ERROR: (execution) Matrices do not conform to the operation

[Cnord]

I am having a problem in this coding. I cannot figure out what is the problem with the operands "[". Can anyone helping me out ?

[Rick_SAS]

The error is on the statement

u1[i] = u1;

The left hand side is a scalar. The right hand side is a vector.

[Cnord]

however when i remove the statement :
u1[i]=u1
another error occurs.
Error: matrix is not defined
the error occur at the statement
u1=u[p+1:t,]
where the error occurs at the operand '[' also

[Rick_SAS]

If you would like help, please

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