from __future__ import division, absolute_import, print_function

from numpy import (logspace, linspace, dtype, array, finfo, typecodes, arange,
                   isnan)
from numpy.testing import (
    TestCase, run_module_suite, assert_, assert_equal, assert_raises,
    assert_array_equal
)


class TestLogspace(TestCase):

    def test_basic(self):
        y = logspace(0, 6)
        assert_(len(y) == 50)
        y = logspace(0, 6, num=100)
        assert_(y[-1] == 10 ** 6)
        y = logspace(0, 6, endpoint=0)
        assert_(y[-1] < 10 ** 6)
        y = logspace(0, 6, num=7)
        assert_array_equal(y, [1, 10, 100, 1e3, 1e4, 1e5, 1e6])

    def test_dtype(self):
        y = logspace(0, 6, dtype='float32')
        assert_equal(y.dtype, dtype('float32'))
        y = logspace(0, 6, dtype='float64')
        assert_equal(y.dtype, dtype('float64'))
        y = logspace(0, 6, dtype='int32')
        assert_equal(y.dtype, dtype('int32'))


class TestLinspace(TestCase):

    def test_basic(self):
        y = linspace(0, 10)
        assert_(len(y) == 50)
        y = linspace(2, 10, num=100)
        assert_(y[-1] == 10)
        y = linspace(2, 10, endpoint=0)
        assert_(y[-1] < 10)
        assert_raises(ValueError, linspace, 0, 10, num=-1)

    def test_corner(self):
        y = list(linspace(0, 1, 1))
        assert_(y == [0.0], y)
        y = list(linspace(0, 1, 2.5))
        assert_(y == [0.0, 1.0])

    def test_type(self):
        t1 = linspace(0, 1, 0).dtype
        t2 = linspace(0, 1, 1).dtype
        t3 = linspace(0, 1, 2).dtype
        assert_equal(t1, t2)
        assert_equal(t2, t3)

    def test_dtype(self):
        y = linspace(0, 6, dtype='float32')
        assert_equal(y.dtype, dtype('float32'))
        y = linspace(0, 6, dtype='float64')
        assert_equal(y.dtype, dtype('float64'))
        y = linspace(0, 6, dtype='int32')
        assert_equal(y.dtype, dtype('int32'))

    def test_array_scalar(self):
        lim1 = array([-120, 100], dtype="int8")
        lim2 = array([120, -100], dtype="int8")
        lim3 = array([1200, 1000], dtype="uint16")
        t1 = linspace(lim1[0], lim1[1], 5)
        t2 = linspace(lim2[0], lim2[1], 5)
        t3 = linspace(lim3[0], lim3[1], 5)
        t4 = linspace(-120.0, 100.0, 5)
        t5 = linspace(120.0, -100.0, 5)
        t6 = linspace(1200.0, 1000.0, 5)
        assert_equal(t1, t4)
        assert_equal(t2, t5)
        assert_equal(t3, t6)

    def test_complex(self):
        lim1 = linspace(1 + 2j, 3 + 4j, 5)
        t1 = array([ 1.0+2.j,  1.5+2.5j,  2.0+3.j,  2.5+3.5j,  3.0+4.j])
        lim2 = linspace(1j, 10, 5)
        t2 = array([  0.0+1.j,   2.5+0.75j,   5.0+0.5j,   7.5+0.25j,  10.0+0.j])
        assert_equal(lim1, t1)
        assert_equal(lim2, t2)

    def test_physical_quantities(self):
        class PhysicalQuantity(float):
            def __new__(cls, value):
                return float.__new__(cls, value)

            def __add__(self, x):
                assert_(isinstance(x, PhysicalQuantity))
                return PhysicalQuantity(float(x) + float(self))
            __radd__ = __add__

            def __sub__(self, x):
                assert_(isinstance(x, PhysicalQuantity))
                return PhysicalQuantity(float(self) - float(x))

            def __rsub__(self, x):
                assert_(isinstance(x, PhysicalQuantity))
                return PhysicalQuantity(float(x) - float(self))

            def __mul__(self, x):
                return PhysicalQuantity(float(x) * float(self))
            __rmul__ = __mul__

            def __div__(self, x):
                return PhysicalQuantity(float(self) / float(x))

            def __rdiv__(self, x):
                return PhysicalQuantity(float(x) / float(self))

        a = PhysicalQuantity(0.0)
        b = PhysicalQuantity(1.0)
        assert_equal(linspace(a, b), linspace(0.0, 1.0))

    def test_denormal_numbers(self):
        # Regression test for gh-5437. Will probably fail when compiled
        # with ICC, which flushes denormals to zero
        for dt in (dtype(f) for f in typecodes['Float']):
            stop = finfo(dt).tiny * finfo(dt).resolution
            assert_(any(linspace(0, stop, 10, endpoint=False, dtype=dt)))

    def test_equivalent_to_arange(self):
        for j in range(1000):
            assert_equal(linspace(0, j, j+1, dtype=int),
                         arange(j+1, dtype=int))

    def test_retstep(self):
        y = linspace(0, 1, 2, retstep=True)
        assert_(isinstance(y, tuple) and len(y) == 2)
        for num in (0, 1):
            for ept in (False, True):
                y = linspace(0, 1, num, endpoint=ept, retstep=True)
                assert_(isinstance(y, tuple) and len(y) == 2 and
                        len(y[0]) == num and isnan(y[1]),
                        'num={0}, endpoint={1}'.format(num, ept))


if __name__ == "__main__":
    run_module_suite()
