def test_arcsec_s(sinv):
def value(x):
return math.acos(1 / x)
output = ad.arcsec(sinv)
assert output.value == pytest.approx(value(sinv))
assert output.derivatives == {}
def test_arcsec_sm(minv):
def value(x):
return math.acos(1 / x)
output = ad.arcsec(minv)
for i in range(len(minv)):
assert output.value[i] == pytest.approx(value(minv[i]))
assert output.derivatives == {}
def test_arcsec_d(binv):
def value(x):
return math.acos(1 / x)
def der(x):
return 1 / (abs(x) * math.sqrt(x**2 - 1))
output = ad.arcsec(binv)
assert output.value == pytest.approx(value(binv.value))
coef = der(binv.value)
assert output.derivatives == pytest.approx({
'x': coef * 1.2,
'y': coef * 9.5,
'z': coef * 5
})
def test_arcsec_dm(dminv):
def value(x):
return math.acos(1 / x)
def der(x):
return 1 / (abs(x) * math.sqrt(x**2 - 1))
output = ad.arcsec(dminv)
for i in range(len(dminv.value)):
assert output.value[i] == pytest.approx(value(dminv.value[i]))
coef = der(dminv.value[i])
assert output.derivatives['x'][i] == pytest.approx(
coef * dminv.derivatives['x'][i])
assert output.derivatives['y'][i] == pytest.approx(
coef * dminv.derivatives['y'][i])
assert output.derivatives['z'][i] == pytest.approx(
coef * dminv.derivatives['z'][i])
def test_arcsec_no_change(binv):
b_d = binv.derivatives
output = ad.arcsec(binv)
assert b_d == binv.derivatives