Created
March 14, 2017 14:05
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Bruteforce matrix function relationships
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from sympy import * | |
import itertools | |
def M(a, f1, f2, f3, f4): | |
a1, a2, a3, a4 = a.values() | |
M1 = f1 * Matrix([[0,-a3, a2,0],[a3, 0, -a1,0],[-a2, a1, 0,0],[0,0,0,0]]) | |
M2 = f2 * Matrix([[0,0, 0,0],[0, 0, 0,0],[0, 0, 0,0],[a1,a2,a3,0]]) | |
M3 = f3 * Matrix([[0,0, 0,a1],[0, 0, 0,a2],[0, 0, 0,a3],[0,0,0,0]]) | |
M4 = f4 * a4 * eye(4) | |
return f1*M1 + f2*M2 + f3*M3 + f4*M4 | |
def W(a): | |
return M(a, -1,-1,1,1) | |
def Q(a): | |
return M(a, 1,-1,1,1) | |
def U(a): | |
return M(a, -1,1,1,-1) | |
def get_properties(expr,a,b): | |
Z = zeros(4) | |
it = list(itertools.product([-1,1],repeat=4)) | |
Ma = [M(a,i,j,k,l) for i,j,k,l in it] | |
Mb = [M(b,i,j,k,l) for i,j,k,l in it] | |
for f, F in enumerate(Ma): | |
for g, G in enumerate(Mb): | |
diff1 = expr - F*G | |
diff2 = expr - F*G.T | |
diff3 = expr - F.T*G | |
diff4 = expr - F.T*G.T | |
if diff1.equals(Z) or diff2.equals(Z) or diff3.equals(Z) or diff4.equals(Z): | |
i,j,k,l = it[f] | |
I,J,K,L = it[g] | |
if (i,j,k,l) == (-1,-1,1,1): | |
print "W", | |
elif (i,j,k,l) == (1,-1,1,1): | |
print "Q", | |
elif (i,j,k,l) == (-1,1,1,-1): | |
print "U", | |
else: | |
print (i,j,k,l), | |
if (I,J,K,L) == (-1,-1,1,1): | |
print "W", | |
elif (I,J,K,L) == (1,-1,1,1): | |
print "Q", | |
elif (I,J,K,L) == (-1,1,1,-1): | |
print "U", | |
else: | |
print (I,J,K,L) | |
if diff1.equals(Z): | |
print 1 | |
if diff2.equals(Z): | |
print 2 | |
if diff3.equals(Z): | |
print 3 | |
if diff4.equals(Z): | |
print 4 | |
a1, a2, a3, a4, b1, b2, b3, b4 = symbols('a1 a2 a3 a4 b1 b2 b3 b4') | |
a = Matrix([[a1,a2,a3,a4]]).T | |
b = Matrix([[b1,b2,b3,b4]]).T | |
for f1 in "Q","W","U": | |
if f1 == "Q": | |
A1 = Q | |
elif f1 == "W": | |
A1 = W | |
else: | |
A1 = U | |
for f2 in "Q","W","U": | |
if f2 == "Q": | |
B1 = Q | |
elif f2 == "W": | |
B1 = W | |
else: | |
B1 = U | |
for t1 in True,False: | |
for t2 in True,False: | |
for e1, e2 in ["aa","ab","ba"]: | |
if e1 == "a": | |
A2 = A1(a) | |
else: | |
A2 = A1(b) | |
if e2 == "a": | |
B2 = B1(a) | |
else: | |
B2 = B1(b) | |
if t1: | |
A3 = A2.T | |
else: | |
A3 = A2 | |
if t2: | |
B3 = B2.T | |
else: | |
B3 = B2 | |
print f1, f2, t1, t2, e1, e2 | |
get_properties(A3*B3, a, b) |
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