def test_default_background_issue_fit(clean_astro_ui):
    """Test issue #943 with fit

    See https://github.com/sherpa/sherpa/issues/943#issuecomment-696119982
    """

    ui.set_default_id('x')

    # use least-square as we don't really care about the fit
    ui.set_stat('leastsq')

    ui.load_arrays('x', [1, 2, 3, 4], [5, 4, 3, 4], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3, 4]), [1, 1, 0, 1])
    arf = ui.create_arf(np.asarray([0.1, 0.2, 0.3, 0.4]),
                        np.asarray([0.2, 0.3, 0.4, 0.5]))
    ui.set_arf(arf)
    bkg.set_arf(arf)
    ui.set_bkg(bkg)

    # The model being fitted is a constant to 1,1,0,1 for
    # the background, so that should be 0.75 / 0.1 (as the
    # bin width is constant), and for the source it is
    # 5,4,3,4 - <0.75> [here ignoring the bin-width],
    # so [4.25,3.25,2.25,3.25] -> 13 / 4 -> 3.25
    #
    ui.set_source(ui.const1d.mdl1)
    ui.set_bkg_source(ui.const1d.mdl2)

    # Prior to #943 this would give a confusing error.
    #
    ui.fit()
    assert mdl1.c0.val == pytest.approx(3.25 / 0.1)
    assert mdl2.c0.val == pytest.approx(0.75 / 0.1)
예제 #2
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def test_fake_pha_background_model(clean_astro_ui, reset_seed):
    """Check we can add a background component.

    See also test_fake_pha_basic.

    For simplicity we use perfect responses.
    """

    np.random.seed(27347)

    id = 'qwerty'
    channels = np.arange(1, 4, dtype=np.int16)
    counts = np.ones(3, dtype=np.int16)
    bcounts = 100 * counts

    ui.load_arrays(id, channels, counts, ui.DataPHA)
    ui.set_exposure(id, 100)
    ui.set_backscal(id, 0.1)

    bkg = ui.DataPHA('bkg', channels, bcounts, exposure=200, backscal=0.4)

    ebins = np.asarray([1.1, 1.2, 1.4, 1.6])
    elo = ebins[:-1]
    ehi = ebins[1:]
    arf = ui.create_arf(elo, ehi)
    rmf = ui.create_rmf(elo, ehi, e_min=elo, e_max=ehi)

    mdl = ui.create_model_component('const1d', 'mdl')
    mdl.c0 = 0
    bkgmdl = ui.create_model_component('const1d', 'mdl')
    bkgmdl.c0 = 2
    ui.set_source(id, mdl)
    ui.set_bkg(id, bkg)
    ui.set_bkg_source(id, bkgmdl)
    ui.set_arf(id, arf, bkg_id=1)
    ui.set_rmf(id, rmf, bkg_id=1)

    ui.fake_pha(id, arf, rmf, 1000.0, bkg='model')

    faked = ui.get_data(id)
    assert faked.exposure == pytest.approx(1000.0)
    assert (faked.channel == channels).all()

    # check we've faked counts (the scaling is such that it is
    # very improbable that this condition will fail)
    assert (faked.counts > counts).all()

    # For reference the predicted source signal is
    #    [200, 400, 400]
    # and the background signal is
    #    [125, 125, 125]
    # so, even with randomly drawn values, the following
    # checks should be robust.
    #
    predicted_by_source = 1000 * mdl(elo, ehi)
    predicted_by_bkg = (1000 / 200) * (0.1 / 0.4) * bcounts
    assert (faked.counts > predicted_by_source).all()
    assert (faked.counts > predicted_by_bkg).all()
def test_get_syserror_missing(bid):
    """Does get_syserror error out?"""

