def test_assert_raises_exceptions():
    ir = IsotonicRegression()
    rng = np.random.RandomState(42)
    assert_raises(ValueError, ir.fit, [0, 1, 2], [5, 7, 3], [0.1, 0.6])
    assert_raises(ValueError, ir.fit, [0, 1, 2], [5, 7])
    assert_raises(ValueError, ir.fit, rng.randn(3, 10), [0, 1, 2])
    assert_raises(ValueError, ir.transform, rng.randn(3, 10))
def test_isotonic_regression():
    y = np.array([3, 7, 5, 9, 8, 7, 10])
    y_ = np.array([3, 6, 6, 8, 8, 8, 10])
    assert_array_equal(y_, isotonic_regression(y))

    x = np.arange(len(y))
    ir = IsotonicRegression(y_min=0., y_max=1.)
    ir.fit(x, y)
    assert_array_equal(ir.fit(x, y).transform(x), ir.fit_transform(x, y))
    assert_array_equal(ir.transform(x), ir.predict(x))
def test_isotonic_regression():
    y = np.array([3, 7, 5, 9, 8, 7, 10])
    y_ = np.array([3, 6, 6, 8, 8, 8, 10])
    assert_array_equal(y_, isotonic_regression(y))

    x = np.arange(len(y))
    ir = IsotonicRegression(y_min=0., y_max=1.)
    ir.fit(x, y)
    assert_array_equal(ir.fit(x, y).transform(x), ir.fit_transform(x, y))
    assert_array_equal(ir.transform(x), ir.predict(x))

    # check that it is immune to permutation
    perm = np.random.permutation(len(y))
    ir = IsotonicRegression(y_min=0., y_max=1.)
    assert_array_equal(ir.fit_transform(x[perm], y[perm]), ir.fit_transform(x, y)[perm])
    assert_array_equal(ir.transform(x[perm]), ir.transform(x)[perm])
Exemple #4
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def test_isotonic_regression():
    y = np.array([3, 7, 5, 9, 8, 7, 10])
    y_ = np.array([3, 6, 6, 8, 8, 8, 10])
    assert_array_equal(y_, isotonic_regression(y))

    x = np.arange(len(y))
    ir = IsotonicRegression(y_min=0., y_max=1.)
    ir.fit(x, y)
    assert_array_equal(ir.fit(x, y).transform(x), ir.fit_transform(x, y))
    assert_array_equal(ir.transform(x), ir.predict(x))

    # check that it is immune to permutation
    perm = np.random.permutation(len(y))
    ir = IsotonicRegression(y_min=0., y_max=1.)
    assert_array_equal(ir.fit_transform(x[perm], y[perm]),
                       ir.fit_transform(x, y)[perm])
    assert_array_equal(ir.transform(x[perm]), ir.transform(x)[perm])
import numpy as np
import pylab as pl
from matplotlib.collections import LineCollection

from sklearn.linear_model import IsotonicRegression, LinearRegression
from sklearn.utils import check_random_state

n = 100
x = np.arange(n)
rs = check_random_state(0)
y = rs.randint(-50, 50, size=(n, )) + 50. * np.log(1 + np.arange(n))

###############################################################################
# Fit IsotonicRegression and LinearRegression models

ir = IsotonicRegression()
y_ = ir.fit_transform(x, y)

lr = LinearRegression()
lr.fit(x[:, np.newaxis], y)  # x needs to be 2d for LinearRegression

###############################################################################
# plot result

segments = [[[i, y[i]], [i, y_[i]]] for i in range(n)]
lc = LineCollection(segments, zorder=0)
lc.set_array(np.ones(len(y)))
lc.set_linewidths(0.5 * np.ones(n))

fig = pl.figure()
pl.plot(x, y, 'r.', markersize=12)
import numpy as np
import pylab as pl
from matplotlib.collections import LineCollection

from sklearn.linear_model import IsotonicRegression, LinearRegression
from sklearn.utils import check_random_state

n = 100
x = np.arange(n)
rs = check_random_state(0)
y = rs.randint(-50, 50, size=(n,)) + 50. * np.log(1 + np.arange(n))

###############################################################################
# Fit IsotonicRegression and LinearRegression models

ir = IsotonicRegression()
y_ = ir.fit_transform(x, y)

lr = LinearRegression()
lr.fit(x[:, np.newaxis], y)  # x needs to be 2d for LinearRegression

###############################################################################
# plot result

segments = [[[i, y[i]], [i, y_[i]]] for i in range(n)]
lc = LineCollection(segments, zorder=0)
lc.set_array(np.ones(len(y)))
lc.set_linewidths(0.5 * np.ones(n))

fig = pl.figure()
pl.plot(x, y, 'r.', markersize=12)