Cindy,
I dont know of a better way to do this than what Ted Harding showed. Dan Daniel J. Nordlund Washington State Department of Social and Health Services Planning, Performance, and Accountability Research and Data Analysis Division Olympia, WA 98504-5204 From: cindy Guo [mailto:[email protected]] Sent: Monday, August 10, 2009 7:05 PM To: Nordlund, Dan (DSHS/RDA) Cc: [email protected] Subject: Re: [R] matrix power Hi, Dan, Yes, this is what I want. Is there better way to solve this? Cindy On Mon, Aug 10, 2009 at 2:52 PM, Nordlund, Dan (DSHS/RDA) <[email protected]> wrote: > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of cindy Guo > Sent: Monday, August 10, 2009 2:32 PM > To: [email protected] > Subject: [R] matrix power > > Hi, All, > > If I have a symmetric matrix, how can I get the negative square root of the > matrx, ie. X^(-1/2) ? > > Thanks, > > Cindy > Cindy, Just to be sure we are all on the same page. Are saying you have a matrix X, and you want to find the a matrix A such that X = A %*% A And you want to then find the matrix inverse of A ? Dan Daniel J. Nordlund Washington State Department of Social and Health Services Planning, Performance, and Accountability Research and Data Analysis Division Olympia, WA 98504-5204 [[alternative HTML version deleted]]
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