Exemplo n.º 1
0
def rolling_fltr(dem, f=np.nanmedian, size=3, circular=True, origmask=False):
    """General rolling filter (default operator is median filter)

    Can input any function f

    Efficient for smaller arrays, correclty handles NaN, fills gaps
    """
    print("Applying rolling filter: %s with size %s" % (f.__name__, size))
    dem = malib.checkma(dem)
    #Convert to float32 so we can fill with nan
    dem = dem.astype(np.float32)
    newshp = (dem.size, size * size)
    #Force a step size of 1
    t = malib.sliding_window_padded(dem.filled(np.nan), (size, size), (1, 1))
    if circular:
        if size > 3:
            mask = circular_mask(size)
            t[:, mask] = np.nan
    t = t.reshape(newshp)
    out = f(t, axis=1).reshape(dem.shape)
    out = np.ma.fix_invalid(out).astype(dem.dtype)
    out.set_fill_value(dem.fill_value)
    if origmask:
        out = np.ma.array(out, mask=np.ma.getmaskarray(dem))
    return out
Exemplo n.º 2
0
def rolling_fltr(dem, f=np.nanmedian, size=3, circular=True):
    """General rolling filter (default operator is median filter)

    Can input any function f

    Efficient for smaller arrays, correclty handles NaN, fills gaps
    """
    dem = malib.checkma(dem)
    newshp = (dem.size, size*size)
    #Force a step size of 1
    t = malib.sliding_window_padded(dem.filled(np.nan), (size, size), (1, 1))
    if circular:
        mask = circular_mask(size)
        t[:,mask] = np.nan
    t = t.reshape(newshp)
    out = f(t, axis=1).reshape(dem.shape)
    out = np.ma.fix_invalid(out)
    out.set_fill_value(dem.fill_value)
    return out