Hp50 Real Matrix does not allow subst aij real by a'ij complex

[John Keith]

There are three types of arrays used by the HP 49 and 50-

Type 3: real array
Type 4: complex array
Type 29: symbolic array.

Real arrays must contain only real (floating-point) numbers.
Complex arrays must contain only complex (floating-point) numbers, e.g. (3., 4.).
Therefore, you cannot insert a complex number into a real array. Symbolic arrays may contain any type of number as well as algebraics, but matrix operations are generally slower with symbolic arrays.

If you are going to want to insert complex numbers into an array, you should start out with a complex array. You can turn a real array into a complex array with imaginary parts = 0 by
DUP SIZE 0 CON R\->C.