[SciPy-User] how does scipy.stats.t.isf work?

[neurino]

Honestly the full question is

"how does scipy.stats.t.isf work compared to common spreadsheets function
T.INV?"

I have to translate an excel calculation using TINV

In all excel, ooo or abiword I get:

TINV: inverse of the survival function of the Student t-distribution

Arguments:
p: probability
dof: number of degrees of freedom

The survival function is 1 minus the cumulative distribution function.

Note: If p < 0 or p > 1 or dof < 1 this function returns a #NUM! error.

Microsoft Excel: This function is Excel compatible.

Examples:
tinv(0,4;32) evaluates to 0,852998453651888.


while with scipy I get:

>>> from scipy.stats import t
>>> t.isf(.4, 32)
0.25546356665122449

Any advice welcome, please consider I'm an informatic but not a
mathematician.

Thanks for your support
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