impose internal coherence (positive definite) on a matrix

#1
how do I turn a matrix which bears the resemblance of a variance covariance matrix into a "positive definite" matrix (=a usable var cov matrix) ?

is there any way?
 

spunky

Doesn't actually exist
#2
is there any particular reason as for why you're not using an actual positive definite matrix? or an actual covariance matrix that satisfies this and other properties?
 

hlsmith

Less is more. Stay pure. Stay poor.
#3
Because their name is shredder11 they can do what they want. Watch your mouth spunky and answer the question, NOW.