I want to get the numpy.std
of each column of my pandas.DataFrame
.
Here is my code:
import pandas as pd
import numpy as np
prices = pd.DataFrame([[-0.33333333, -0.25343423, -0.1666666667],
[+0.23432323, +0.14285714, -0.0769230769],
[+0.42857143, +0.07692308, +0.1818181818]])
print(pd.DataFrame(prices.std(axis=0)))
Here is my code's output:
pd.DataFrame([[ 0.39590933],
[ 0.21234018],
[ 0.1809432 ]])
And here is the right output (if calculate with np.std
)
pd.DataFrame([[ 0.32325862],
[ 0.17337503],
[ 0.1477395 ]])
Why am I having such difference?
How can I fix that?
NOTE: I have tried to do this way:
print(np.std(prices, axis=0))
But I had the following error:
Traceback (most recent call last):
File "C:Users*****Documents****************.py", line 10, in <module>
print(np.std(prices, axis=0))
File "C:Python33libsite-packages
umpycorefromnumeric.py", line 2812, in std
return std(axis=axis, dtype=dtype, out=out, ddof=ddof)
TypeError: std() got an unexpected keyword argument 'dtype'
Thank you!
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