    ui.load_arrays(1, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(bkg)
    with pytest.raises(DataErr) as exc:
        ui.get_syserror(bkg_id=bid)

    assert str(exc.value) == "data set '1' does not specify systematic errors"
def test_set_filter_mismatch(f, bid):
    """Does set_filter error when there's a mis-match?
    """

    ui.load_arrays(1, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(bkg)
    with pytest.raises(DataErr) as exc:
        ui.set_filter(f, bkg_id=bid)

    assert str(exc.value) == 'size mismatch between 3 and 2'
def test_fix_background_id_error_checks2():
    """Check error handling of background id"""

    ui.load_arrays(2, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(2, bkg)

    with pytest.raises(IdentifierErr) as exc:
        ui.get_bkg_source(id=2, bkg_id='bkg')

    assert str(exc.value) == "identifier 'bkg' is a reserved word"
def test_fix_background_id_error_checks1():
    """Check error handling of background id"""

    ui.load_arrays(2, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(2, bkg)

    with pytest.raises(ArgumentTypeErr) as exc:
        ui.get_bkg_source(id=2, bkg_id=bkg)

    assert str(exc.value) == 'identifiers must be integers or strings'
def test_save_xxx_nodata(func, etype, emsg):
    """Does save_xxx error out if there's no data to save? DataPHA
    """

    ui.load_arrays(1, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(bkg)

    with pytest.raises(etype) as exc:
        func("temp-file-that-should-not-be-created")

    assert str(exc.value) == emsg
def test_save_image_nodata():
    """Does save_image error out if there's no data to save? DataPHA

    Unlike the other calls, this requires a FITS library
    """

    ui.load_arrays(1, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(bkg)

    with pytest.raises(IOErr) as exc:
        ui.save_image("temp-file-that-should-not-be-created")

    assert str(exc.value) == "data set '' does not contain an image"
def test_bkg_id_get_bkg_source(clean_astro_ui):
    """Check the error message when the background model has not been set (issue #943)"""

    ui.set_default_id('x')

    ui.load_arrays('x', [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(bkg)

    with pytest.raises(ModelErr) as exc:
        ui.get_bkg_source()

    assert str(
        exc.value) == 'background model 1 for data set x has not been set'
def test_save_xxx_bkg_nodata(func, etype, emsg):
    """Does save_xxx error out if there's no data to save? DataPHA + bkg

    Note that save_image does not support a bkg_id parameter so is
    not tested here.
    """

    ui.load_arrays(1, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(bkg)

    with pytest.raises(etype) as exc:
        func("temp-file-that-should-not-be-created", bkg_id=1)

    assert str(exc.value) == emsg
def test_save_filter_ignored(bid):
    """Does save_filter error out if everything is masked?

    We should be able to write out the filter in this case,
    as it's easy (all False).
    """

    ui.load_arrays(1, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(bkg)

    ui.ignore(None, None)

    with pytest.raises(DataErr) as exc:
        ui.save_filter("temp-file-that-should-not-be-created", bkg_id=bid)

    assert str(exc.value) == "mask excludes all data"
def test_set_filter_mismatch_with_filter(f, bid):
    """Does set_filter error when there's a mis-match after a filter?

    test_set_filter_mismatch checks when .mask is a scalar,
    so now check when it's a NumPy array.
    """

    ui.load_arrays(1, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(bkg)

    ui.ignore(3, None)  # set the .mask attribute to an array

    with pytest.raises(DataErr) as exc:
        ui.set_filter(f, bkg_id=bid)

    assert str(exc.value) == 'size mismatch between 3 and 2'
def test_delete_bkg_model_with_bkgid(id, clean_astro_ui):
    """Check we call delete_bkg_model with non-default bkg_id"""

    ui.load_arrays(id, [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    ui.set_bkg(id, bkg, bkg_id=2)

    ui.set_bkg_source(id, ui.const1d.bmdl, bkg_id=2)
    assert ui.list_model_components() == ['bmdl']
    assert ui.get_bkg_source(id, 2).name == 'const1d.bmdl'

    ui.delete_bkg_model(id, bkg_id=2)
    assert ui.list_model_components() == ['bmdl']

    with pytest.raises(ModelErr) as exc:
        ui.get_bkg_source(id, 2)

    emsg = 'background model 2 for data set {} has not been set'.format(id)
    assert str(exc.value) == emsg
def test_show_bkg_model_issue943(clean_astro_ui):
    """Test issue #943

    We do not check that show_bkg_model is creating anything
    useful, just that it can be called.

