Diagonal matrix compression storage of a data structure

flcl_84

Which friend can answer? Convert an n-diagonal matrix matrix a [i] [j] (n = 1.2.3 ...) into a one-dimensional matrix sa [k]

  How to calculate the relationship between k and i, j?

  E.g. two diagonal matrix
    k = i + j-1
    But how did you get it?

  Thank you

flcl_84

up

zhoudaj

Well, this is so prescribed, there are not many reasons, just remember that k = i + j-1
This can save nearly half of the storage space.

cocoon_snow

Well, that's it, there is not much why, just remember that k = i+j-1
This saves nearly half of the storage space
This is not an answer