Need help with plotting a graph on matlab- linewidth

I was wondering if someone could tell me why I get this error returning:

Error using plot
String argument is an unknown option.

Whenever I try to add the 'linewidth',2 parameter for the plot function.

Here's my code:

h1 = sin(x)+x^2/7-0.3;
g1 = cosh(0.2*x);
x_values = 0:.04:4;
y_values=subs(h1,x_values);

figure(2);clf reset
plot(x_values,y_values,'b:',x_values,subs(g1,x_values),'r');
title('Plot of two functions');
xlabel('x-axis');
ylabel('y-axis');
legend('Plot of h1','plot of g1')

The line specifically I need help with is:

plot(x_values,y_values,'b:',x_values,subs(g1,x_values),'r');

Adding in 'linewidth',2 here produces the error I mentioned before

plot(x_values,y_values,'b:','linewidth',2,x_values,subs(g1,x_values),'r');

Any help would be massively appreciated!

Answer 1

[Thorsten]

The help for plot states that

    "The X,Y pairs, or X,Y,S triples, can be followed by 
    parameter/value pairs to specify additional properties 
    of the lines."

But this is not true if you have multiple x, y values in one plot command. In this case you have to split them like

plot(x_values,y_values,'b:','linewidth',2)
hold on
plot(x_values,subs(g1,x_values),'r');

[Tom]

Thanks! got it working

Answer 2

[Robert Cumming]

If you split it over two plot commands it will work:

 plot(x_values,y_values,'b:','linewidth',2)
 plot(x_values,subs(g1,x_values),'r');

When passing in extra arguments - you cant then pass in other x, y pairs.