Goto Chapter: Top 1 2 Ind
 [Top of Book]  [Contents]   [Previous Chapter]   [Next Chapter] 

1 Filters and constructors
 1.1 Filters
 1.2 Constructors
 1.3 Attributes and properties

1 Filters and constructors

1.1 Filters

1.1-1 IsQuotientCategory
‣ IsQuotientCategory( C )( filter )

Returns: a boolian

The Gap filter of the Cap quotient categories.

1.1-2 IsQuotientCategoryMorphism
‣ IsQuotientCategoryMorphism( alpha )( filter )

Returns: a boolian

The gap category of quotient categories morphisms

1.1-3 IsQuotientCategoryCell
‣ IsQuotientCategoryCell( a, object )( filter )

Returns: true or false

The GAP category of cells in the quotient category.

1.1-4 IsQuotientCategoryObject
‣ IsQuotientCategoryObject( a, object )( filter )

Returns: true or false

The GAP category of objects in the quotient category.

1.2 Constructors

1.2-1 QuotientCategory
‣ QuotientCategory( C, F )( operation )

Returns: a Cap category

The input is a category C and a function F. For two objects a and b in C, the function F can be applied on two morphisms \alpha,\beta \in \mathrm{Hom}_C(a,b) and returns true if \alpha \sim \beta and false otherwise. The output is the quotient category C/F.

1.2-2 QuotientCategoryMorphism
‣ QuotientCategoryMorphism( _a_, alpha, _b_ )( operation )

Returns: a morphism

The arguments are two objects \underline{a}, \underline{b} in a quotient category Q=C/F and a morphism \alpha:a \rightarrow b in C. The output is \underline{\alpha}: \underline{a} \rightarrow \underline{b} in Q.

1.2-3 QuotientCategoryMorphism
‣ QuotientCategoryMorphism( Q, alpha )( operation )

Returns: a morphism

The input is a quotient category Q=C/F and a morphism \alpha:a \rightarrow b in C. The output is \underline{\alpha}: \underline{a} \rightarrow \underline{b} in Q.

1.2-4 \/
‣ \/( Q, alpha )( operation )

Returns: a morphism

The input is a quotient category Q=C/F and a morphism \alpha:a \rightarrow b in C. The output is \underline{\alpha}: \underline{a} \rightarrow \underline{b} in Q.

1.2-5 QuotientCategoryObject
‣ QuotientCategoryObject( Q, a )( operation )

Returns: an object

The input is a quotient category Q=C/F and an object a \in C. The output is \underline{a} \in Q.

1.2-6 \/
‣ \/( a, Q )( operation )

Returns: an object

The input is a quotient category Q=C/F and an object a \in C. The output is \underline{a} \in Q.

1.3 Attributes and properties

1.3-1 UnderlyingCategory
‣ UnderlyingCategory( Q )( attribute )

Returns: a category

The input is a quotient category Q := C/F. The output is the category C.

1.3-2 CongruencyTestFunctionForQuotientCategory
‣ CongruencyTestFunctionForQuotientCategory( Q )( attribute )

Returns: a function

The input is a quotient category Q := C/F. The output is the congruence test function F.

1.3-3 ProjectionFunctor
‣ ProjectionFunctor( Q )( attribute )

Returns: a functor

The input is a quotient category Q := C/F. The output is the canonical projection functor \pi:C \rightarrow C/F.

1.3-4 UnderlyingCell
‣ UnderlyingCell( _alpha_ )( attribute )

Returns: a morphism

The input is a morphism \underline{\alpha}: \underline{a} \rightarrow \underline{b} in some quotient category Q=C/F and the output is \alpha: a \rightarrow b in C.

1.3-5 UnderlyingCell
‣ UnderlyingCell( _a_ )( attribute )

Returns: an object

The input is an object \underline{a} in some quotient category Q=C/F and the output is a in C.

 [Top of Book]  [Contents]   [Previous Chapter]   [Next Chapter] 
Goto Chapter: Top 1 2 Ind

generated by GAPDoc2HTML