示例#1
0
def test_clump_field_parameters():
    """
    Make sure clump finding on fields with field parameters works.
    """
    def _also_density(field, data):
        factor = data.get_field_parameter("factor")
        return factor * data["density"]

    ds = data_dir_load(i30)
    ds.add_field("also_density",
                 function=_also_density,
                 units=ds.fields.gas.density.units,
                 sampling_type="cell",
                 validators=[ValidateParameter("factor")])
    data_source = ds.disk([0.5, 0.5, 0.5], [0., 0., 1.], (8, 'kpc'),
                          (1, 'kpc'))
    data_source.set_field_parameter("factor", 1)

    step = 2.0
    field = ("gas", "density")
    c_min = 10**np.floor(np.log10(data_source[field]).min())
    c_max = 10**np.floor(np.log10(data_source[field]).max() + 1)

    master_clump_1 = Clump(data_source, ("gas", "density"))
    master_clump_1.add_validator("min_cells", 20)
    master_clump_2 = Clump(data_source, ("gas", "also_density"))
    master_clump_2.add_validator("min_cells", 20)

    find_clumps(master_clump_1, c_min, c_max, step)
    find_clumps(master_clump_2, c_min, c_max, step)
    leaf_clumps_1 = get_lowest_clumps(master_clump_1)
    leaf_clumps_2 = get_lowest_clumps(master_clump_2)

    for c1, c2 in zip(leaf_clumps_1, leaf_clumps_2):
        assert_array_equal(c1["gas", "density"], c2["gas", "density"])
示例#2
0
def test_clump_tree_save():
    tmpdir = tempfile.mkdtemp()
    curdir = os.getcwd()
    os.chdir(tmpdir)

    ds = data_dir_load(i30)
    data_source = ds.disk([0.5, 0.5, 0.5], [0., 0., 1.],
                          (8, 'kpc'), (1, 'kpc'))

    field = ("gas", "density")
    step = 2.0
    c_min = 10**np.floor(np.log10(data_source[field]).min()  )
    c_max = 10**np.floor(np.log10(data_source[field]).max()+1)

    master_clump = Clump(data_source, field)
    master_clump.add_info_item("center_of_mass")
    master_clump.add_validator("min_cells", 20)

    find_clumps(master_clump, c_min, c_max, step)
    leaf_clumps = get_lowest_clumps(master_clump)

    fn = master_clump.save_as_dataset(fields=["density", "x", "y", "z",
                                              "particle_mass"])
    ds2 = load(fn)

    # compare clumps in the tree
    t1 = [c for c in master_clump]
    t2 = [c for c in ds2.tree]
    mt1 = ds.arr([c.info["cell_mass"][1] for c in t1])
    mt2 = ds2.arr([c["clump", "cell_mass"] for c in t2])
    it1 = np.argsort(mt1).d.astype(int)
    it2 = np.argsort(mt2).d.astype(int)
    assert_array_equal(mt1[it1], mt2[it2])

    for i1, i2 in zip(it1, it2):
        ct1 = t1[i1]
        ct2 = t2[i2]
        assert_array_equal(ct1["gas", "density"],
                           ct2["grid", "density"])
        assert_array_equal(ct1["all", "particle_mass"],
                           ct2["all", "particle_mass"])

    # compare leaf clumps
    c1 = [c for c in leaf_clumps]
    c2 = [c for c in ds2.leaves]
    mc1 = ds.arr([c.info["cell_mass"][1] for c in c1])
    mc2 = ds2.arr([c["clump", "cell_mass"] for c in c2])
    ic1 = np.argsort(mc1).d.astype(int)
    ic2 = np.argsort(mc2).d.astype(int)
    assert_array_equal(mc1[ic1], mc2[ic2])

    os.chdir(curdir)
    shutil.rmtree(tmpdir)
示例#3
0
def test_clump_finding():
    n_c = 8
    n_p = 1
    dims = (n_c, n_c, n_c)

    density = np.ones(dims)
    high_rho = 10.
    # add a couple disconnected density enhancements
    density[2, 2, 2] = high_rho
    density[6, 6, 6] = high_rho

    # put a particle at the center of one of them
    dx = 1. / n_c
    px = 2.5 * dx * np.ones(n_p)

    data = {
        "density": density,
        "particle_mass": np.ones(n_p),
        "particle_position_x": px,
        "particle_position_y": px,
        "particle_position_z": px
    }

    ds = load_uniform_grid(data, dims)

    ad = ds.all_data()
    master_clump = Clump(ad, ("gas", "density"))
    master_clump.add_validator("min_cells", 1)

    find_clumps(master_clump, 0.5, 2. * high_rho, 10.)

