Skip to content

Numerics

Sub-commands to support the numerics components

BSBT

Bases: BaseSubComponent

BSBT first order propagation scheme.

.. code-block:: text

BSTB

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import BSBT
scheme = BSBT()
print(scheme.render())
Source code in rompy_swan/subcomponents/numerics.py 
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
class BSBT(BaseSubComponent):
    """BSBT first order propagation scheme.

    .. code-block:: text

        BSTB

    Examples
    --------

    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import BSBT
        scheme = BSBT()
        print(scheme.render())

    """

    model_type: Literal["bsbt", "BSBT"] = Field(
        default="bsbt", description="Model type discriminator"
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        return "BSBT"

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['bsbt', 'BSBT'] = Field(default='bsbt', description='Model type discriminator')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
34
35
36
def cmd(self) -> str:
    """Command file string for this component."""
    return "BSBT"

GSE

Bases: BaseSubComponent

Garden-sprinkler effect.

.. code-block:: text

GSE [waveage] Sec|MIn|HR|DAy

Garden-sprinkler effect is to be counteracted in the S&L propagation scheme (default for nonstationary regular grid computations) or in the propagation scheme for unstructured grids by adding a diffusion term to the basic equation. This may affect the numerical stability of SWAN.

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import GSE
scheme = GSE(waveage=dict(delt=86400, dfmt="day"))
print(scheme.render())
Source code in rompy_swan/subcomponents/numerics.py 
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
class GSE(BaseSubComponent):
    """Garden-sprinkler effect.

    .. code-block:: text

        GSE [waveage] Sec|MIn|HR|DAy

    Garden-sprinkler effect is to be counteracted in the S&L propagation scheme
    (default for nonstationary regular grid computations) or in the propagation
    scheme for unstructured grids by adding a diffusion term to the basic equation.
    This may affect the numerical stability of SWAN.

    Examples
    --------

    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import GSE
        scheme = GSE(waveage=dict(delt=86400, dfmt="day"))
        print(scheme.render())

    """

    model_type: Literal["gse", "GSE"] = Field(
        default="gse", description="Model type discriminator"
    )
    waveage: Optional[Delt] = Field(
        default=None,
        description=(
            "The time interval used to determine the diffusion which counteracts the "
            "so-called garden-sprinkler effect. The default value of `waveage` is "
            "zero, i.e. no added diffusion. The value of `waveage` should correspond "
            "to the travel time of the waves over the computational region."
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "GSE"
        if self.waveage is not None:
            repr += f" waveage={self.waveage.render()}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['gse', 'GSE'] = Field(default='gse', description='Model type discriminator')

waveage class-attribute instance-attribute 

waveage: Optional[Delt] = Field(default=None, description='The time interval used to determine the diffusion which counteracts the so-called garden-sprinkler effect. The default value of `waveage` is zero, i.e. no added diffusion. The value of `waveage` should correspond to the travel time of the waves over the computational region.')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
76
77
78
79
80
81
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "GSE"
    if self.waveage is not None:
        repr += f" waveage={self.waveage.render()}"
    return repr

STAT

Bases: BaseSubComponent

Computation parameters in stationary computation.

Source code in rompy_swan/subcomponents/numerics.py 
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
class STAT(BaseSubComponent):
    """Computation parameters in stationary computation."""

    model_type: Literal["stat", "STAT"] = Field(
        default="stat", description="Model type discriminator"
    )
    mxitst: Optional[int] = Field(
        default=None,
        description=(
            "The maximum number of iterations for stationary computations. The "
            "computation stops when this number is exceeded (SWAN default:  50)"
        ),
    )
    alfa: Optional[float] = Field(
        default=None,
        description=(
            "Proportionality constant used in the frequency-dependent under-"
            "relaxation technique. Based on experiences, a suggestion for this "
            "parameter is `alfa = 0.01`. In case of diffraction computations, the use "
            "of this parameter is recommended (SWAN default: 0.00)"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "STATIONARY"
        if self.mxitst is not None:
            repr += f" mxitst={self.mxitst}"
        if self.alfa is not None:
            repr += f" alfa={self.alfa}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['stat', 'STAT'] = Field(default='stat', description='Model type discriminator')

mxitst class-attribute instance-attribute 

mxitst: Optional[int] = Field(default=None, description='The maximum number of iterations for stationary computations. The computation stops when this number is exceeded (SWAN default:  50)')

alfa class-attribute instance-attribute 

alfa: Optional[float] = Field(default=None, description='Proportionality constant used in the frequency-dependent under-relaxation technique. Based on experiences, a suggestion for this parameter is `alfa = 0.01`. In case of diffraction computations, the use of this parameter is recommended (SWAN default: 0.00)')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
107
108
109
110
111
112
113
114
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "STATIONARY"
    if self.mxitst is not None:
        repr += f" mxitst={self.mxitst}"
    if self.alfa is not None:
        repr += f" alfa={self.alfa}"
    return repr

NONSTAT

Bases: BaseSubComponent

Computation parameters in nonstationary computation.

