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-rw-r--r--src/algebra/cycles.spad.pamphlet26
1 files changed, 11 insertions, 15 deletions
diff --git a/src/algebra/cycles.spad.pamphlet b/src/algebra/cycles.spad.pamphlet
index 7b1b7c0d..0a92b83a 100644
--- a/src/algebra/cycles.spad.pamphlet
+++ b/src/algebra/cycles.spad.pamphlet
@@ -54,15 +54,15 @@ CycleIndicators: Exports == Implementation where
++\spad{alternating n} is the cycle index of the
++ alternating group of degree n.
- cyclic: PI -> SPOL RN --cyclic group
+ cyclic: NNI -> SPOL RN --cyclic group
++\spad{cyclic n} is the cycle index of the
++ cyclic group of degree n.
- dihedral: PI -> SPOL RN --dihedral group
+ dihedral: NNI -> SPOL RN --dihedral group
++\spad{dihedral n} is the cycle index of the
++ dihedral group of degree n.
- graphs: PI -> SPOL RN
+ graphs: NNI -> SPOL RN
++\spad{graphs n} is the cycle index of the group induced on
++ the edges of a graph by applying the symmetric function to the
++ n nodes.
@@ -100,24 +100,20 @@ CycleIndicators: Exports == Implementation where
trm: PTN -> SPOL RN
trm pt == monomial(inv(pdct(pt) :: RN),pt)
- list: Stream PTN -> L PTN
- list st == entries complete st
-
complete i ==
i=0 => 1
- +/[trm pt for pt in list partitions i]
-
-
- even?: PTN -> B
- even? p == even?( #([i for i in parts p | even? i]))
+ +/[trm pt for pt in entries partitions i]
+
+ even?: L I -> B
+ even? li == even?( #([i for i in li | even? i]))
alternating i ==
- 2 * _+/[trm p for p in list partitions i | even? p]
+ 2 * _+/[trm p for p in entries partitions i | even? p]
elementary i ==
i=0 => 1
- +/[(spol := trm pt; even? pt => spol; -spol)
- for pt in list partitions i]
+ +/[(spol := trm partition pt; even? pt => spol; -spol)
+ for pt in entries partitions i]
divisors: I -> L I
divisors n ==
@@ -161,7 +157,7 @@ CycleIndicators: Exports == Implementation where
prod := c * prod2 * prod
xx * prod
- graphs n == +/[trm2 p for p in list(partitions n)]
+ graphs n == +/[trm2 p for p in entries partitions n]
cupp: (PTN,SPOL RN) -> SPOL RN
cupp(pt,spol) ==