Extract csv file specific columns to list in Python

Question

What I m trying to do is plot the latitude and longitude values of specific storms on a map using matplotlib basemap python  etc  My problem is that I m trying to extract the latitude  longitude  and name of the storms on map but I keep getting errors between lines 41-44 where I try to extract the columns into the list  Could someone please help me figure this out  Thanks in advance   Here is what the file looks like   1957 AUDREY HU  21 6N  93 3W 1957 AUDREY HU 22 0N   93 4W 1957 AUDREY HU 22 6N   93 5W 1957 AUDREY HU 23 2N   93 6W   I want the list to look like the following   latitude    21 6N 22 0N 23 4N  longitude    93 3W  93 5W 93 8W  name     Audrey   Audrey     Here s what I have so far   data   np loadtxt  louisianastormb csv  dtype np str delimiter     skiprows 1     print data     data   np loadtxt  louisianastormb csv  dtype np str delimiter     skiprows 0   f  open  louisianastormb csv    rb   reader   csv reader f  delimiter      header   reader next   zipped   zip  reader   latitude   zipped 3  longitude   zipped 4  names   zipped 1  x  y   m longitude  latitude    Here s the last error message traceback I received      Traceback  most recent call last     File   home darealmzd lstorms py   line 42  in                      header   reader next      csv Error  new-line character seen in unquoted field - do you need to open the file in universal-newline mode

User · Accepted Answer

This looks like a problem with line endings in your code. If you're going to be using all these other scientific packages, you may as well use Pandas for the CSV reading part, which is both more robust and more useful than just the csv module:

import pandas
colnames = ['year', 'name', 'city', 'latitude', 'longitude']
data = pandas.read_csv('test.csv', names=colnames)

If you want your lists as in the question, you can now do:

names = data.name.tolist()
latitude = data.latitude.tolist()
longitude = data.longitude.tolist()

User · Answer

import csv from sys import argv  d   open  mydata csv    r    db       for line in csv reader d       db append line     the rest of your code with  db  filled with your list of lists as rows and columbs of your csv file

User · Answer

A standard-lib version  no pandas   This assumes that the first row of the csv is the headers  import csv    open the file in universal line ending mode  with open  test csv    rU   as infile      read the file as a dictionary for each row   header   value     reader   csv DictReader infile    data        for row in reader      for header  value in row items          try          data header  append value        except KeyError          data header     value     extract the variables you want names   data  name   latitude   data  latitude   longitude   data  longitude

[python] Extract csv file specific columns to list in Python

Examples related to python

Examples related to csv

Examples related to numpy

Examples related to matplotlib