Reading .csv file with Python and DictReader missing columns

Question

I have the following .csv file I'm trying to read as a whole:

---------------------------------------------------------------
#INFO            |           |        |       |        |      |
---------------------------------------------------------------
#Study name      | g1        |        |       |        |      |
---------------------------------------------------------------
#Respondent Name | name      |        |       |        |      |
---------------------------------------------------------------
#Respondent Age  | 20        |        |       |        |      |
---------------------------------------------------------------
#DATA            |           |        |       |        |      |
---------------------------------------------------------------
Row              | Timestamp | Source | Event | Sample | Anger|
---------------------------------------------------------------
1                | 133       | Face   | 1     | 3      | 0.44 |
---------------------------------------------------------------
2                | 240       | Face   | 1     | 4      | 0.20 |
---------------------------------------------------------------
3                | 12        | Face   | 1     | 5      | 0.13 |
---------------------------------------------------------------
4                | 133       | Face   | 1     | 6      | 0.75 |
---------------------------------------------------------------
5                | 87        | Face   | 1     | 7      | 0.25 |
---------------------------------------------------------------

Image of the file

This is the code I am using to open, read the file, and print to the terminal:

import csv

def read_csv():
    with open("in/2.csv", encoding="utf-8-sig") as f:
        reader = csv.DictReader(f)
        print(list(reader))
read_csv()

The output I am getting includes only the first two columns of my .csv:

[{'#INFO': '#Study name', '': ''}, {'#INFO': '#Respondent Name', '': ''}, {'#INFO': '#Respondent Age', '': ''}, {'#INFO': '#DATA', '': ''}, {'#INFO': 'Row', '': 'Anger'}, {'#INFO': '1', '': '4.40E-01'}, {'#INFO': '2', '': '2.00E-01'}, {'#INFO': '3', '': '1.30E-01'}, {'#INFO': '4', '': '7.50E-01'}, {'#INFO': '5', '': '2.50E-01'}]

Why are the other columns missing from my output? I want the other columns starting from Row to be included as well. Any direction would be appreciated. Thanks!

The reader expects a file where the first row contains column names and following rows contain data entries. — Michael Butscher
– Michael Butscher, Commented Dec 28, 2022 at 10:40
@MichaelButscher, I see. Thanks for letting me know. What would be a good approach to ignore the first n rows? Also, feel free to add your comment as an answer, and I'll gladly mark it as resolved. — ChenBr
– ChenBr, Commented Dec 28, 2022 at 10:43
There are many questions and answers on this topic: stackoverflow.com/questions/48716446/… , stackoverflow.com/questions/11349333/… — XaC
– XaC, Commented Dec 28, 2022 at 10:55

Michael Butscher · Accepted Answer · 2022-12-28 10:53:49Z

2

The DictReader expects a file where the first row contains column names (each name different from each other) and following rows contain data entries. If multiple column names are just empty strings, the value in the last column is assigned to key '' in the returned dictionary.

To skip the first five lines instead, you can write:

import csv

def read_csv():
    with open("in/2.csv", encoding="utf-8-sig") as f:
        for _ in range(5):
            next(f)

        reader = csv.DictReader(f)
        print(list(reader))
read_csv()

answered Dec 28, 2022 at 10:53

Michael Butscher

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Yevhen Kuzmovych · Accepted Answer · 2022-12-28 10:53:33Z

2

Try:

for _ in zip(f, range(5)): 
    pass

before initializing DictReader. This should skip the first 5 lines.

import csv

def read_csv():
    with open("in/2.csv", encoding="utf-8-sig") as f:
        for _ in zip(f, range(5)): 
            pass
        reader = csv.DictReader(f)
        print(list(reader))
read_csv()

answered Dec 28, 2022 at 10:53

Yevhen Kuzmovych

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