[gradsusr] temporal correlation

[Ismaila Diallo]

Dear,
i have one data from model and observation and i want to correlate the temporal 
correlation between observation and model. For doing that i use a commend like:

define aa=pr.1
define bb=pr.2
define cc=tcorr(aa,bb,t=151,t=273)
d cc
therefore i get this error:
define r1=tcorr(aa,bb,t=151,t=273)
TCORR:  dim = 3, start = 151, end = 273
Data Request Error: Invalid grid coordinates
  World coordinates convert to non-integer  grid coordinates
    Variable = aa  Dimension = 3 
Error from TCORR:  Error getting grids
Operation Error:  Error from tcorr function
  Error ocurred at column 1
DEFINE error:  Invalid expression.


All comment are welcome.

Sincerely

ismaila