dfsu.DfsuSpectral

dfsu.DfsuSpectral(self, filename)

Attributes

Name Description
deletevalue File delete value
directions Directional axis
end_time File end time
frequencies Frequency axis
geometry Geometry
items List of items
n_directions Number of directions
n_frequencies Number of frequencies
n_items Number of items
n_timesteps Number of time steps
start_time File start time
timestep Time step size in seconds

Methods

Name Description
calc_Hm0_from_spectrum Calculate significant wave height (Hm0) from spectrum
read Read data from a spectral dfsu file

calc_Hm0_from_spectrum

dfsu.DfsuSpectral.calc_Hm0_from_spectrum(spectrum, tail=True)

Calculate significant wave height (Hm0) from spectrum

Parameters

Name Type Description Default
spectrum (numpy.numpy.ndarray, mikeio.dataset.DataArray) frequency or direction-frequency spectrum required
tail bool Should a parametric spectral tail be added in the computations? by default True True

Returns

Type Description
numpy.numpy.ndarray significant wave height values

read

dfsu.DfsuSpectral.read(items=None, time=None, elements=None, nodes=None, area=None, x=None, y=None, keepdims=False, dtype=np.float32)

Read data from a spectral dfsu file

Parameters

Name Type Description Default
items Read only selected items, by number (0-based), or by name None
time Read only selected time steps, by default None (=all) None
keepdims When reading a single time step only, should the time-dimension be kept in the returned Dataset? by default: False False
area Read only data inside (horizontal) area (spectral area files only) given as a bounding box (tuple with left, lower, right, upper) or as list of coordinates for a polygon, by default None None
x Read only data for elements containing the (x,y) points(s), by default None None
y Read only data for elements containing the (x,y) points(s), by default None None
elements Read only selected element ids (spectral area files only) None
nodes Read only selected node ids (spectral line files only) None

Returns

Type Description
mikeio.dataset.Dataset A Dataset with dimensions [t,elements/nodes,frequencies,directions]

Examples

>>> mikeio.read("tests/testdata/line_spectra.dfsu")
<mikeio.Dataset>
dims: (time:4, node:10, direction:16, frequency:25)
time: 2017-10-27 00:00:00 - 2017-10-27 05:00:00 (4 records)
geometry: DfsuSpectral1D (9 elements, 10 nodes)
items:
  0:  Energy density <Wave energy density> (meter pow 2 sec per deg)
>>> mikeio.read("tests/testdata/area_spectra.dfsu", time=-1)
<mikeio.Dataset>
dims: (element:40, direction:16, frequency:25)
time: 2017-10-27 05:00:00 (time-invariant)
geometry: DfsuSpectral2D (40 elements, 33 nodes)
items:
  0:  Energy density <Wave energy density> (meter pow 2 sec per deg)