Array indices must be positive integers or logical values.

clear 
close all
clc

t=[0:0.1:5];
M=2;
E=25;
B=(sin(M*pi.*t));
SC=E(1+exp(-t/4).*(sin(M*pi.*t)));

I'm trying to run this equations, but i'm getting an error that I don't understand.

Array indices must be positive integers or logical values.

Answer 1

[Geoff Hayes]

demoria - your E is a scalar (25) but you are treating it like an array at

SC=E(1+exp(-t/4).*(sin(M*pi.*t)));

and so the error message makes sense. Perhaps you need an operation (for example multiplication) here instead

SC = E * (1+exp(-t/4).*(sin(M*pi.*t)));