used ??= to cache image, coker, coimage

Macaulay2 · Oct 18, 2024 · 48c979d · 48c979d
1 parent b0c50d2
commit 48c979d
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Showing 2 changed files with 9 additions and 11 deletions.
diff --git a/M2/Macaulay2/m2/matrix1.m2 b/M2/Macaulay2/m2/matrix1.m2
@@ -416,15 +416,13 @@ Matrix#AfterPrint = Matrix#AfterNoPrint = f -> (
 
 -- precedence Matrix := x -> precedence symbol x
 
-image Matrix := Module => f -> (
-     if f.cache.?image then f.cache.image else f.cache.image = subquotient(f,)
-     )
-coimage Matrix := Module => f -> (
-     if f.cache.?coimage then f.cache.coimage else f.cache.coimage = cokernel inducedMap(source f, kernel f)
-     )
-cokernel Matrix := Module => m -> (
-     if m.cache.?cokernel then m.cache.cokernel else m.cache.cokernel = subquotient(,m)
-     )
+-- source and target are defined in modules.m2
+-- image caches f in M.cache.Monomials
+image    Matrix := Module => f -> f.cache.image    ??= subquotient(f, null)
+cokernel Matrix := Module => f -> f.cache.cokernel ??= subquotient(null, f)
+-- kernel is defined in pushforward.m2
+coimage  Matrix := Module => f -> f.cache.coimage  ??= cokernel inducedMap(source f, kernel f)
+-- homology is defined further down
 
 cokernel RingElement := Module => f -> cokernel matrix {{f}}
 image RingElement := Module => f -> image matrix {{f}}

diff --git a/M2/Macaulay2/m2/modules.m2 b/M2/Macaulay2/m2/modules.m2
@@ -15,8 +15,8 @@ ring Matrix := f -> (
      if R =!= S then error "expected module map with source and target over the same ring";
      if f.?RingMap then error "expected module map with no ring map";
      R)
-source Matrix := f -> f.source
-target Matrix := f -> f.target
+source Matrix := Module => f -> f.source
+target Matrix := Module => f -> f.target
 
 precision Matrix := precision @@ ring