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Python Data Science Basics Cleaning Data Filtering Rows

Sahar Nasiri
Sahar Nasiri
7,454 Points


Why does she append the header to the filtered_rows list?

from s3v1 import *

def filter_col_by_string(data_sample, field, filter_condition):
    filtered_rows = []

    col = int(data_sample[0].index(field))

    for item in data_sample[1:]:
        if item[col] == filter_condition:

    return filtered_rows

silk_ties = filter_col_by_string(data_from_csv, "material", "_silk")
print("Found {} silk ties".format(number_of_records(silk_ties)))

wool_ties = filter_col_by_string(data_from_csv, "material", "_wool")
print("Found {} wool ties".format(number_of_records(wool_ties)))

cotton_ties = filter_col_by_string(data_from_csv, "material", "_cotton")
print("Found {} cotton ties".format(number_of_records(cotton_ties)))

gucci_ties = filter_col_by_string(data_from_csv, "brandName", "_Gucci")
print("Found {} Gucci ties".format(number_of_records(gucci_ties)))

1 Answer

Stephen Cole
Stephen Cole
Courses Plus Student 12,909 Points

So far, it appears that she uses logic to search for data by the column name, not the number. By adding a heading, if she searches in the future, she won't need to know the column number, just its heading.

col = int(data_sample[0].index(field))