If/else in pandas ValueError

Question

I have the following code:

if data['Open'] >= data['Close']:
    data['Color'] = 'True'

What i want to do is compare the two addGreen or Red in [Color] column in pandas. But i am getting

ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().

How can i fix this?

simply do `data['Color'] = data['Open'] >= data['Close']` – anky Jan 26 '20 at 05:12 — anky, Jan 26 '20 at 05:12

Allen Qin · Accepted Answer · 2020-01-26T05:19:18.303

2

Try this to see if it works:

import numpy as np
data['Color'] = np.where(data['Open'] >= data['Close'], 'True', 'whatever_value_you_want_if_the_condition_is_false')

edited Jan 26 '20 at 05:19

answered Jan 26 '20 at 05:08

Allen Qin

There is no column 'color' yet i think that is why i am getting `KeyError: 'Color'` – Slartibartfast Jan 26 '20 at 05:15
If the condition is not true, what value you want to assign to data['Color']? – Allen Qin Jan 26 '20 at 05:18

1 Answers1