How to plot portion of a vector in matlab?

Hi,

I am trying to plot a portion (from indis to length(vector)) of a vector (vector) in matlab using the following syntax:

plot(-vector(indis:length(vector))+1)

I don't know what indis will be, that's why my only option is to use indis in the plotting syntax. My issue is that matlab plots -vector(1:length(vector))+1 instead of plotting it as I demanded.

Please help me with this issue.

I would really appreciate your help.

Thanks.

[Azzi Abdelmalek]

What is indis ? What do you want to plot?

[MatlabFan]

indis is an integer, which value I don't know what it will be. I do know that is is an integer greater than 1 and less than length(vector). I am trying to plot 1-vector(indis:length(vector)).

Answer 1

[Shashank Prasanna]

The following piece of code must make things clearer: I make few modifications, Notice I plot with respect to 'x'. If you don't then MATLAB will always assume x = 1:length(vector)

% Create Data
x=0:0.1:2*pi;
vector = sin(0:0.1:2*pi);

% Plot everything
indis=1; 
plot(x(indis:length(vector)),-vector(indis:length(vector))+1,'r--'); 
axis([0 6 0 2])

hold on

% Plot from 20 onwards
indis=20; 
plot(x(indis:length(vector)),-vector(indis:length(vector))+1); 
axis([0 6 0 2])

[MatlabFan]

You guys are awesome. I just realized that I had skipped an important step in my code, causing it to not produce the output I expected.My algorithm was correct, I just missed a step. I guess it is because I did not get enough rest lately. But, I certainly appreciate you all, for being there and providing your help. Thanks.

[Chris]

Thnx! This helped me a lot!

Answer 2

[Azzi Abdelmalek]

v=1:100
plot(v(40:end))

[Azzi Abdelmalek]

You don't need length(vector). just write

y=1-vector(indis:end)
plot(y)

but you need to assign a value to indis

[MatlabFan]

You guys are awesome. I just realized that I had skipped an important step in my code, causing it to not produce the output I expected.My algorithm was correct, I just missed a step. I guess it is because I did not get enough rest lately. But, I certainly appreciate you all, for being there and providing your help. Thanks.