Viewing Matlab Plot and Vectors in Workspace: A Guide for Beginners"

[kususe]

Ts=Nss:Nss:length(s);

hold on

plot(tv(Ts),fo(Ts),'or');

hold off

grid on

This is the last part of my Matlab macro.
I see that it creates a plot using two vectors called "tv" and "fo".
I would like to see the plot and this vectors too in my workspace on Matlab.
May I use a cycle?

Thank you in advance

 

[swraman]

If that is a subfunction and you want to access the variables outside of the function, you can jreturn them as an output variable.

An easier way to do it (that I think will fit your needs better) is by using the Figure you created to access the data. in Matlab, figures are like global variables, and you can access them and their properties in any workspace as long as you have access to the figure's handle (which is a double).

in the function, when you plot use:

p = plot(tv(Ts),fo(Ts),'or');

and return p as an output variable. you can now access the figure you created and its properties (including the tv and fo vectors) by using the appropriate figure commands. for example, to get tv from the plot with the handle p would be something like this:

get(p,'xdata');

 

[niyaz]

i have written the code for power vs time of a semiconductor laser for my homework. if i Fourier transform it...wdnt i get the pwer vs freq graph|?? how will i Fourier transform it??
i use y=fft(p) but i am not getting it...pleasez help...i have given the code

mmm=0;
for nW=[1 3 5]
mmm=mmm+1;
mm=0;
Lam=405e-9;
q=1.6e-19;
alpha=1.2;
Tn=3e-9;
Tp=6.5e-12;
G0=9.0e-6;
N0 = 1.2e15;
h=6.6e-34;
c=3e8;
Gamma=.208;
beta=4.0e-4;
epsilon=3.4e-17;
Va=10.64e-11;

for I =.1e-3:.1e-3:3.97e-3;


mm=mm+1;
tini=0;
tfin=7e-9;
dt=1e-12;
m=0;
N(1)=0;
S(1)=0;
D(1)=0;
for t=tini:dt:tfin
m=m+1;
delN=I/(q*Va)-N(m)/Tn-G0*(N(m)-N0)*S(m)/(1+epsilon*S(m));
delS=-S(m)/Tp+Gamma*beta*N(m)/Tn+Gamma*G0*(N(m)-N0)*S(m)/(1+epsilon*S(m));
delD=.5*alpha*(Gamma*(N(m)-N0)-(1/Tp));

N(m+1)=N(m)+dt*delN;
S(m+1)=S(m)+dt*delS;
D(m+1)=D(m)+dt*delD;
P(m+1)=1000*Va*S(m)*.85*h*c/(Lam*2*Gamma*Tp);
tt(m+1)=t;

end
II(mm)=I*1e3;
Po(mmm,mm)=sum(P(1:4000))/4000;
N1(mmm,mm)=sum(N(1:4000)/4000);
S1(mmm,mm)=sum(S(1:4000)/4000);
D1(mmm,mm)=sum(D(1:4000)/4000);


Po1(mmm,:)=P;
Nt(mmm,:)=N;
St(mmm,:)=S;
Dt(mmm,:)=D;
end
end



figure(3)
plot(tt,Po1);
xlabel('Time (ns)')
ylabel('Output power (mW)')
title('Output power Vs Time')

 

[swraman]

This should be in another thread, but there is a good example of fft code on hte mathworks website. I've used it many times and it works well,

http://www.mathworks.com/help/techdoc/ref/fft.html

 

[niyaz]

i did use that fft function . . but i don't get any results..i mean no graph...