 Usage:  covvals = SPKRexpcov (r, d, alpha, se)  

 

 Input:



  r                      n x 1 - vector of distances at which to evaluate the 

                         covariance 

                         

  d                      scalar - range parameter 

                         

  alpha                  sclar - proportion of nugget effect 

                         

  se                     scalar - standard deviation at distance zero 

                         

 Output:



  res                    n x 1 - vector of covariance values 

                         

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(C) MD*TECH Method and Data Technologies, 21.9.2000

