How to iterate through rows of a DataFrame and add those rows to a blank DataFrame?

Question

I have two populated DataFrames, df1 and df2. I also have an empty Dataframe (test):

df1 = pd.read_excel(xlpath1, sheetname='Sheet1')
df2 = pd.read_excel(xlpath2, sheetname='Sheet1')
test = pd.DataFrame()

I'd like to iterate through the rows of df1 and add those rows to the empty test Dataframe. When I try the following, I don't get any sort of error, but nothing is added to the test DataFrame:

for i, j in df1.iterrows():
    test.append(j)

Any ideas? Do I need to add the proper columns to the test DataFrame first? My total end-goal is to iterate through multiple DataFrames and add only unique items to the empty DataFrame (ex, adding items that appear in one of the many DataFrames).

You should avoid both iterating over the rows and [appending to a DataFrame within a loop](https://stackoverflow.com/a/37009561/4333359). Can you provide some sample DataFrames and you expected output? Likely just concatenate them and then drop duplicates. — ALollz, Jun 11 '19 at 15:59

Shubham Rajput · Accepted Answer · 2019-06-11T16:51:58.460

1

If are trying to append dataframe df1 on empty dataframe df2 you can use concat function of pandas.

test = pd.concat([df1, test], axis = 0)

axis = 0 ; for appending two dataframes row-wise

edited Jun 11 '19 at 16:51

answered Jun 11 '19 at 16:07

Shubham Rajput

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What is the 'anomalies' item? – Jared Jun 11 '19 at 16:16

How to iterate through rows of a DataFrame and add those rows to a blank DataFrame?

1 Answers1