time shifting
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i want the program to advance or delay the signal... by taking input from user whether to advance or delay & by what number?.... please use switch statement?.... any signal like-ramp,step,exponential in it i am using subplot to plot the original signal & shifted version of the signal..
i have a program something like this--
*clear all
close all
clc
disp('given function is')
x=(-10:10);
for i=1:1:21
if(x(i)>0)
y(i)=exp(x(i));
else
y(i)=0;
end
end
subplot(1,2,1)
stem(x,y)
disp('enter whether to advance or delay')
s=input('1>advance\n 2>Delay')
n=input('enter the no of step by which signal is to be shifted')
switch(s)
case 1
[
for i=1+n:1:21+n
if(x(i)>0)
y(i)=1;
else
y(i)=0;
end
]
case 2
[
for i=1-n:1:21-n
if(x(i)>0)
y(i)=1;
else
y(i)=0;
end
]
subplot(1,2,2)
stem(x,y)
but when i run the program it gives error in the 'for' command in case 1.
3 Comments
Matt Tearle
on 20 Feb 2011
Can you please explain in more detail what you're trying to do? Do you have a time base vector t and a signal y(t) and you want the user to input a dt... and then do... what with it exactly?
Accepted Answer
Jan
on 21 Feb 2011
Omit the square brackets around the case blocks and close the SWITCH and IF blocks with an END.
switch(s)
case 1
for i=1+n:1:21+n
if(x(i)>0)
y(i)=1;
else
y(i)=0;
end
end
case 2
for i=1-n:1:21-n
if(x(i)>0)
y(i)=1;
else
y(i)=0;
end
end
end
More Answers (5)
Sk Group
on 8 Feb 2021
Edited: Sk Group
on 27 Oct 2021
For detailed post and complete code visit: https://www.swebllc.com/time-shifting-in-matlab-code-output/
0 Comments
Walter Roberson
on 21 Feb 2011
You cannot have an 'if' statement inside of [] . But you don't need to mark the beginning and end of the code for an individual case: all code is executed until the next 'case' or unmatched 'end'.
Matt Tearle
on 21 Feb 2011
On top of the syntax issues Walter and Jan point out...
1. Why use switch? You could easily use a simple if/|else|. But why not just flip the sign of the offset. Something like n = sign(1.5-s)*n
2. You can make the unshifted signal in a couple of lines:
y = exp(x);
y(x<=0) = 0;
3. What you have in the switches will cause an error because it will try to reference x(22) (or higher), but x only has 21 elements. What are you trying to do here? I would have thought that what you want mathematically is y(x+dx). In which case you could repeat the above lines with a shifted x:
x2 = x + dx;
y = exp(x2);
y(x2<=0) = 0;
Also, what you have there sets y to just 0 or 1, rather than 0 or exp(x). Was that what you intended?
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