of column header.
</code></pre>

I am asking Python to print the minimum number from a column of CSV data, but the top row is the column number, and I don't want Python to take the top row into account. How can I make sure Python ignores the first line?

This is the code so far:

<pre><code>import csv

with open('all16.csv', 'rb') as inf:
 incsv = csv.reader(inf)
 column = 1 
 datatype = float 
 data = (datatype(column) for row in incsv) 
 least_value = min(data)

print least_value
</code></pre>

Could you also explain what you are doing, not just give the code? I am very very new to Python and would like to make sure I understand everything.

How to ignore the first line of data when processing CSV data?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我要求Python打印CSV数据列中的最小数字，但顶行是列号，我不希望Python将顶行考虑在内。如何确保Python忽略第一行？这是目前为止的代码：import csvwith open('all16.csv', 'rb') as inf:    incsv = csv.reader(inf)    column = 1                    datatype = float  

问如何在处理CSV数据时忽略第一行数据？
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问如何在处理CSV数据时忽略第一行数据？EN

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问如何在处理CSV数据时忽略第一行数据？
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