how does timedelta64[s] function works in python pandas

Question

below is link to my min dataset values

my timedeltah64[s] function is giving me wrong answers can someone explain to me where im going wrong with it

z =(data.iloc[1,8:9]-data.iloc[2,8:9]).astype('timedelta64[s]')
print(z)

result i'm getting

Time   -177.0
dtype: float64

instead of 3 seconds

Answer 1

Problems might be that you use iloc with 1 and 2. Since iloc is 0 indexed, you are actually subtracting the second row and the third row.

To get difference of consecutive rows, you can use diff() function

data['Time'].diff().astype('timedelta64[s]')