def randMatrix(r, c=None, min=0, max=99, seed=None, symmetric=False, percent=100):
"""Create random matrix with dimensions ``r`` x ``c``. If ``c`` is omitted
the matrix will be square. If ``symmetric`` is True the matrix must be
square. If ``percent`` is less than 100 then only approximately the given
percentage of elements will be non-zero.
Examples
========
>>> from sympy.matrices import randMatrix
>>> randMatrix(3) # doctest:+SKIP
[25, 45, 27]
[44, 54, 9]
[23, 96, 46]
>>> randMatrix(3, 2) # doctest:+SKIP
[87, 29]
[23, 37]
[90, 26]
>>> randMatrix(3, 3, 0, 2) # doctest:+SKIP
[0, 2, 0]
[2, 0, 1]
[0, 0, 1]
>>> randMatrix(3, symmetric=True) # doctest:+SKIP
[85, 26, 29]
[26, 71, 43]
[29, 43, 57]
>>> A = randMatrix(3, seed=1)
>>> B = randMatrix(3, seed=2)
>>> A == B # doctest:+SKIP
False
>>> A == randMatrix(3, seed=1)
True
>>> randMatrix(3, symmetric=True, percent=50) # doctest:+SKIP
[0, 68, 43]
[0, 68, 0]
[0, 91, 34]
"""
if c is None:
c = r
if seed is None:
prng = random.Random() # use system time
else:
prng = random.Random(seed)
if symmetric and r != c:
raise ValueError(
'For symmetric matrices, r must equal c, but %i != %i' % (r, c))
if not symmetric:
m = Matrix._new(r, c, lambda i, j: prng.randint(min, max))
else:
m = zeros(r)
for i in range(r):
for j in range(i, r):
m[i, j] = prng.randint(min, max)
for i in range(r):
for j in range(i):
m[i, j] = m[j, i]
if percent == 100:
return m
else:
z = int(r*c*percent // 100)
m._mat[:z] = [S.Zero]*z
random.shuffle(m._mat)
return m
def randMatrix(r, c=None, min=0, max=99, seed=None, symmetric=False, percent=100):
"""Create random matrix with dimensions ``r`` x ``c``. If ``c`` is omitted
the matrix will be square. If ``symmetric`` is True the matrix must be
square. If ``percent`` is less than 100 then only approximately the given
percentage of elements will be non-zero.
Examples
========
>>> from sympy.matrices import randMatrix
>>> randMatrix(3) # doctest:+SKIP
[25, 45, 27]
[44, 54, 9]
[23, 96, 46]
>>> randMatrix(3, 2) # doctest:+SKIP
[87, 29]
[23, 37]
[90, 26]
>>> randMatrix(3, 3, 0, 2) # doctest:+SKIP
[0, 2, 0]
[2, 0, 1]
[0, 0, 1]
>>> randMatrix(3, symmetric=True) # doctest:+SKIP
[85, 26, 29]
[26, 71, 43]
[29, 43, 57]
>>> A = randMatrix(3, seed=1)
>>> B = randMatrix(3, seed=2)
>>> A == B # doctest:+SKIP
False
>>> A == randMatrix(3, seed=1)
True
>>> randMatrix(3, symmetric=True, percent=50) # doctest:+SKIP
[0, 68, 43]
[0, 68, 0]
[0, 91, 34]
"""
if c is None:
c = r
if seed is None:
prng = random.Random() # use system time
else:
prng = random.Random(seed)
if symmetric and r != c:
raise ValueError(
'For symmetric matrices, r must equal c, but %i != %i' % (r, c))
if not symmetric:
m = Matrix._new(r, c, lambda i, j: prng.randint(min, max))
else:
m = zeros(r)
for i in range(r):
for j in range(i, r):
m[i, j] = prng.randint(min, max)
for i in range(r):
for j in range(i):
m[i, j] = m[j, i]
if percent == 100:
return m
else:
z = int(r*c*percent // 100)
m._mat[:z] = [S.Zero]*z
prng.shuffle(m._mat)
return m
