Here is a distance formula

zmodnz

The following is a distance formula for a metric/pseudometric space.

Please. Can anyone give me ANY insight whatsoever about it?
Nothing is too trivial for me...i.e...everything will help me a lot.

Or has anyone ever seen it before?
It seems so so simple!!
What the hell is it!!???


d = abs(x1) + abs(x2) + abs(y1) +abs(y2)


P1(x1,y1).....P2(x2, y2)......abs is absolute value