Moving between the condition

I am trying to replace an array values less than the orginal by generating random values between some range among them. I tried but the values are replaced by larger values than the orginal in some cases. So i have to use another condition to check this case and have to redo the random generation if the value goes greater than its original. I don't know how to jump again to the condition.Here is my code

 for i= 1 :x
     v = value(i);
    if(v>=min_value) && (v<=p10)
        rval = min_value + rand * (p10 - min_value);
      *if (rval<v)
             new(i,cnt+1) = rval;
          else*

    elseif (v>p10)  && (v<=p20)
        new(i,cnt+1) = p10+ rand * (p20 - p10);
  *if (rval<v)
             new(i,cnt+1) = rval;
       else*
         end
end

[Jan]

I cannot follow your description. Posting code, which does not do what you want, does not clear this also. Can you provide a short example of the inputs and the wanted outputs?

[Vennila Gangatharan]

Input array=>68,23,78,45,22,40,80

     Output array=> 62,22,70,43,21,34,69

This output should be generated randomly within intervals in which the value lies such as 1 to 20, 21 to 40, 41 to 60 and 61 to 80 and also less than it.

[Stephen23]

@Vennila Gangatharan: what relationship do those ranges have to the input values?

[Jan]

@Vennila Gangatharan: Although the readers might be able to guess a little bit, it is more reliable, if you explain carefully, what your code does and should do. What is "x", "value", "min_value", "p10", "p20"? Is "input array" the same as "value" and "output array" the same as "new"? You code looks like you want floating point values, but the data look like integer values. The less the reader has to guess, the more likely is that you get a matching answer.

If the input is 22, what is the allowed range for the output? Does the allowed range depend on the current input value only, or do other input or output values matter also?

Answer 1

[Image Analyst]

Try this for integers:

inputArray = [68,23,78,45,22,40,80]
minValue = min(inputArray)
maxValue = max(inputArray)
outputArray = randi([minValue, maxValue], 1, length(inputArray))

Try this for floating point:

inputArray = [68,23,78,45,22,40,80]
minValue = min(inputArray)
maxValue = max(inputArray)
outputArray = minValue + (maxValue - minValue) * rand(1, length(inputArray))

Answer 2

[Jan]

A bold guess: You want to choose a number between the next smaller multiple of 20 and the value. If so:

In  = [68,23,78,45,22,40,80];
Out = zeros(size(In));
for k = 1:numel(In)
  v      = In(k);
  low    = v - mod(v, 20) + 1;  % Or: floor(v / 20) * 20 + 1;
  high   = low + 19;
  Out(k) = randi([low, high]);
  % or:  = low + 20 * rand;  % Or 19 ?!
end

If this solves your problem, it can be vectorized easily for the floating point method:

    low    = In - mod(In, 20) + 1;
    Out(k) = low + 20 .* rand(size(In));