示例#1
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 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)
示例#2
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 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)
示例#3
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 def test_lag2poly(self) :
     for i in range(7) :
         assert_almost_equal(lag.lag2poly([0]*i + [1]), Llist[i])
示例#4
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    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))
示例#5
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 def test_lag2poly(self):
     for i in range(7):
         assert_almost_equal(lag.lag2poly([0] * i + [1]), Llist[i])
示例#6
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    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))
示例#7
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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)