Exemplo n.º 1
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def test_w1d_2d_fit():

    x = numpy.linspace(-1, 1, 1000)
    c = numpy.array([[3, 0.2, 1, -1], [4, 0.4, 0.8, -0.8]])

    y = numpy.sum(
        [_c[:, None] * numpy.power(x, i)[None, :] for i, _c in enumerate(c.T)],
        axis=0)
    # Add noise
    y += numpy.random.normal(scale=0.01, size=y.size).reshape(y.shape)
    # Add in deviates
    indx = numpy.unique(numpy.random.randint(1000, size=10))
    y[0, indx] += numpy.random.normal(scale=10, size=len(indx))
    y[1, indx] += numpy.random.normal(scale=10, size=len(indx))
    # Weight all y vectors the same
    w = numpy.ones(x.shape, dtype=float)
    w[indx] = 0.

    c_nw = numpy.polynomial.legendre.legfit(x, y.T, 4)
    c = numpy.polynomial.legendre.legfit(x, y.T, 4, w=w)

    leg = Legendre1D(x, 4)
    _c_nw = leg.fit(y)
    _c = leg.fit(y, w=w)

    assert numpy.allclose(c_nw, _c_nw.T), 'Legendre1D fits should match numpy.'
    assert numpy.allclose(c,
                          _c.T), 'Weighted Legendre1D fits should match numpy.'
Exemplo n.º 2
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def test_locrej_2d_fit():

    x = numpy.linspace(-1, 1, 1000)
    c = numpy.array([[3, 0.2, 1, -1], [4, 0.4, 0.8, -0.8]])

    y = numpy.sum(
        [_c[:, None] * numpy.power(x, i)[None, :] for i, _c in enumerate(c.T)],
        axis=0)
    # Add noise
    sigma = 0.01
    y += numpy.random.normal(scale=sigma, size=y.size).reshape(y.shape) \
            * numpy.absolute(x)[None,:] * 5
    # Add in deviates
    outlier = numpy.unravel_index(
        numpy.unique(numpy.random.randint(y.size, size=20)), y.shape)
    offset = numpy.random.normal(scale=10, size=len(outlier[0]))
    indx = numpy.absolute(offset) > 10 * sigma
    outlier = (outlier[0][indx], outlier[1][indx])
    y[outlier] += offset[indx]

    leg = Legendre1D(x, 4)
    c, rej = leg.fit(y, rej_iter=-1, rej_win=51)

    # Rejected all the outliers?
    assert numpy.all(rej[outlier]), 'Should have rejected all the outliers'

    # Don't use a local sigma
    _c, _rej = leg.fit(y, rej_iter=-1)

    # Should reject more when not considering local sigma
    assert numpy.sum(_rej) > numpy.sum(
        rej), 'Should have rejected more when using global sigma'
Exemplo n.º 3
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def test_ew_glbrej_1d_fit():

    x = numpy.linspace(-1, 1, 1000)
    y = 3 + 0.2 * x + x * x - x * x * x

    # Add noise
    sigma = 0.01
    noise = numpy.random.normal(scale=sigma, size=x.size)
    err = numpy.full(y.shape, sigma, dtype=float)

    outlier = numpy.unique(numpy.random.randint(1000, size=10))
    offset = numpy.random.normal(scale=10., size=len(outlier))
    noise[outlier] = offset
    err[outlier] = 10.

    # Add noise including larger error
    y += noise

    leg = Legendre1D(x, 4)
    c, rej = leg.fit(y, err=err, rej_iter=-1)
    _c, _rej = leg.fit(y, rej_iter=-1)

    # Fewer points should be rejected when accounting for errors
    assert numpy.sum(_rej) > numpy.sum(rej), \
            'Should not have rejected as many points when accounting for error'
Exemplo n.º 4
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def test_locrej_1d_fit():

    x = numpy.linspace(-1, 1, 1000)
    y = 3 + 0.2 * x + x * x - x * x * x
    # Add noise
    sigma = 0.01
    y += numpy.random.normal(scale=sigma, size=x.size) * numpy.absolute(x) * 5
    # Add in deviates
    outlier = numpy.unique(numpy.random.randint(1000, size=10))
    offset = numpy.random.normal(scale=10, size=len(outlier))
    indx = numpy.absolute(offset) > 10 * sigma
    outlier = outlier[indx]
    y[outlier] += offset[indx]

    leg = Legendre1D(x, 4)
    c, rej = leg.fit(y, rej_iter=-1, rej_win=51)

    # Rejected all the outliers?
    assert numpy.all(rej[outlier]), 'Should have rejected all the outliers'

    # Don't use a local sigma
    _c, _rej = leg.fit(y, rej_iter=-1)

    # Should reject more when not considering local sigma
    assert numpy.sum(_rej) > numpy.sum(
        rej), 'Should have rejected more when using global sigma'

    # Don't use a local sigma and only one iteration
    _c, __rej = leg.fit(y, rej_iter=1)

    # Should reject more when allowed to continue until no more rejections
    assert numpy.sum(_rej) > numpy.sum(
        __rej), 'Should have rejected fewer in one iteration'
Exemplo n.º 5
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def test_w2d_2d_fit():

    x = numpy.linspace(-1, 1, 1000)
    c = numpy.array([[3, 0.2, 1, -1], [4, 0.4, 0.8, -0.8]])

    y = numpy.sum(
        [_c[:, None] * numpy.power(x, i)[None, :] for i, _c in enumerate(c.T)],
        axis=0)
    # Add noise
    y += numpy.random.normal(scale=0.01, size=y.size).reshape(y.shape)
    # Add in deviates
    indx = numpy.unravel_index(
        numpy.unique(numpy.random.randint(y.size, size=20)), y.shape)
    y[indx] += numpy.random.normal(scale=10, size=len(indx[0]))
    # Weight y vectors independently
    w = numpy.ones(y.shape, dtype=float)
    w[indx] = 0.

