Goto Chapter: Top 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Ind
 [Top of Book]  [Contents]   [Previous Chapter]   [Next Chapter] 

22 Meataxe modules
 22.1  

22 Meataxe modules

22.1  

22.1-1 DesuspensionMtxModule
‣ DesuspensionMtxModule( M )( function )

Inputs a meataxe module M over the field of p elements and returns an FpG-module DM. The two modules are related mathematically by the existence of a short exact sequence DM ⟶ FM ⟶ M with FM a free module. Thus the homological properties of DM are equal to those of M with a dimension shift.

(If G:=Group(M.generators) is a p-group then FM is a projective cover of M in the sense that the homomorphism FM ⟶ M does not factor as FM ⟶ P ⟶ M for any projective module P.)

Examples: 1 , 2 , 3 

22.1-2 FpG_to_MtxModule
‣ FpG_to_MtxModule( M )( function )

Inputs an FpG-module M and returns an isomorphic meataxe module.

Examples:

22.1-3 GeneratorsOfMtxModule
‣ GeneratorsOfMtxModule( M )( function )

Inputs a meataxe module M acting on, say, the vector space V. The function returns a minimal list of row vectors in V which generate V as a G-module (where G=Group(M.generators) ).

Examples:

 [Top of Book]  [Contents]   [Previous Chapter]   [Next Chapter] 
Goto Chapter: Top 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Ind

generated by GAPDoc2HTML