# Please help me in generating a random string(row vector) in which each element has a different upper bound.

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MANISH KUMAR on 23 Feb 2017
Edited: Massimo Zanetti on 23 Feb 2017
For example, I want to generate a row vector A randomly
A = [ 4 2 6 1 5 ];
Whose elements are bounded by an upper bound
UB = [ 5 4 6 3 5 ]
E.g. the first element of A can take any integer value between [0 – 5] and second element can take any integer value [0 – 4] and similarly other elements are bounded.
Now from this row vector 'A', N (length (A)), new vectors are to be generated. In each vector, an element of the vector A changes the value randomly within the upper bound and rest of the elements remains same. For example, for above vector A
A = [ 4 2 6 1 5 ];
New vectors are
A1 = [ 3 2 6 1 5 ];
A2 = [ 4 1 6 1 5 ];
A3 = [ 4 2 3 1 5 ];
A4 = [ 4 2 6 3 5 ];
A5 = [ 4 2 6 1 2 ];

Massimo Zanetti on 23 Feb 2017
Edited: Massimo Zanetti on 23 Feb 2017
The useful way is
U = [2,3,4,5,7];
A = arrayfun( @(x) randi([0,x]) , U )
but, if upper-bounds are 1-digit numbers, you can lighten the procedure by generating one random integer between 0 and N, where N is the number obtained by merging your 1-digit upper bounds. An example:
U = [5,4,6,8,6];
%merge digits
N = str2double(char(U+'0'))
%get random number between 0 and N
An = randi([0,N])
%get a vector of An digits
A = num2str(An)-'0'
N =
54686
An =
34015
A =
[3 4 0 1 5]
NOTES:
1. this only works if upper-bounds are 1-digit numbers!
2. you must treat appropriately leading zeros in A, e.g., if
A = [2,3,4]
you must get to
A = [0,0,2,3,4]