# Whats wrong with this matlab code?

• MATLAB
Gold Member
I have a very simply matlab code. When I try go run it, I get no graph and switching over to the matlab command line, I see:
ans =

char

Here is the code:
Code:
t = linspace(0,60);
v = 3.22;

for q_0 = [0:1:2007];
q = q_0*exp(v*t);
plot(t,q)
hold on
end
It looks just fine to me.

Any feedback would be great.

chroot
Staff Emeritus
Gold Member
It runs fine in MATLAB R2006b on my computer.

Perhaps try removing the semicolon at the end of "for q_0 = [0:1:2007];"

- Warren

Gold Member
I still get no luck. I can run other m-files from the same directory with no problems. Does it say anything on the matlab command line when you run it?

I have copied-and-pasted the script on the Matlab (R11.1) command prompt and a figure appears. Nothing appears in the command line though.

How did you try to run the script?

Dr Transport
Gold Member
It looks to me to be plotting every point in a separate graph,, try writing to an array and plot after the loop is complete. I;ll try at work tommorow where I have Matlab R2006B.

Gold Member
I have copied-and-pasted the script on the Matlab (R11.1) command prompt and a figure appears. Nothing appears in the command line though.

How did you try to run the script?

I tried to run it from the m-file editor screen. The usual Debug>Run. I also even tried to get it from the command line, but I still get ans = char as an output.

Dr Transport said:
It looks to me to be plotting every point in a separate graph,, try writing to an array and plot after the loop is complete. I;ll try at work tommorow where I have Matlab R2006B.
I dont think its separate graphs. Its done on one graph but the "hold on" command allows me to plot different values for q_0 on the same graph.

Its is possible for anyone to post a screenshot of the graph? btw, I'm using R14.

Its is possible for anyone to post a screenshot of the graph? btw, I'm using R14.

Here's a screenshot...

#### Attachments

• 01.jpg
34 KB · Views: 347
Gold Member
Thanks doodle. It seems I have to do a little tweaking of my domain, but its what I expected it to be.

Gold Member
It turns out I was getting this error becuase the name of the M-file had a white space. Beats me...