pandas dataframe sum with groupby

Question

I have a pandas dataframe that structurally looks like this:

[
    [\'x\', \'1\', \'-7\']
    [\'x\', \'2\', \'-2\']
    [\'y\', \'3\', \'-1\']
    [\'y\', \'4\'         


        

Answer 1

setup
I converted your string numbers to actual numbers

df = pd.DataFrame(
    [
        ['x', '1', '-7'],
        ['x', '2', '-2'],
        ['y', '3', '-1'],
        ['y', '4', '-3']
    ]
)

df[1] = pd.to_numeric(df[1])
df[2] = pd.to_numeric(df[2])

solution

df.groupby(0).sum()