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fix bug

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This commit is contained in:
Yu Cong
2025-10-19 23:48:01 +08:00
parent 7ff909307f
commit dd06bbec21
1 changed files with 9 additions and 8 deletions
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17
projection.sage
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@@ -30,13 +30,14 @@ def cogirthip(bases, integral=true):
cnt=0 # actual number of instances tested cnt=0 # actual number of instances tested
f = lambda g: g.is_connected() f = lambda g: g.is_connected()
for n in range(4,20): for N in range(8,20):
for g in filter(f, graphs(n)): for g in filter(f, graphs(N)):
A=g.incidence_matrix() A=g.incidence_matrix()
n,m = A.dimensions() n,m = A.dimensions()
# enumerate all vectors in F_2^n with even number of 1s # enumerate all vectors in F_2^n with even number of 1s
V = VectorSpace(GF(2), n) V = VectorSpace(GF(2), N)
for v in filter(lambda v: v.hamming_weight() % 2 == 0 and v!=0, V): for v in filter(lambda v: v.hamming_weight() % 2 == 0 and v!=0, V):
cnt=cnt+1
v_col=matrix(v).transpose() v_col=matrix(v).transpose()
A_t=A.augment(v_col) A_t=A.augment(v_col)
# print(A_t) # print(A_t)
@@ -46,9 +47,9 @@ for n in range(4,20):
strength=cogirthip(bases,integral=false) strength=cogirthip(bases,integral=false)
cogirth =cogirthip(bases,integral=true) cogirth =cogirthip(bases,integral=true)
gap = cogirth/strength gap = cogirth/strength
if gap > 2.01: if gap > 3.01:
print(f"bad example! gap={gap}") print(f"bad example! gap={gap}")
with open("projection.out", "a") as f: with open("projection.out", "a") as file:
f.write(str(gap)+"\n"+str(A_t)+"\n") file.write(str(gap)+"\n"+str(A_t)+"\n")
else: if cnt%100==0:
print(f"n={n},m={m},gap={gap}") print(f"#{cnt},n={n},m={m}")