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5.1.1 attrib
Syntax:
attrib ( name )
Type:
- none
Purpose:
- displays the attribute list of the object called name.
Example:
Syntax:
attrib ( name , string_expression )
Type:
- any
Purpose:
- returns the value of the attribute string_expression of the
variable name. If the attribute is not defined for this variable,
attrib returns the empty string.
Example:
Syntax:
attrib ( name, string_expression, expression )
Type:
- none
Purpose:
- sets the attribute string_expression of the variable name
to the value expression.
Example:
Remark:
- An attribute may be described by any string_expression. Some of these are
used by the kernel of SINGULAR and referred to as reserved attributes.
Non-reserved attributes may be used, however, in procedures and can
considerably speed up computations.
Reserved attributes:
- (isSB, isHomog are used by the kernel, the other are used by libraries)
isSB
- the standard basis property is set by all commands computing a standard
basis like
groebner , std , stdhilb etc.; used by lift , dim ,
degree , mult , hilb , vdim , kbase
isHomog
- the weight vector for homogeneous or quasihomogeneous ideals/modules
isCI
- complete intersection property
isCM
- Cohen-Macaulay property
rank
- set the rank of a module (see nrows)
withSB
- value of type ideal, resp. module, is std
withHilb
- value of type intvec is hilb(_,1) (see hilb)
withRes
- value of type list is a free resolution
withDim
- value of type int is the dimension (see dim)
withMult
- value of type int is the multiplicity (see mult)
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