resolves #1744

Bump ModulePresentationsForCAP to v2025.06-01

Author: kamalsaleh

ModulePresentationsForCAP/PackageInfo.g

@@ -10,7 +10,7 @@ SetPackageInfo( rec(
 
 PackageName := "ModulePresentationsForCAP",
 Subtitle := "Category R-pres for CAP",
-Version := "2024.09-02",
+Version := "2025.06-01",
 Date := (function ( ) if IsBound( GAPInfo.SystemEnvironment.GAP_PKG_RELEASE_DATE ) then return GAPInfo.SystemEnvironment.GAP_PKG_RELEASE_DATE; else return Concatenation( ~.Version{[ 1 .. 4 ]}, "-", ~.Version{[ 6, 7 ]}, "-01" ); fi; end)( ),
 License := "GPL-2.0-or-later",
 

ModulePresentationsForCAP/gap/ModulePresentationsForCAP.gi

@@ -1088,20 +1088,11 @@ InstallGlobalFunction( ADD_LIFT_AND_COLIFT_LEFT,
     M := UnderlyingMatrix( Source( morphism_2 ) );
 
     v := NrColumns( M );
-       
+    
     s := NrColumns( P );
 
     N := UnderlyingMatrix( Range(  morphism_1 ) );
 
-    # NrColumns( N ) = 0 implies coker(N)=0 and  s = 0 implies coker(P)=0, hence morphism_1 is zero, and the zero morphism can always be lifted. 
-    if NrColumns( N ) = 0 or s = 0 then
-        return ZeroMorphism( Source( morphism_1 ), Source( morphism_2 ) ); 
-    fi;
-    
-    # if NrColumns(M)=0 then M is zero, hence lift exists iff morphism_1 is zero.
-    if NrColumns( M ) = 0 and IsZeroForMorphisms( morphism_1 ) then
-        return ZeroMorphism( Source( morphism_1 ), Source( morphism_2 ) );
-    fi;
     A := UnderlyingMatrix( morphism_1 );
 
     B := UnderlyingMatrix( morphism_2 );
@@ -1134,7 +1125,7 @@ InstallGlobalFunction( ADD_LIFT_AND_COLIFT_LEFT,
 
     fi;
 
-    vec_zero := HomalgZeroMatrix( NrRows( P )*NrColumns( M ), 1, homalg_ring );
+    vec_zero := HomalgZeroMatrix( NrRows( P )*NrColumns( M ), NrColumns( vec_A ), homalg_ring );
 
     vec := UnionOfRows( vec_A, vec_zero );
 
@@ -1195,21 +1186,11 @@ InstallGlobalFunction( ADD_LIFT_AND_COLIFT_LEFT,
     M := UnderlyingMatrix( Range( morphism_1 ) );
 
     v := NrColumns( M );
-       
+    
     s := NrColumns( I );
 
     N := UnderlyingMatrix( Source( morphism_1 ) );
 
-    # NrColumns( N ) = 0 implies coker(N)=0 and  s = 0 implies coker(I)=0, hence morphism_2 is zero, and the zero morphism can always be colifted.
-    if NrColumns( N ) = 0 or s = 0 then
-        return ZeroMorphism( Range( morphism_1 ), Range( morphism_2 ) );
-    fi;
-
-    # if NrColumns(M)=0 then M is zero, hence colift exists iff morphism_2 is zero.
-    if NrColumns( M ) = 0 and IsZeroForMorphisms( morphism_2 ) then
-        return ZeroMorphism( Range( morphism_1 ), Range( morphism_2 ) );
-    fi;
-
     B := UnderlyingMatrix( morphism_1 );
 
     A := UnderlyingMatrix( morphism_2 );
@@ -1231,7 +1212,7 @@ InstallGlobalFunction( ADD_LIFT_AND_COLIFT_LEFT,
     else
         vec := UnionOfRows( List( [ 1 .. NrColumns( A ) ], i-> CertainColumns( A_over_zero, [ i ] ) ) );
     fi;
-
+    
     return [ mat, vec ];
 
   end;
@@ -1314,14 +1295,6 @@ InstallGlobalFunction( ADD_LIFT_AND_COLIFT_RIGHT,
 
     Nt := TransposedMatrix( UnderlyingMatrix( Range(  morphism_1 ) ) );
 
-    if NrRows( Nt ) = 0 or s = 0 then
-        return ZeroMorphism( Source( morphism_1 ), Source( morphism_2 ) ); 
-    fi;
-
-    if NrRows( Mt ) = 0 and IsZeroForMorphisms( morphism_1 ) then
-        return ZeroMorphism( Source( morphism_1 ), Source( morphism_2 ) );
-    fi;
-
     At := TransposedMatrix( UnderlyingMatrix( morphism_1 ) );
 
     Bt := TransposedMatrix( UnderlyingMatrix( morphism_2 ) );
@@ -1354,7 +1327,7 @@ InstallGlobalFunction( ADD_LIFT_AND_COLIFT_RIGHT,
 
     fi;
 
-    vec_zero := HomalgZeroMatrix( NrRows( Pt )*NrColumns( Mt ), 1, homalg_ring );
+    vec_zero := HomalgZeroMatrix( NrRows( Pt )*NrColumns( Mt ), NrColumns( vec_A ), homalg_ring );
 
     vec := UnionOfRows( vec_A, vec_zero );