How can plot every n-th element in a vector AND the last element?

Hello everyone,

i want to plot just every n-th vector element in a for-loop, to speed up the plot loading time.

But I need also the last element to be plotted.

For example:

%p = [1,2,3,...,100,102,102]
n = 10
for i=10:n:102
    k(i) = p(i)
    ... 
end

The vector should than look like this: [10,20,30,40,50,60,70,80,90,100,102].

Also it would be great if i could avoid the error because of index exceeding the array bounds.

Thank you in advance!

Answer 1

[James Tursa]

If you don't care about possibly overplotting that last point twice, then simply

n = 10;
result = [p(n:n:end) p(end)];

If you want to make sure that last point doesn't overplot, then add some logic to avoid it. E.g.,

if( mod(numel(p),n) )
    result = [p(n:n:end) p(end)];
else
    result = p(n:n:end);
end

[Felix Richter]

First of all, thanks for your answer!

Manipulating my result vector like this would take a good logic to be stable.

Do you know any other way to boost the plot speed, without manipulating the result vector?