How to import a csv file using python with headers intact, where first column is a non-numerical

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This is an elaboration of a previous question, but as I delve deeper into python, I just get more confused as to how python handles csv files.

I have a csv file, and it must stay that way (e.g., cannot convert it to text file). It is the equivalent of a 5 rows by 11 columns array or matrix, or vector.

I have been attempting to read in the csv using various methods I have found here and other places (e.g. python.org) so that it preserves the relationship between columns and rows, where the first row and the first column = non-numerical values. The rest are float values, and contain a mixture of positive and negative floats.

What I wish to do is import the csv and compile it in python so that if I were to reference a column header, it would return its associated values stored in the rows. For example:

>>> workers, constant, age
>>> workers
    w0
    w1
    w2
    w3
    constant
    7.334
    5.235
    3.225
    0
    age
    -1.406
    -4.936
    -1.478
    0

And so forth...

I am looking for techniques for handling this kind of data structure. I am very new to python.

csv python
4 Answers

You can use pandas library and reference the rows and columns like this:

import pandas as pd

input = pd.read_csv("path_to_file");

#for accessing ith row:
input.iloc[i]

#for accessing column named X
input.X

#for accessing ith row and column named X
input.iloc[i].X
user_20474220

I recently had to write this method for quite a large datafile, and i found using list comprehension worked quite well

      import csv
      with open("file.csv",'r') as f:
        reader = csv.reader(f)
        headers = next(reader)
        data = [{h:x for (h,x) in zip(headers,row)} for row in reader]
        #data now contains a list of the rows, with each row containing a dictionary 
        #  in the shape {header: value}. If a row terminates early (e.g. there are 12 columns, 
        #  it only has 11 values) the dictionary will not contain a header value for that row.
user_8512720
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