    c = numpy.zeros((y.shape[0], 5), dtype=float)
    for i in range(y.shape[0]):
        c[i] = numpy.polynomial.legendre.legfit(x, y[i], 4, w=w[i])

    leg = Legendre1D(x, 4)
    _c = leg.fit(y, w=w)

    assert numpy.allclose(c,
                          _c), 'Weighted Legendre1D fits should match numpy.'

    # Tests both the construction of the model and that the residuals
    # are close to the expectation from the noise added to the data
    # (i.e. is the fit good).
    resid = numpy.ma.std(
        numpy.ma.MaskedArray(y, mask=numpy.logical_not(w > 0)) - leg.model(_c))
    assert numpy.isclose(numpy.round(resid, decimals=2),
                         0.01), 'Residuals too large'
Exemplo n.º 6
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def test_glbrej_2d_fit():

    rng = numpy.random.default_rng(seed=8001)

    x = numpy.linspace(-1, 1, 1000)
    c = numpy.array([[3, 0.2, 1, -1], [4, 0.4, 0.8, -0.8]])

    y = numpy.sum(
        [_c[:, None] * numpy.power(x, i)[None, :] for i, _c in enumerate(c.T)],
        axis=0)
    # Add noise
    sigma = 0.01
    y += rng.normal(scale=sigma, size=y.size).reshape(y.shape)
    # Add in deviates
    outlier = numpy.unravel_index(numpy.unique(rng.integers(y.size, size=20)),
                                  y.shape)
    offset = rng.normal(scale=10, size=len(outlier[0]))
    indx = numpy.absolute(offset) > 10 * sigma
    outlier = (outlier[0][indx], outlier[1][indx])
    y[outlier] += offset[indx]

    leg = Legendre1D(x, 4)
    c, rej = leg.fit(y, rej_iter=-1)

    # Rejected all the outliers?
    assert numpy.all(rej[outlier]), 'Should have rejected all the outliers'
Exemplo n.º 7
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def test_1d_fit():
    x = numpy.linspace(-1, 1, 1000)
    y = 3 + 0.2 * x + x * x - x * x * x
    y += numpy.random.normal(scale=0.01, size=x.size)

    c = numpy.polynomial.legendre.legfit(x, y, 4)
    leg = Legendre1D(x, 4)
    _c = leg.fit(y)

    assert numpy.allclose(c, _c), 'Legendre1D should match numpy.'
Exemplo n.º 8
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def test_2d_fit():

    x = numpy.linspace(-1, 1, 1000)
    c = numpy.array([[3, 0.2, 1, -1], [4, 0.4, 0.8, -0.8]])

    y = numpy.sum(
        [_c[:, None] * numpy.power(x, i)[None, :] for i, _c in enumerate(c.T)],
        axis=0)
    y += numpy.random.normal(scale=0.01, size=y.size).reshape(y.shape)

    c = numpy.polynomial.legendre.legfit(x, y.T, 4)

    leg = Legendre1D(x, 4)
    _c = leg.fit(y)

    assert numpy.allclose(c, _c.T), 'Legendre1D should match numpy.'
Exemplo n.º 9
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def test_glbrej_1d_fit():

    x = numpy.linspace(-1, 1, 1000)
    y = 3 + 0.2 * x + x * x - x * x * x
    # Add noise
    sigma = 0.01
    y += numpy.random.normal(scale=sigma, size=x.size)
    # Add in deviates
    outlier = numpy.unique(numpy.random.randint(1000, size=10))
    offset = numpy.random.normal(scale=10, size=len(outlier))
    indx = numpy.absolute(offset) > 10 * sigma
    outlier = outlier[indx]
    y[outlier] += offset[indx]

    leg = Legendre1D(x, 4)
    c, rej = leg.fit(y, rej_iter=-1)

    # Rejected all the outliers?
    assert numpy.all(rej[outlier]), 'Should have rejected all the outliers'
Exemplo n.º 10
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def test_w1d_1d_fit():

    x = numpy.linspace(-1, 1, 1000)
    y = 3 + 0.2 * x + x * x - x * x * x
    # Add noise
    y += numpy.random.normal(scale=0.01, size=x.size)
    # Add in deviates
    indx = numpy.unique(numpy.random.randint(1000, size=10))
    y[indx] += numpy.random.normal(scale=10, size=len(indx))
    w = numpy.ones(y.shape, dtype=float)
    w[indx] = 0.

    c_nw = numpy.polynomial.legendre.legfit(x, y, 4)
    c = numpy.polynomial.legendre.legfit(x, y, 4, w=w)

    leg = Legendre1D(x, 4)
    _c_nw = leg.fit(y)
    _c = leg.fit(y, w=w)

    assert numpy.allclose(c_nw, _c_nw), 'Legendre1D fits should match numpy.'
    assert numpy.allclose(c,
                          _c), 'Weighted Legendre1D fits should match numpy.'