how do you program matlab to select a number that wasn't presented in the stimuli? 50/50 between presented and not presented numbers for the Sternberg Task

rng('Shuffle'), ([a b c d e]) a = randperm(10, 5)-1 %length(a) for k=1:length(a) clf;text(0.5,0.5, num2str(a(k)),'FontSize',75);axis off; pause(1) clf; end for x1 = randsample(a,1), pause(2) clf;text(0.5,0.5, num2str(x1),'Fontsize',75);axis off end

So far the code i am using only selects a number that was presented but not a number that wasn't. Can anyone please help me solve this problem?

Answer 1

[Amy]

Hi Michael,

If you look at the documentation for the randsample function, you will see the following:

" y = randsample(population,k) returns a vector of k values sampled uniformly at random, without replacement, from the values in the vector population. "

So this means when you write:

x1 = randsample(a,1)

'x1' will only ever be assigned a value from a. If you want 'x1' to be any value from 1 to 10, you would just replace 'a' with 10:

x1 = randsample(10,1)

[Michael Davies]

Hi Amy, thank you so much for your help!!