In his famous book "Combinatory Analysis" MacMahon introduced Partition Ana
lysis as a computational method for solving combinatorial problems in conne
ction with systems of linear diophantine inequalities and equations, Howeve
r, MacMahon failed in his attempt to use his method for a satisfactory trea
tment of plane partitions. It is the object of this article to show that ne
vertheless Partition Analysis is of significant value when treating non-sta
ndard types of plane partitions. To this end "plane partition diamonds" are
introduced, Applying Partition Analysis a simple closed form for the full
generating function is derived. In the discovering process the omega packag
e developed by the authors has played a fundamental role. (C) 2001 Academic
Press.