def testLanczosFunction1D(self):
def basicLanczos1(x, n):
return sinc(x) * sinc(x / float(n))
errMsg = "{} = {} != {} for n={}, x={}, xOffset={}, xAdj={}"
for n in range(1, 5):
f = afwMath.LanczosFunction1D(n)
self.assertEqual(f.getOrder(), n)
for xOffset in (-10.0, 0.0, 0.05):
f.setParameters((xOffset, ))
g = f.clone()
for x in np.arange(-10.0, 10.1, 0.50):
xAdj = x - xOffset
predVal = basicLanczos1(xAdj, n)
msg = errMsg.format(
type(f).__name__, f(x), predVal, n, x, xOffset, xAdj)
self.assertFloatsAlmostEqual(f(x),
predVal,
msg=msg,
atol=self.atol,
rtol=None)
msg = errMsg.format(
type(g).__name__, g(x), predVal, n, x, xOffset,
xAdj) + "; clone"
self.assertFloatsAlmostEqual(g(x),
predVal,
msg=msg,
atol=self.atol,
rtol=None)
def testCast(self):
for instance in (afwMath.Chebyshev1Function1F(2),
afwMath.GaussianFunction1F(1.0),
afwMath.LanczosFunction1F(3),
afwMath.NullFunction1F(),
afwMath.PolynomialFunction1F(2)):
Class = type(instance)
base = instance.clone()
self.assertEqual(type(base), afwMath.Function1F)
derived = Class.cast(base)
self.assertEqual(type(derived), Class)
for instance in (afwMath.Chebyshev1Function1D(2),
afwMath.GaussianFunction1D(1.0),
afwMath.LanczosFunction1D(3),
afwMath.NullFunction1D(),
afwMath.PolynomialFunction1D(2)):
Class = type(instance)
base = instance.clone()
self.assertEqual(type(base), afwMath.Function1D)
derived = Class.cast(base)
self.assertEqual(type(derived), Class)
for instance in (afwMath.Chebyshev1Function2F(2),
afwMath.GaussianFunction2F(1.0, 1.0),
afwMath.DoubleGaussianFunction2F(1.0),
afwMath.LanczosFunction2F(3),
afwMath.NullFunction2F(),
afwMath.PolynomialFunction2F(2)):
Class = type(instance)
base = instance.clone()
self.assertEqual(type(base), afwMath.Function2F)
derived = Class.cast(base)
self.assertEqual(type(derived), Class)
for instance in (afwMath.Chebyshev1Function2D(2),
afwMath.GaussianFunction2D(1.0, 1.0),
afwMath.DoubleGaussianFunction2D(1.0),
afwMath.LanczosFunction2D(3),
afwMath.NullFunction2D(),
afwMath.PolynomialFunction2D(2)):
Class = type(instance)
base = instance.clone()
self.assertEqual(type(base), afwMath.Function2D)
derived = Class.cast(base)
self.assertEqual(type(derived), Class)
def testLanczosFunction1D(self):
"""A test for LanczosFunction1D"""
def basicLanczos1(x, n):
return sinc(x) * sinc(x / float(n))
for n in range(1, 5):
f = afwMath.LanczosFunction1D(n)
self.assertEquals(f.getOrder(), n)
for xOffset in (-10.0, 0.0, 0.05):
f.setParameters((xOffset, ))
g = f.clone()
# self.assertEquals(g.getOrder(), n)
for x in numpy.arange(-10.0, 10.1, 0.50):
xAdj = x - xOffset
predVal = basicLanczos1(xAdj, n)
if not numpy.allclose(predVal, f(x)):
self.fail("%s = %s != %s for n=%s, x=%s, xOffset=%s, xAdj=%s" % \
(type(f).__name__, f(x), predVal, n, x, xOffset, xAdj))
if not numpy.allclose(predVal, g(x)):
self.fail("%s = %s != %s for n=%s, x=%s, xOffset=%s, xAdj=%s; clone" % \
(type(g).__name__, g(x), predVal, n, x, xOffset, xAdj))