Suppose the notcher is black and the surrounding group white.
Below squared stones (): notch (n)
Circled stones (): legs (ab)
Cross marked (): hips (xy)
- The notcher has a notch of n spaces.
- The notcher has a left leg of length a and a right leg of length b. The legs are the (black) stones on the second line.
- The notcher has a degree of weakness, x on the left hip and y on the right hip:
- The letter W means that the hip is white (weak or an (angle) wedge),
- N means that the stone on the hip is absent (neutral),
- while S means that it is black (solid or strong).
We put this information into a code nabxy, where n, a, b take numerical values, and x and y can be either W, N or S.
The status of the notcher assumes no outside liberties and no escape threat (e.g. a descent that threatens to live and to escape). That would have to be covered by a second status in parentheses or the like.
The code is leg-normal if
- a < b or
- a = b and x <= y (W < N < S: weaker before stronger)
It is hip-normal if
- x < y or
- x = y and a <= b
Use leg-normal if you put up a page. Use hip-normal if you search in the Table of Notchers (that gives tables of reasonable size). A flip might be necessary: an exchange of a and b as well as x and y.
See Table of Notchers for lots of examples.