Sergio Basurto Juarez said: > First of all, I want to leave clear that I know that > the question that I am asking for, does not have to do > with this list, but I dare to ask this question here > because I am sure that here are a lot of good > programming and scientisitics guys and may be one of > you can help me. > > I am programming a function to search in an array, I > know there is the binarysearch algorithm, an other > good methods to search, but I want something that does > not take to long. > > my array is in the form like: > > myarray[1002] = 7507003101473; > myarray[1003] = 7507003101473; > myarray[1004] = 7507003101473; > myarray[1005] = 7507003101473; > myarray[1006] = 7507003101473; > myarray[1007] = 7507003101473; > myarray[1008] = 7507003101473; > myarray[1015] = 7507003101473; > myarray[1016] = 7507003101473; > myarray[1019] = 7507003101473; > . > . > . > myarray[8240] = 7507003182403; > > The array is formed dinamically from a file. > > I am wondering if there is some way to find a specific > value with a derivative method or something like that > . I found at www.nist.gov/dads/HTML and algorithm that > implements > the Newton Raphson method the formula is: > x0 = 0, x1= n-1, i = 1 and v is the array > > xi+1 = xi - (v[xi]-k) * (xi - xi-1)/(v[xi] - > v[xi-1]). > > but since the formula uses the values of the array > and the values that my array have are too big the > xi+1(the next indes) goes out of range. > > I will appreciate any help or point to a source of > information. > Newton Raphson is used to find an x-axis intercept (or a specific target value) of a function. I don't think it is quite suitable for your problem.
What I would do is create a hash table that will produce a near-unique ID for every element of the array. You can than use this key to find the exact element (or a small set of elements) in only few steps. Bojan -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
