How can i get required number of sample from simulink to workspace?

I have a synchronous generator model and it runs for an interval 0 to 50 sec.Finally i get current output in three phase and the size of my current values passed is 1000001x1 but i can use only 1001x1 values for further calculation. How can i reduce the size from 1000001x1 to 1001x1 without any distortion in the current values

Answer 1

[dbmn]

There are multiple possible solutions to your question (with different results), but all of them will fail the "without any distortion" requirement.

• you can just take every 1000th element (bad if there is high frequency noise)

    new_var = sim_var(1:1000:end);

• do the same, but with a filter first (f.ex. moving average) - better for noise

    % create moving average    
    sim_var2 = movmean(sim_var,1000);
    % same as before
    new_var2 = sim_var2(1:1000:end);

attached is a little example to show your the differences between the first two approaches

• Interpolate the values in your postprocessing calculation using "interp1"
• choose a different Stepsize for Simulation (100001 sounds like fixed step) to get to 1001 points

[Harinee Kannan]

The method was useful but there is a heavy loss in data. Now am trying to make the process online so as the values from simulink comes out, I can process it without storing. Is there any procedure to make the simulation online?

Answer 2

[ES]

Resample the data.

For example,

>> a = zeros(1000001,1); % Some data
>> b = a(1:1000:end); % Take every 1000th data
>> size(b)

ans =

          1001           1