Source code in rompy_swan/subcomponents/numerics.py 
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
class NONSTAT(BaseSubComponent):
    """Computation parameters in nonstationary computation."""

    model_type: Literal["nonstat", "NONSTAT"] = Field(
        default="nonstat", description="Model type discriminator"
    )
    mxitns: Optional[int] = Field(
        default=None,
        description=(
            "The maximum number of iterations per time step for nonstationary "
            "computations. The computation moves to the next time step when this "
            "number is exceeded (SWAN default: `mxitns = 1`"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "NONSTATIONARY"
        if self.mxitns is not None:
            repr += f" mxitns={self.mxitns}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['nonstat', 'NONSTAT'] = Field(default='nonstat', description='Model type discriminator')

mxitns class-attribute instance-attribute 

mxitns: Optional[int] = Field(default=None, description='The maximum number of iterations per time step for nonstationary computations. The computation moves to the next time step when this number is exceeded (SWAN default: `mxitns = 1`')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
132
133
134
135
136
137
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "NONSTATIONARY"
    if self.mxitns is not None:
        repr += f" mxitns={self.mxitns}"
    return repr

STOPC

Bases: BaseSubComponent

Stopping criteria of Zijlema and Van der Westhuysen (2005).

.. code-block:: text

STOPC [dabs] [drel] [curvat] [npnts] ->STAT|NONSTAT [limiter]

With this option the user can influence the criterion for terminating the iterative procedure in the SWAN computations (both stationary and nonstationary). The criterion makes use of the second derivative, or curvature, of the iteration curve of the significant wave height. As the solution of a simulation approaches full convergence, the curvature of the iteration curve will tend to zero. SWAN stops the process if the relative change in Hs from one iteration to the next is less than drel and the curvature of the iteration curve of Hs normalized with Hs is less than curvat or the absolute change in Hs from one iteration to the next is less than dabs. Both conditions need to be fulfilled in more than fraction npnts percent of all wet grid points.

With respect to the QC modelling, another stopping criteria will be employed. Namely, SWAN stops the iteration process if the absolute change in Hs from one iterate to another is less than dabs * Hinc, where Hinc is the representative incident wave height, or the relative change in Hs from one to the next iteration is less than drel. These criteria must be fulfilled in more than npnts percent of all active, well-defined points.

References

  • Zijlema, M. and Van der Westhuysen, A. (2005). On convergence behaviour and numerical accuracy in stationary SWAN simulations of nearshore wind wave spectra, Coastal Engineering, 52(3), p. 337-256.

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import STOPC
stop = STOPC()
print(stop.render())
stop = STOPC(
    dabs=0.005,
    drel=0.01,
    curvat=0.005,
    npnts=99.5,
    mode=dict(model_type="nonstat", mxitns=1),
    limiter=0.1,
)
print(stop.render())
Source code in rompy_swan/subcomponents/numerics.py 
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
class STOPC(BaseSubComponent):
    """Stopping criteria of  Zijlema and Van der Westhuysen (2005).

    .. code-block:: text

        STOPC [dabs] [drel] [curvat] [npnts] ->STAT|NONSTAT [limiter]

    With this option the user can influence the criterion for terminating the iterative
    procedure in the SWAN computations (both stationary and nonstationary). The
    criterion makes use of the second derivative, or curvature, of the iteration curve
    of the significant wave height. As the solution of a simulation approaches full
    convergence, the curvature of the iteration curve will tend to zero. SWAN stops the
    process if the relative change in Hs from one iteration to the next is less than
    `drel` and the curvature of the iteration curve of Hs normalized with Hs is less
    than `curvat` or the absolute change in Hs from one iteration to the next is less
    than `dabs`. Both conditions need to be fulfilled in more than fraction `npnts`
    percent of all wet grid points.

    With respect to the QC modelling, another stopping criteria will be employed.
    Namely, SWAN stops the iteration process if the absolute change in Hs from one
    iterate to another is less than `dabs` * Hinc, where Hinc is the representative
    incident wave height, or the relative change in Hs from one to the next iteration
    is less than `drel`. These criteria must be fulfilled in more than `npnts`
    percent of all active, well-defined points.

    References
    ----------
    - Zijlema, M. and Van der Westhuysen, A. (2005). On convergence behaviour and
      numerical accuracy in stationary SWAN simulations of nearshore wind wave spectra,
      Coastal Engineering, 52(3), p. 337-256.

