|  |  D.5.3.1 deRhamCohomology Procedure from librarydeRham.lib(see  deRham_lib).
 
Example:Usage:
deRhamCohomology(L[,choices]); L a list consisting of polynomials, choices
optional list consisting of one up to three strings The optional strings may be one of the strings
 -'noCE': compute quasi-isomorphic complexes without using Cartan-Eilenberg
resolutionsq
 -'Vdres': compute quasi-isomorphic complexes using Cartan-Eilenberg
resolutions; the CE resolutions are computed via V__d-homogenization
and without using Schreyer's method
 -'Sres': compute quasi-isomorphic complexes using Cartan-Eilenberg
resolutions in the homogenized Weyl algebra via Schreyer's method
 one of the strings
 -'iterativeloc': compute localizations by factorizing the polynomials and
successive localization of the factors
 -'no iterativeloc': compute localizations by directly localizing the
product
 and one of the strings
 -'onlybounds': computes bounds for the minimal and maximal integer roots
of the global b-function
 -'exactroots' computes the minimal and maximal integer root of the global
b-function
 The default is 'noCE', 'iterativeloc' and 'onlybounds'.
 
Assume:
-The basering must be a polynomial ring over the field of rational numbers
 
Return:
list, where the ith entry is the (i-1)st de Rham cohomology group of the
complement of the complex affine variety given by the polynomials in L
 |  | LIB "deRham.lib";
ring r = 0,(x,y,z),dp;
list L=(xy,xz);
deRhamCohomology(L);
==> [1]:
==>    1
==> [2]:
==>    1
==> [3]:
==>    0
==> [4]:
==>    1
==> [5]:
==>    1
 | 
 
 |