Hi guys, I need a lil help,please

I am writing a piece of code using for loop and if -elseif statments to get 4 different curves with different parameters all plotting on the same graph but it seems that matlab doesn't see the different parameters values. I only got 4 curves on each other with no change.

figure
xlim([-40 100])
ylim ([0 100])
for ii=1:4;                                                
if ii == 1 
theta=30;
FOV=50;
color = 'k';
style = '-';
hold on
elseif ii == 2    
theta=40;
FOV=40;
color = 'r';
style = '-.';
hold on
elseif ii == 3   
theta=50;
FOV=30;  
color = 'm';
style = '--';
hold on
elseif ii == 4    
theta=60;
FOV=20; 
color = 'b';
style = ':';  
end
set(gca,'XTick',[0 20]);
set(gca,'YTICK',[0 20 40]);
plot(x ,SNR_db,'Color',color,'LineStyle',style );
lgd = legend( 'thetad 30,FOVd 50','thetad 40,FOVd 40','thetad 50,FOVd 30','thetad 60,FOVd 20');
end
hold off
xlabel('x[m]')
ylabel('SNR[dB]')
title('SNR distrbution at first lane')

I think I did something wrong but I don't know where.

Answer 1

[Catalytic]

Your loop is sending the same x and SNR_dB to the plot command in every iteration. The data you are plotting does not vary through the loop at all.

[ORION OMN]

Thanks for your replying. I know but I don't know how to fix it

These different values will make changes in too many equations, is that means that I should put all of them inside the for loop ?

[Catalytic]

I'm glad you got it working.

[Star Strider]

@ORION OMN —

You didn’t say what ‘SNR_db’ is. However, one way to incorporate the changes would be to create it as an anonymous function:

SNR_db = @(x,theta,FOV) ...;

then change the plot call to:

plot(x ,SNR_db(x,theta,FOV),'Color',color,'LineStyle',style );

This will plot with the appropriate parameters you set earlier in your code.

[ORION OMN]

Thanks for your replying, I got what you mean and I will give it a try.

[Star Strider]

My pleasure.