GROEBRESTRICTION _ _ _ _ _ _ _ _ _ _ _ _ variable

During groebnerf calculations irrelevant branches can be excluded by setting the variable groebrestriction. The following restrictions are implemented:

syntax:

groebrestriction:= nonnegative

groebrestriction:= positive

groebrestriction:= zeropoint

With nonnegative branches are excluded where one polynomial has no nonnegative real zeros; with positive the restriction is sharpened to positive zeros only. The restriction zeropoint excludes all branches which do not have the origin (0,0,...0) in their solution set.