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SDEV - how is it calculated on the HP41CV?

PostPosted: Mon Aug 23, 2010 5:54 am
by andsen
Hi,

I am working on a open source HP41 simulator for the Android platform (http://android41cv.sourceforge.net/). I have implemented most of the functionality. I still miss to implement the SDEV function but I have not found out how the 41CV calculates the standard diviation based on Σx, Σ(x^2) and the number of x's.

I guess someone at forum.hp41.org knows the answer :-)

Regards Martin

Re: SDEV - how is it calculated on the HP41CV?

PostPosted: Thu Nov 18, 2010 9:08 pm
by andsen
After hours of serching for the correct formula I recieved a email with this formula which I have implemented in the a41cv.

sqrt ((sum(x^2) - sum(x)^2/n) / (n-1))

Martin