LENGTH determines the length of a list. It is useful in PROCs which are passed lists as arguments, since the length may be required in matrix dimensions or degrees of freedom calculations. This command counts arguments; it does not compute the length of a series or a matrix.
LENGTH <list of variables or lists> <length of list> ;
Output
The list(s) on the command line are expanded, and the final total number of items is stored in the last argument.
Count the number of parameters from an estimation:
LSQ EQ1-EQ5;
LENGTH @RNMS NOPAR;
The following commands cause LENA to be stored with a value of 3, and LENAB to be stored with a value of 5:
LIST LA X Y Z;
LENGTH LA LENA;
LIST BB B1-B2;
LENGTH LA BB LENAB;