如何缩放非常大的数字，以便它们可以表示为数组索引？

Question

I have a 2D array of size 30*70.

I have 70 columns. My values are very large ranging from 8066220960081 to (some number with same power of 10 as lowerlimit) and I need to plot a scatter plot in an array. How do I index into the array given very large values?

Also, I need to do this in kernel space

Answer 1

Let's take an array long long int A with large values.

A[0] = 393782040
A[1] = 2*393782040
... and so on
A[N] = 8066220960081; where N = 30*70 - 1

We can scale A with a factor or we can shift A by a certain number and scale it again. That's where you can deal with numbers ranging between 0 and 1 or -1 and 1 or x and y. You choose as per your need. Theoretically, this should not make a difference to the scatter plot other than the placement of the axis. However, if your scatter plot is also a representative of the underlying values ie the dots are proportional to values; then it is a good idea to be nice to your plotting tool and not flood it with terribly large values that might lead to overflow depending on how the code for plotting is written.

PS: I would assume you know how to flatten a 2d array.

Answer 2

I just ended up doing regular interval calculation between max and min and then start from min + interval*index to get the number. index would be the index in array.