how to rectify the error Index exceeds matrix dimensions.?

i am doing real time plotting of my sensor output in matlab. How to rectify the above error.This is my code.

if true
  clc
clear all
close all
a=arduino('com13','uno');
a1_pin='D9';
tic;
i=0;
while (toc<inf)
  i=i+1;
  t(i)=toc;
  v(i)=readDigitalPin(a,'D2');
  plot(t,v,'b')
  axis([0 inf 0 3])
  pause(0.1)

if((v(i)-v(i+1)==1)) tic else d(i)=toc; end end

end

Answer 1

[Torsten]

When you enter the if-statement, v(i+1) does not yet exist because the array v is only constructed up to element v(i).

Best wishes

Torsten.

[prajwal prabhu]

how to rectify the above code???

[Torsten]

Rectify the error that v(i+1) is undefined within the if-statement.

That's the only thing I can tell since I don't know what you are trying to do in your code.

Best wishes

Torsten.