st: Erreor message after Mata: sizeof()

[Thomas Corneli�en <cornelissen@ewifo.uni-hannover.de>]

Dear all,
I get an error message after using sizeof(X) in Mata. Example see below. 
What have I done wrong?
If I understand the manual right, I typed exactly what I am supposed to 
type.
Thomas

. mata
------------------------------------------------- mata (type end to 
exit) --------------------------------
: X=J(100,100,3)

: mata describe

     # bytes   type                        name and extent
-------------------------------------------------------------------------------
      80,000   real matrix                 X[100,100]
-------------------------------------------------------------------------------

: sizeof(X)
'sizeof' found where almost anything else expected
r(3000);

:

-------------------------------------------------------------------------
Thomas Cornelissen
Institute of Empirical Economic Research
Leibniz Universit�t Hannover, Germany
cornelissen@ewifo.uni-hannover.de 
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