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-rw-r--r-- | Lib/fnmatch.py | 35 | ||||
-rw-r--r-- | Lib/zmod.py | 94 |
2 files changed, 129 insertions, 0 deletions
diff --git a/Lib/fnmatch.py b/Lib/fnmatch.py new file mode 100644 index 0000000..c7caef6 --- /dev/null +++ b/Lib/fnmatch.py @@ -0,0 +1,35 @@ +# module 'fnmatch' -- filename matching with shell patterns + +# XXX [] patterns are not supported (but recognized) + +def fnmatch(name, pat): + if '*' in pat or '?' in pat or '[' in pat: + return fnmatch1(name, pat) + return name = pat + +def fnmatch1(name, pat): + for i in range(len(pat)): + c = pat[i] + if c = '*': + restpat = pat[i+1:] + if '*' in restpat or '?' in restpat or '[' in restpat: + for i in range(i, len(name)): + if fnmatch1(name[i:], restpat): + return 1 + return 0 + else: + return name[len(name)-len(restpat):] = restpat + elif c = '?': + if len(name) <= i : return 0 + elif c = '[': + return 0 # XXX + else: + if name[i:i+1] <> c: + return 0 + return 1 + +def fnmatchlist(names, pat): + res = [] + for name in names: + if fnmatch(name, pat): res.append(name) + return res diff --git a/Lib/zmod.py b/Lib/zmod.py new file mode 100644 index 0000000..d7f06db --- /dev/null +++ b/Lib/zmod.py @@ -0,0 +1,94 @@ +# module 'zmod' + +# Compute properties of mathematical "fields" formed by taking +# Z/n (the whole numbers modulo some whole number n) and an +# irreducible polynomial (i.e., a polynomial with only complex zeros), +# e.g., Z/5 and X**2 + 2. +# +# The field is formed by taking all possible linear combinations of +# a set of d base vectors (where d is the degree of the polynomial). +# +# Note that this procedure doesn't yield a field for all combinations +# of n and p: it may well be that some numbers have more than one +# inverse and others have none. This is what we check. +# +# Remember that a field is a ring where each element has an inverse. +# A ring has commutative addition and multiplication, a zero and a one: +# 0*x = x*0 = 0, 0+x = x+0 = x, 1*x = x*1 = x. Also, the distributive +# property holds: a*(b+c) = a*b + b*c. +# (XXX I forget if this is an axiom or follows from the rules.) + +import poly + + +# Example N and polynomial + +N = 5 +P = poly.plus(poly.one(0, 2), poly.one(2, 1)) # 2 + x**2 + + +# Return x modulo y. Returns >= 0 even if x < 0. + +def mod(x, y): + return divmod(x, y)[1] + + +# Normalize a polynomial modulo n and modulo p. + +def norm(a, n, p): + a = poly.modulo(a, p) + a = a[:] + for i in range(len(a)): a[i] = mod(a[i], n) + a = poly.normalize(a) + return a + + +# Make a list of all n^d elements of the proposed field. + +def make_all(mat): + all = [] + for row in mat: + for a in row: + all.append(a) + return all + +def make_elements(n, d): + if d = 0: return [poly.one(0, 0)] + sub = make_elements(n, d-1) + all = [] + for a in sub: + for i in range(n): + all.append(poly.plus(a, poly.one(d-1, i))) + return all + +def make_inv(all, n, p): + x = poly.one(1, 1) + inv = [] + for a in all: + inv.append(norm(poly.times(a, x), n, p)) + return inv + +def checkfield(n, p): + all = make_elements(n, len(p)-1) + inv = make_inv(all, n, p) + all1 = all[:] + inv1 = inv[:] + all1.sort() + inv1.sort() + if all1 = inv1: print 'BINGO!' + else: + print 'Sorry:', n, p + print all + print inv + +def rj(s, width): + if type(s) <> type(''): s = `s` + n = len(s) + if n >= width: return s + return ' '*(width - n) + s + +def lj(s, width): + if type(s) <> type(''): s = `s` + n = len(s) + if n >= width: return s + return s + ' '*(width - n) |