MATLAB: About error in stateflow

Question

dear,

when i implement stateflow in block to mult or add signals in stateflow, i have this error:

_Cannot solve algebraic loop involving 'SUMOFPRODUCT/Sumofproduct/Product1' because it consists of blocks that cannot be assigned algebraic variables, i.e., blocks with discrete-valued outputs, blocks with non-double or complex outputs, Stateflow blocks, or nonvirtual subsystems

Need for helping!

Best regards!

Pham van Dung

Answer 1

You have an algebraic loop means that in your model you have a feedback through a block which don't contain any delay, it's like you write y(n)=2*y(n)+1, which is not correct, you should write y(n+1)=2*y(n)+1. to correct insert before your feedback a unit delay block