    # there should be two children
    assert_equal(len(master_clump.children), 2)

    leaf_clumps = get_lowest_clumps(master_clump)
    # two leaf clumps
    assert_equal(len(leaf_clumps), 2)

    # check some clump fields
    assert_equal(master_clump.children[0]["density"][0].size, 1)
    assert_equal(master_clump.children[0]["density"][0], ad["density"].max())
    assert_equal(master_clump.children[0]["particle_mass"].size, 1)
    assert_array_equal(master_clump.children[0]["particle_mass"],
                       ad["particle_mass"])
    assert_equal(master_clump.children[1]["density"][0].size, 1)
    assert_equal(master_clump.children[1]["density"][0], ad["density"].max())
    assert_equal(master_clump.children[1]["particle_mass"].size, 0)
示例#4
0
def ytclumpfind_H2(ds, dd, field, n_cut, c_max=None, step=3, N_cell_min=10, save=False, plot=False, saveplot=False, fold_out='./'):
    '''

    The way it's implemented now only works for single "density" field.

    Parameter
    ---------
    ds: yt StreamDataset

    dd: YTRegion

    field: tuple
        tuple of str, e.g., ("gas", "density") or ("io", "....") or ("gas", "averaged_density"), etc... or just ("density") or ("stream", "density")

    n_cut: float or int
        defines lowest contour level to start searching from.
        e.g., density to cut the clouds.

    step: int
        multiplicative interval between subsequent contours

    N_cell_min: int
        min. number of cell s.t. clump identified is not spurious

    save: Boolean
        if true, save the clump tree as a reloadable dataset

    plot: Boolean
        if true, will plot leaf clump

    saveplot: boolean
        if true, will save figure instead of showing it

    fold_out: str
        directory to save figures


    Return
    ------
    master_clump: the top of a hierarchy of clumps
    leaf_clumps: list of individual clumps that have no children of their own


    '''

    if plot:
        assert saveplot is True

    # c_min = 10**np.floor(np.log10(dd[field]).min()  )
    # c_max = 10**np.floor(np.log10(dd[field]).max()+1)
    # if n_cut < 1.e-5:
    # n_cut = 1.0    # to make sure whatever comes out after multiplicative by
    # step won't be too small

    if step <= 1.0:
        step += 1
    c_min = n_cut

    if c_max is None:
        c_max = (dd[field]).max()

    # assert np.isnan(c_min) is False and np.isnan(c_max) is False
    print "min/max value for finding contours: ", c_min, c_max

    # this "base clump" just  covers the whole domain.
    master_clump = Clump(dd, field)
    # weed out clumps < N_cell_min cells.
    master_clump.add_validator("min_cells", N_cell_min)

    find_clumps(master_clump, c_min, c_max, step)

    if save:

        fn = master_clump.save_as_dataset(
            fields=list(field)),  # "particle_mass"])
        # # To reload the clump dataset
        # cds = yt.load(fn)
        # leaf_clumps_reloaded = cds.leaves

    # traverse clump hierarchy to get list of all 'leaf' clumps, which are the
    # individual clumps that have no children of their own
    leaf_clumps = get_lowest_clumps(master_clump)

    # print "printing sth here...", ds.tree["clump", field]
    # # *** AttributeError: 'StreamDataset' object has no attribute 'tree'

    if plot:
        plotclumps(ds=ds, leaf_clumps=leaf_clumps, field=field, master_clump=master_clump, saveplot=saveplot, fold_out=fold_out, n_cut=n_cut, N_cell_min=N_cell_min, step=step
                   )

    return master_clump, leaf_clumps