Round to nearest ones place value ex ante

Please excuse me if this as been addressed/answered in a previous post, but I have not found a solution to this in my searches.

I am trying to round a number to certain ones place values that are unknown ex ante.

For example, the following value is unkown at first:

randi([3700 3705])

Now, once that number is known, I would like to know if the random number is closer to 3700 or 3705. In addition, the values of 3700 and 3705 are unkown at first as well.

Seems simple, but I'm struggling with this one, so any help is much appreciated!

Answer 1

[Eric Delgado]

Lim_down = 3700;
Lim_up   = 3706;

x = randi([Lim_down Lim_up])

x = 3704

Lim_center = mean([Lim_down, Lim_up]);

if     x < Lim_center; fprintf("Closer to %.0f", Lim_down);
elseif x > Lim_center; fprintf("Closer to %.0f", Lim_up);
else;                  fprintf("In between...");
end

Closer to 3706

Answer 2

[David Hill]

a=1400;
b=2600;
r=randi([a b]);
abs(r-a)<abs(r-b);

Answer 3

[Steven Lord]

theRange = [3700 3705];
x = randi(theRange, 10, 1);
closer = interp1(theRange, theRange, x, 'nearest');

Let's show the results in a table for easy interpretation.

results = table(x, closer, 'VariableNames', ["Generated Number", "Closer Endpoint"])

results = 10×2 table
    Generated Number    Closer Endpoint
    ________________    _______________

          3701               3700      
          3701               3700      
          3700               3700      
          3702               3700      
          3705               3705      
          3702               3700      
          3705               3705      
          3701               3700      
          3700               3700      
          3704               3705