Attempt to reference field of non-structure array.

Hi, I'm trying to run the below code and its giving error as 'Attempt to reference field of non-structure array'.

code:

clc
close all
clear all
x=2;
D=[1 0 1 0];
X=[1;x;x.^2;x.^3];
dx=D.X;
gx=1+x+x.^3;

Could you please help to rectify this error?

Answer 1

[KSSV]

See this line

dx=D.X;

This should be element by element multiplication I guess. * is missing in that line. When you use simply '.', it is expecting D to be a structure, which is not.

clc
  close all
  clear all
  x=2;
  D=[1 0 1 0];
  X=[1;x;x.^2;x.^3];
  dx=D.*X;
  gx=1+x+x.^3;

Answer 2

[Andrei Bobrov]

Maybe this?

x=2;
D=[1 0 1 0];
X=[1;x;x.^2;x.^3];
dx=D*X;
gx=1+x+x.^3;