# How can I get two-tailed inverse of the student's t-distribution?

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Josef Hrdlicka on 16 Mar 2021
Commented: Josef Hrdlicka on 17 Mar 2021
So I'd like to use a function that I found in excel - T.INV.2T(1 - (% / 100) , n - 1 ), where n - 1 is the degrees of freedom.
For example: accuracy of measuring = 99.73%, measuring n = 10. With excel function I've got the t = 4.09. How do I get this t number in matlab?
It's for the purpouse of equation:
I tried all different combinations of functions: tinv(), tcdf()...nothing worked. I'm an applied science student and I'm completley new to statistics. I've spent many hours on finding out how to calculate the 'right' student t-distribution. Found one in excel, but can't find the right one in matlab. By the way this is for homework in my physics lab. Hope you can help me.

Jeff Miller on 16 Mar 2021
Not sure if this is really what you want, but in MATLAB:
a=tinv(1-(1-.9973)/2,10-1)
a =
4.0942
Josef Hrdlicka on 17 Mar 2021
Exactley what I needed! I've actually tried this division by 2 before, but I divided the whole thing (1-(1-.9973))/2 instead of just the one part of it.
Thank you sir.

R2021a

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