Subscript indices must either be real positive integers or logicals (Random rainfall hyetograph)

I am trying to create random precipitation pulses for a hydrological model. I generated sample sets for different climate but randomly sometimes it stops and shows this error massage.

Subscript indices must either be real positive integers or logicals.

Error in untitled3(line 30) tt(st(i):en(i),2)=P(i);

sample set is attached: sample.mat

The portion of code for this simulation is:

function [output]= Untitled3( sample,numSamples )

     Trav  = sample(:,1); % Rainfall duration pulse
     Pav   = sample(:,2); % Rainfall average intensity
     Tbav  = sample(:,3); % inter storm periods 
remove_sam_rows = [];
for k= 1:numSamples
disp(sprintf('########### Simulation #: %i', k));
    Fp = abs(rand(250, 1));
    Fr = abs(rand (250,1));
    Fb = abs(rand(250,1));

    P = abs(-Pav(k)*log(1-Fp));
    Tb = abs(-Tbav(k)*log(1-Fb));
    Tr = abs(-Trav(k)*log(1-Fr));
    Time = Tr+Tb;
    for i = 2:250;
        Time(i)=Time(i)+Time(i-1);
    end

    st = floor(Time-(Tr));
    st = int32(st);
    en = ceil(Time);
    en = int32(en);
    totalTime=6599;
    tt=zeros(totalTime,2);
    tt(:,1)=1:totalTime;

     for i=1:size(en);
      tt(st(i):en(i),2)=P(i);
     end 
    tt=tt(1:6599,:);
 end
 output = tt;

Where: Fp,Fr and Fb are random numbers for precipitation intensity, duration and interstorm period to generate pulses. P, Tb and Tr is the precipitation intensity, interstorm period and duration. Pav, Tbav and Trav is climate sampleset average precipitation intensity, interstorm period and duration. Time is total duration of time. st, en is start and end time of each precipitation pulse and tt is total time.

For example if : K = 1, Pav(k) = 0.06 cm/hr , Tbav = 56 hr, and Trav(k)= 5 hr. One can create rainfall hyetograph for climate k=1.

Can someone help we with this problem?

Answer 1

[Star Strider]

I didn’t run your code (I don’t have ‘k’), but the most likely cause is that ‘st’ or ‘en’ are negative or zero. The best way I’ve found to avoid this would be:

st = 1 + abs(floor(Time-(Tr)));
en = 1 + abs(ceil(Time));

or something similar, depending on how you want to use them. The idea is that neither variable is ever <=0.

[Shukran Sahaar]

Thank you very much Star Strider.

[Star Strider]

My pleasure.

Answer 2

[Image Analyst]

We can't run your code to try to duplicate the problem since you didn't supply enough values for those variables you mentioned. So, see the FAQ: http://matlab.wikia.com/wiki/FAQ#How_do_I_fix_the_error_.22Subscript_indices_must_either_be_real_positive_integers_or_logicals..22.3F