# MATLAB exponent problem

1. Jun 3, 2010

### swartzism

I am trying to do a very simple problem on MATLAB, but I do not know much about MATLAB so this is challenging. Here is the code:

Code (Text):

y=0:50:300;
D=0.210;          % D is the mean sediment diameter
w=14*D^(1.1);     % w is the particle fall speed
A=0.067*w^(0.44); % A is the sediment parameter
h=A*y^(2/3);      % h is the shoreline depth under water
plot (y,h);

What I would like to happen is produce a graph of h=1.005*y^(2/3) with coordinates of h from 0 to 5 in increments of 0.5 and coordinates of y from 0 to 300 in increments of 50. The error I get is:

??? Error using ==> mpower
Inputs must be a scalar and a square matrix.

Error in ==> beachprof at 5
h=A*y^(2/3); % h is the shoreline depth under water

What is going on here and how can I fix it?

2. Jun 3, 2010

### shoehorn

Your problem is in this line:

Code (Text):

h=A*y^(2/3);

What you want is:

Code (Text):

h=A*y.^(2/3);

To understand the difference, read the docs:

Code (Text):

doc mpower
doc power