在Python中从CSV删除列

Question

I know similar questions to this have been asked, but I couldn't find any that were dealing with the error I'm getting (though I apologize if I'm missing something!). I am trying to remove a few columns from a CSV that wouldn't load in Excel so I couldn't just delete them within the file. I have the following code:

import os
import pandas as pd
os.chdir(r"C:\Users\maria\Desktop\Project\North American Breeding Bird Survey")
data = pd.read_csv("NABBSStateData.csv")
data.drop(["CountryNum", "Route", "RPID"], axis = 1, inplace = True)

but when I run it I get this error message:

c:\program files (x86)\microsoft visual studio\2019\professional\common7\ide\extensions\microsoft\python\core\Packages\ptvsd\_vendored\pydevd\pydevd.py:1664: DtypeWarning: Columns (0,1,2,3,4,5,6,7,8,9,10,11,12,13) have mixed types. Specify dtype option on import or set low_memory=False.
  return self._exec(is_module, entry_point_fn, module_name, file, globals, locals)

I am relatively new to python/visual studio, and I am having a hard time figuring out what this error message is saying and how to fix it. Thank you!!

Edit: The CSV in question is the state files from this site concatenated together, so you can open one of the state files to see the columns/data types.

Answer 1

Looks like you have mixed data types in some of your columns (eg columns 0,1,2,3,4,5,6,7,8,9,10,11,12,13). Mixed data type means in one column, say column 'a', most rows are numbers, but there might be strings in some rows as well.

Try use dtype option from pd.read_csv to specify the column types. If you are not sure about the type, use object or str . This is an example:

df = pd.read_csv('D:\\foo.csv', header=0, dtype={'currency':str, 'v1':object, 'v2':object})

A link to use read_csv

Here's list of all the types you can specify .