def test_lagfromroots(self) : res = lag.lagfromroots([]) assert_almost_equal(trim(res), [1]) for i in range(1, 5) : roots = np.cos(np.linspace(-np.pi, 0, 2*i + 1)[1::2]) pol = lag.lagfromroots(roots) res = lag.lagval(roots, pol) tgt = 0 assert_(len(pol) == i + 1) assert_almost_equal(lag.lag2poly(pol)[-1], 1) assert_almost_equal(res, tgt)
def test_lagfromroots(self): res = lag.lagfromroots([]) assert_almost_equal(trim(res), [1]) for i in range(1, 5): roots = np.cos(np.linspace(-np.pi, 0, 2 * i + 1)[1::2]) pol = lag.lagfromroots(roots) res = lag.lagval(roots, pol) tgt = 0 assert_(len(pol) == i + 1) assert_almost_equal(lag.lag2poly(pol)[-1], 1) assert_almost_equal(res, tgt)
def test_lag2poly(self) : for i in range(7) : assert_almost_equal(lag.lag2poly([0]*i + [1]), Llist[i])
def test_lagint(self) : # check exceptions assert_raises(ValueError, lag.lagint, [0], .5) assert_raises(ValueError, lag.lagint, [0], -1) assert_raises(ValueError, lag.lagint, [0], 1, [0, 0]) # test integration of zero polynomial for i in range(2, 5): k = [0]*(i - 2) + [1] res = lag.lagint([0], m=i, k=k) assert_almost_equal(res, [1, -1]) # check single integration with integration constant for i in range(5) : scl = i + 1 pol = [0]*i + [1] tgt = [i] + [0]*i + [1/scl] lagpol = lag.poly2lag(pol) lagint = lag.lagint(lagpol, m=1, k=[i]) res = lag.lag2poly(lagint) assert_almost_equal(trim(res), trim(tgt)) # check single integration with integration constant and lbnd for i in range(5) : scl = i + 1 pol = [0]*i + [1] lagpol = lag.poly2lag(pol) lagint = lag.lagint(lagpol, m=1, k=[i], lbnd=-1) assert_almost_equal(lag.lagval(-1, lagint), i) # check single integration with integration constant and scaling for i in range(5) : scl = i + 1 pol = [0]*i + [1] tgt = [i] + [0]*i + [2/scl] lagpol = lag.poly2lag(pol) lagint = lag.lagint(lagpol, m=1, k=[i], scl=2) res = lag.lag2poly(lagint) assert_almost_equal(trim(res), trim(tgt)) # check multiple integrations with default k for i in range(5) : for j in range(2, 5) : pol = [0]*i + [1] tgt = pol[:] for k in range(j) : tgt = lag.lagint(tgt, m=1) res = lag.lagint(pol, m=j) assert_almost_equal(trim(res), trim(tgt)) # check multiple integrations with defined k for i in range(5) : for j in range(2, 5) : pol = [0]*i + [1] tgt = pol[:] for k in range(j) : tgt = lag.lagint(tgt, m=1, k=[k]) res = lag.lagint(pol, m=j, k=list(range(j))) assert_almost_equal(trim(res), trim(tgt)) # check multiple integrations with lbnd for i in range(5) : for j in range(2, 5) : pol = [0]*i + [1] tgt = pol[:] for k in range(j) : tgt = lag.lagint(tgt, m=1, k=[k], lbnd=-1) res = lag.lagint(pol, m=j, k=list(range(j)), lbnd=-1) assert_almost_equal(trim(res), trim(tgt)) # check multiple integrations with scaling for i in range(5) : for j in range(2, 5) : pol = [0]*i + [1] tgt = pol[:] for k in range(j) : tgt = lag.lagint(tgt, m=1, k=[k], scl=2) res = lag.lagint(pol, m=j, k=list(range(j)), scl=2) assert_almost_equal(trim(res), trim(tgt))
def test_lag2poly(self): for i in range(7): assert_almost_equal(lag.lag2poly([0] * i + [1]), Llist[i])
def test_lagint(self): # check exceptions assert_raises(ValueError, lag.lagint, [0], .5) assert_raises(ValueError, lag.lagint, [0], -1) assert_raises(ValueError, lag.lagint, [0], 1, [0, 0]) # test integration of zero polynomial for i in range(2, 5): k = [0] * (i - 2) + [1] res = lag.lagint([0], m=i, k=k) assert_almost_equal(res, [1, -1]) # check single integration with integration constant for i in range(5): scl = i + 1 pol = [0] * i + [1] tgt = [i] + [0] * i + [1 / scl] lagpol = lag.poly2lag(pol) lagint = lag.lagint(lagpol, m=1, k=[i]) res = lag.lag2poly(lagint) assert_almost_equal(trim(res), trim(tgt)) # check single integration with integration constant and lbnd for i in range(5): scl = i + 1 pol = [0] * i + [1] lagpol = lag.poly2lag(pol) lagint = lag.lagint(lagpol, m=1, k=[i], lbnd=-1) assert_almost_equal(lag.lagval(-1, lagint), i) # check single integration with integration constant and scaling for i in range(5): scl = i + 1 pol = [0] * i + [1] tgt = [i] + [0] * i + [2 / scl] lagpol = lag.poly2lag(pol) lagint = lag.lagint(lagpol, m=1, k=[i], scl=2) res = lag.lag2poly(lagint) assert_almost_equal(trim(res), trim(tgt)) # check multiple integrations with default k for i in range(5): for j in range(2, 5): pol = [0] * i + [1] tgt = pol[:] for k in range(j): tgt = lag.lagint(tgt, m=1) res = lag.lagint(pol, m=j) assert_almost_equal(trim(res), trim(tgt)) # check multiple integrations with defined k for i in range(5): for j in range(2, 5): pol = [0] * i + [1] tgt = pol[:] for k in range(j): tgt = lag.lagint(tgt, m=1, k=[k]) res = lag.lagint(pol, m=j, k=list(range(j))) assert_almost_equal(trim(res), trim(tgt)) # check multiple integrations with lbnd for i in range(5): for j in range(2, 5): pol = [0] * i + [1] tgt = pol[:] for k in range(j): tgt = lag.lagint(tgt, m=1, k=[k], lbnd=-1) res = lag.lagint(pol, m=j, k=list(range(j)), lbnd=-1) assert_almost_equal(trim(res), trim(tgt)) # check multiple integrations with scaling for i in range(5): for j in range(2, 5): pol = [0] * i + [1] tgt = pol[:] for k in range(j): tgt = lag.lagint(tgt, m=1, k=[k], scl=2) res = lag.lagint(pol, m=j, k=list(range(j)), scl=2) assert_almost_equal(trim(res), trim(tgt))
from numpy.polynomial.laguerre import lagroots, Laguerre,poly2lag,lag2poly import numpy as np p = np.poly1d([1, 1, 3, 2, -1, -3, -11, -8, -12, -4, 4]) roots = p.roots() p(-1.33826102e+01) print(p) for i in range(roots.size): print(p(roots[i])) print() p = n.poly1d([1, complex(0, 1), -1, complex(0, -1), 1]) roots = lagroots(p) print(p) for i in range(roots.size): print(roots[i]) pp=lag2poly(p) lagroots(pp) print (p)