    See https://github.com/sherpa/sherpa/issues/943#issuecomment-696119982
    """

    ui.set_default_id('x')

    ui.load_arrays('x', [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    arf = ui.create_arf(np.asarray([0.1, 0.2, 0.3]),
                        np.asarray([0.2, 0.3, 0.4]))
    bkg.set_arf(arf)
    ui.set_bkg(bkg)

    ui.set_bkg_source(ui.const1d.mdl2)
    ui.show_bkg_model()
def test_default_background_issue(clean_astro_ui):
    """Test issue #943"""

    ui.set_default_id('x')

    # use least-square as we don't really care about the fit
    ui.set_stat('leastsq')

    ui.load_arrays('x', [1, 2, 3], [5, 4, 3], ui.DataPHA)
    bkg = ui.DataPHA('bkg', np.asarray([1, 2, 3]), [1, 1, 0])
    arf = ui.create_arf(np.asarray([0.1, 0.2, 0.3]),
                        np.asarray([0.2, 0.3, 0.4]))
    bkg.set_arf(arf)
    ui.set_bkg(bkg)

    ui.set_bkg_source(ui.const1d.mdl2)

    # Ensure we can fit the background model. Prior to #943 being
    # fixed the fit_bkg call would error out.
    #
    ui.fit_bkg()
    assert mdl2.c0.val == pytest.approx(2 / 3 / 0.1)
def test_subtract_already_subtracted(idval):
    """Does subtract still work if the data is already subtracted?"""

    x = [1, 2, 3]
    y = [0, 4, 3]
    ui.load_arrays('bgnd', x, y, ui.DataPHA)
    bkg = ui.get_data('bgnd')

    if idval is None:
        ui.load_arrays(1, x, y, ui.DataPHA)
        ui.set_bkg(bkg)
    else:
        ui.load_arrays(idval, x, y, ui.DataPHA)
        ui.set_bkg(idval, bkg)

    data = ui.get_data(idval)
    assert not data.subtracted

    ui.subtract(idval)
    assert data.subtracted

    ui.subtract(idval)
    assert ui.get_dep(idval) == pytest.approx([0, 0, 0])
예제 #17
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def test_fake_pha_basic(id, has_bkg, clean_astro_ui):
    """No background.

    See also test_fake_pha_add_background

    For simplicity we use perfect responses.

    A background dataset can be added, but it should
    not be used in the simulation.
    """

    channels = np.arange(1, 4, dtype=np.int16)
    counts = np.ones(3, dtype=np.int16)
    bcounts = 100 * counts

    ui.load_arrays(id, channels, counts, ui.DataPHA)
    ui.set_exposure(id, 100)

    if has_bkg:
        bkg = ui.DataPHA('bkg', channels, bcounts, exposure=200, backscal=0.4)
        ui.set_bkg(id, bkg, bkg_id='faked-bkg')

    ebins = np.asarray([1.1, 1.2, 1.4, 1.6])
    elo = ebins[:-1]
    ehi = ebins[1:]
    arf = ui.create_arf(elo, ehi)
    rmf = ui.create_rmf(elo, ehi, e_min=elo, e_max=ehi)

    mdl = ui.create_model_component('const1d', 'mdl')
    mdl.c0 = 2
    ui.set_source(id, mdl)

    ui.fake_pha(id, arf, rmf, 1000.0)

    faked = ui.get_data(id)
    assert faked.exposure == pytest.approx(1000.0)
    assert (faked.channel == channels).all()

    assert faked.name == 'faked'
    assert faked.get_arf().name == 'test-arf'
    assert faked.get_rmf().name == 'delta-rmf'

    if has_bkg and id is not None:
        assert faked.background_ids == ['faked-bkg']
        bkg = ui.get_bkg(id, 'faked-bkg')
        assert bkg.name == 'bkg'
        assert bkg.counts == pytest.approx(bcounts)
        assert bkg.exposure == pytest.approx(200)

    else:
        assert faked.background_ids == []

    # check we've faked counts (the scaling is such that it is
    # very improbable that this condition will fail)
    assert (faked.counts > counts).all()

    # For reference the predicted source signal is
    #    [200, 400, 400]
    #
    # What we'd like to say is that the predicted counts are
    # similar, but this is not easy to do. What we can try
    # is summing the counts (to average over the randomness)
    # and then a simple check
    #
    assert faked.counts.sum() > 200