Assign random number in column if negative/positive

Hello everyone,

I have a simple Matlab table with the last column having positive and negative numbers. If the values are negative I want to create an additional table and assign random numbers from 4 to 14 and the rest with "0". If the values are positive I want to assign random numbers from 4 to 14 and the rest "0 " in an additional column. see the attached picture

Answer 1

[KSSV]

val = [1 5 -3 4 8 -6]' ;
C1 = zeros(size(val)) ;
idx = val<0 ;
C1(idx) = randsample(4:14,nnz(idx)) ;
T = table(val,C1)

[Anna Go]

Hey KSSV, thank you for your help. Unfortunately, the code doesn't work when I change idx = val>0. Do you know why?

[KSSV]

It works very much.....show me the code you tried.

[Anna Go]

load energy
whos -file energy

T = table(hour, demand,generation);
T.diffrow = demand - generation;

% insert column with random buy price
T.buydprice = zeros(size(generation)) ;
idx = T.diffrow<0 ;
T.buydprice(idx) = randsample(4:14,nnz(idx)) ;

% insert column with random sell price
T.sellprice = zeros(size(generation)) ;
idx = T.diffrow>0 ;
T.sellprice(idx) = randsample(4:14,nnz(idx)) ;

disp(T)

I attached the .mat file. Thank you