I have a dataframe that looks like below:
|userid|rank2017|rank2018|
|212 |'H' |'H' |
|322 |'L' |'H |
|311 |'H' |'L' |
I want to create a new column called progress in the the dataframe above that will output 1 if rank2017 is equal to rank2018, 2 if rank2017 is 'H' and rank2018 is 'L' else 3. can anybody help me execute this in python
Here is one way. You do not need to use nested if statements.
df = pd.DataFrame({'user': [212, 322, 311],
'rank2017': ['H', 'L', 'H'],
'rank2018': ['H', 'H', 'L']})
df['progress'] = 3
df.loc[(df['rank2017'] == 'L') & (df['rank2018'] == 'H'), 'progress'] = 2
df.loc[df['rank2017'] == df['rank2018'], 'progress'] = 1
# rank2017 rank2018 user progress
# 0 H H 212 1
# 1 L H 322 2
# 2 H L 311 3
Here is a way using np.select:
# Set your conditions:
conds = [(df['rank2017'] == df['rank2018']),
(df['rank2017'] == 'H') & (df['rank2018'] == 'L')]
# Set the values for each conditions
choices = [1, 2]
# Use np.select with a default of 3 (your "else" value)
df['progress'] = np.select(conds, choices, default = 3)
Returns:
>>> df
userid rank2017 rank2018 progress
0 212 H H 1
1 322 L H 3
2 311 H L 2
