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5.1.76 lres

Syntax:
lres ( ideal_expression, int_expression )
Type:
resolution
Purpose:
computes a free resolution of an ideal using LaScala's algorithm.

More precisely, let R be the basering and I be the given ideal. Then lres computes a minimal free resolution of R/I If the int_expression k is not zero then the computation stops after k steps and returns a list of modules

list L=lres(I,0); returns a list L of n modules (where n is the number of variables of the basering) such that in the above notation.

Note:
The ideal_expression has to be homogeneous.
Accessing single elements of a resolution may require that some partial computations have to be finished and may therefore take some time.
Example:
 
See betti; hres; ideal; int; minres; module; mres; res; sres.

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            User manual for Singular version 3-1-6, Dec 2012, generated by texi2html.