Question

I have defined three variables a,b,c before a while loop, then compute a new var d.

I want to get rid of the biggest value in the three vars a,b,c and then replace it with d value; So I can keep the smallest values in the thre original vars.

a = 1;
b = 2;
c = 10;
While[ condition,

      compute d using  values of a b and c
      d = 4;      
      a = 1;
      b = 2;
      c = 4;  (*c = d *)


]

to do so I was think to get the max of the three vars and then update it depeneding wich has greatest value..

a = 1;
b = 2;
c = 10;
d = 4;
temp  = Max[a, b];
maxim = Max[c, temp];
a = a; (*did not change*)
b = b; (*did not change*)
c = d = 4 (*changed!!*)

So after that a new iteraion will occur and update the three vars…

Answer 1

Another option is as follows:

Clear@updateList
SetAttributes[updateList, HoldFirst]    
updateList[list_, value_] := 
     Module[{listMax = Max@list}, 
      list = (list /. listMax -> value);]

Now if I define variables as in your case and use the function:

a = 1; b = 10; c = 0;
updateList[{a,b,c},5];
{a,b,c}

Out[1]= {1, 5, 0}

You can see that the variable b, which was the largest has been replaced with the new value.