How to create a list/array of output from Simulation

I've got a simulation, and I want to somehow count the number of times I get the value V = 100 through all my simulations.

At the moment I'm only doing 5 simulations because I just want proof of concept really.

So I have:

for sim=1:nTrials
    SCS = [];
    C = 1:100; 
    msize = numel(C);
    Q = C(randperm(msize,100));
    S = Q(1:10);
    M = max(S);
    R = Q(11:100);

    if M==100
        V = R(1,90)
    else
        A = find(R>M,1);
        V = R(1,A)
    end
end

where I want SCS to be the list.

I've been trying to either

a) make a list of every value of V I get, then count it (the counting is doable)

or

b) make a list of times I've gotten the value 100, almost like a tally.

I think a) is probably easier, but I can never get it to work for every iteration. I've tried this a few ways and I'm not quite sure what I'm doing. I've tried adding:

if M==100
     V = R(1,90)
else
     A = find(R>M,1);
     V = R(1,A)
  if V==100
       SCS(nTrials) = V
  end
end

which outputs

V = 93

V = 100

SCS = 0 0 0 0 100

V = 94

V = 84

V = 98

SCS = []

>>

Or

if M==100
        V = R(1,90)
else
        A = find(R>M,1);
        V = R(1,A)
end
    
if V ==100
        SCS = [SCS;A];
end

which outputs

V = 93

V = 100

V = 94

V = 84

V = 98

SCS = []

Answer 1

[Voss]

"I want to somehow count the number of times I get the value V = 100"

OK:

count = 0;
nTrials = 5;
rng(11); % *
for sim=1:nTrials
    C = 1:100; 
    msize = numel(C);
    Q = C(randperm(msize,100));
    S = Q(1:10);
    M = max(S);
    R = Q(11:100);
    if M==100
        V = R(1,90)
    else
        A = find(R>M,1);
        V = R(1,A)
    end
    if V == 100
        count = count+1;
    end
end

V = 87

V = 93

V = 100

V = 91

V = 100

disp(count);

     2

If instead you want to keep track of which simulations generated V = 100 (not just how many):

SCS = [];
nTrials = 5;
rng(11); % *
for sim=1:nTrials
    C = 1:100; 
    msize = numel(C);
    Q = C(randperm(msize,100));
    S = Q(1:10);
    M = max(S);
    R = Q(11:100);
    if M==100
        V = R(1,90)
    else
        A = find(R>M,1);
        V = R(1,A)
    end
    if V == 100
        SCS = [SCS; sim];
    end
end

V = 87

V = 93

V = 100

V = 91

V = 100

disp(SCS);

     3
     5

Or if you want to keep track of which simulation generated V = 100 and where it was in R:

SCS = [];
nTrials = 5;
rng(11); % *
for sim=1:nTrials
    C = 1:100; 
    msize = numel(C);
    Q = C(randperm(msize,100));
    S = Q(1:10);
    M = max(S);
    R = Q(11:100);
    if M==100
        V = R(1,90)
    else
        A = find(R>M,1);
        V = R(1,A)
    end
    if V == 100
        SCS = [SCS; sim A];
    end
end

V = 87

V = 93

V = 100

V = 91

V = 100

disp(SCS);

     3    18
     5    11

(* The rng(11) is there so that the three different methods all operate on the same sequence of random numbers. You can leave it there for testing/debugging your code while you decide what it should do, but take it out when it's time to run real random simulations.)

[Lou]

Thank you!

If I want to run multiple values of RV and count V=100 for each value of RV how do I do this?

clear all

nTrials=5;
RV = [10,20,30,40,50,60,70,80,90]
K = 100-RV
NQ = RV+1


for RV = [10,20,30,40,50,60,70,80,90]
    for sim=1:nTrials
        C = 1:100; 
        msize = numel(C);
        Q = C(randperm(msize,100));
        S = Q(1:RV);
        M = max(S);
        R = Q(NQ:100);

        if M==100
            V = R(1,90)
        else
            A = find(R>M,1);
            V = R(1,A)
        end
    end
end

I can keep a running count and that's great, but I would like to know how many times when RV = 10 I get V=100, and then RV=20, and then RV=30 and so on.

I've tried swapping the for RV and for sim round but it still doesn't work.

I also tried adding individual bits but this doesn't seem to work either.

        if RV == 10
            if V==100
            count10 = count10+1;
            end
        end
        if RV == 20 
             if V==100
            count20 = count20+1;
             end
        end
        if RV == 30
            if V==100
            count30 = count30+1;
            end
       if RV == 40
            if V==100
            count40 = count40+1;
            end
       end

[Voss]

nTrials=5;
RV = [10,20,30,40,50,60,70,80,90];
K = 100-RV;
NQ = RV+1;

% make a vector of counts, one count for each element of RV:
count = zeros(1,numel(RV));

% you can move these out of the loop(s), since they don't depend on RV and
% are the same for each simulation run:
C = 1:100; 
msize = numel(C);

% loop over indexes, since you'll need to index NQ as well as RV:
for ii = 1:numel(RV)
    disp(['  RV = ' num2str(RV(ii))]);
    for sim=1:nTrials
        Q = C(randperm(msize,100));
        S = Q(1:RV(ii));
        M = max(S);
        R = Q(NQ(ii):100);
        if M==100
%             V = R(1,90)
            % You can't necessarily take the 90th element of R anymore,
            % e.g., if RV(ii) is 50 then R has 50 elements. I changed
            % it to take the last element of R. I don't know if this is
            % what you want to do.
            V = R(end)
        else
            A = find(R>M,1);
            V = R(1,A)
        end
        if V == 100
            count(ii) = count(ii)+1;
        end
    end
end

  RV = 10

V = 99

V = 96

V = 98

V = 98

V = 100

  RV = 20

V = 56

V = 100

V = 93

V = 100

V = 100

  RV = 30

V = 99

V = 100

V = 96

V = 99

V = 100

  RV = 40

V = 100

V = 88

V = 100

V = 100

V = 99

  RV = 50

V = 27

V = 86

V = 98

V = 1

V = 99

  RV = 60

V = 5

V = 100

V = 10

V = 97

V = 69

  RV = 70

V = 51

V = 42

V = 88

V = 99

V = 52

  RV = 80

V = 47

V = 12

V = 42

V = 92

V = 18

  RV = 90

V = 11

V = 100

V = 49

V = 12

V = 47

disp(count);

     1     3     2     3     0     1     0     0     1