    Examples
    --------

    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import STOPC
        stop = STOPC()
        print(stop.render())
        stop = STOPC(
            dabs=0.005,
            drel=0.01,
            curvat=0.005,
            npnts=99.5,
            mode=dict(model_type="nonstat", mxitns=1),
            limiter=0.1,
        )
        print(stop.render())

    """

    model_type: Literal["stopc", "STOPC"] = Field(
        default="stopc", description="Model type discriminator"
    )
    dabs: Optional[float] = Field(
        default=None,
        description=(
            "Maximum absolute change in Hs from one iteration to the next "
            "(SWAN default: 0.005 [m] or 0.05 [-] in case of QC model)"
        ),
    )
    drel: Optional[float] = Field(
        default=None,
        description=(
            "Maximum relative change in Hs from one iteration to the next "
            "(SWAN default: 0.01 [-])"
        ),
    )
    curvat: Optional[float] = Field(
        default=None,
        description=(
            "Maximum curvature of the iteration curve of Hs normalised with Hs "
            "(SWAN default: 0.005 [-] (not used in the QC model))"
        ),
    )
    npnts: Optional[float] = Field(
        default=None,
        description=(
            "Percentage of points in the computational grid above which the stopping "
            "criteria needs to be satisfied (SWAN default: 99.5 [-])"
        ),
    )
    mode: Optional[Union[STAT, NONSTAT]] = Field(
        default=None,
        description="Termination criteria for stationary or nonstationary runs",
        discriminator="model_type",
    )
    limiter: Optional[float] = Field(
        default=None,
        description=(
            "Determines the maximum change per iteration of the energy density per "
            "spectral-bin given in terms of a fraction of the omni-directional "
            "Phillips level (SWAN default: 0.1)"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "STOPC"
        if self.dabs is not None:
            repr += f" dabs={self.dabs}"
        if self.drel is not None:
            repr += f" drel={self.drel}"
        if self.curvat is not None:
            repr += f" curvat={self.curvat}"
        if self.npnts is not None:
            repr += f" npnts={self.npnts}"
        if self.mode is not None:
            repr += f" {self.mode.render()}"
        if self.limiter is not None:
            repr += f" limiter={self.limiter}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['stopc', 'STOPC'] = Field(default='stopc', description='Model type discriminator')

dabs class-attribute instance-attribute 

dabs: Optional[float] = Field(default=None, description='Maximum absolute change in Hs from one iteration to the next (SWAN default: 0.005 [m] or 0.05 [-] in case of QC model)')

drel class-attribute instance-attribute 

drel: Optional[float] = Field(default=None, description='Maximum relative change in Hs from one iteration to the next (SWAN default: 0.01 [-])')

curvat class-attribute instance-attribute 

curvat: Optional[float] = Field(default=None, description='Maximum curvature of the iteration curve of Hs normalised with Hs (SWAN default: 0.005 [-] (not used in the QC model))')

npnts class-attribute instance-attribute 

npnts: Optional[float] = Field(default=None, description='Percentage of points in the computational grid above which the stopping criteria needs to be satisfied (SWAN default: 99.5 [-])')

mode class-attribute instance-attribute 

mode: Optional[Union[STAT, NONSTAT]] = Field(default=None, description='Termination criteria for stationary or nonstationary runs', discriminator='model_type')

limiter class-attribute instance-attribute 

limiter: Optional[float] = Field(default=None, description='Determines the maximum change per iteration of the energy density per spectral-bin given in terms of a fraction of the omni-directional Phillips level (SWAN default: 0.1)')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "STOPC"
    if self.dabs is not None:
        repr += f" dabs={self.dabs}"
    if self.drel is not None:
        repr += f" drel={self.drel}"
    if self.curvat is not None:
        repr += f" curvat={self.curvat}"
    if self.npnts is not None:
        repr += f" npnts={self.npnts}"
    if self.mode is not None:
        repr += f" {self.mode.render()}"
    if self.limiter is not None:
        repr += f" limiter={self.limiter}"
    return repr

ACCUR

Bases: BaseSubComponent

Stop the iterative procedure.

.. code-block:: text

ACCUR [drel] [dhoval] [dtoval] [npnts] ->STAT|NONSTAT [limiter]

With this option the user can influence the criterion for terminating the iterative procedure in the SWAN computations (both stationary and non-stationary modes). SWAN stops the iterations if (a), (b) and (c) are all satisfied:

a) The change in the local significant wave height Hs from one iteration to the next is less than (1) fraction drel of that height or (2) fraction dhoval of the average Hs over all grid points.

b) The change in the local mean wave period Tm01 from one iteration to the next is less than (1) fraction drel of that period or (2) fraction dtoval of the average mean wave period over all wet grid points.

c) Conditions (a) and (b) are fulfilled in more than fraction npnts% of all wet grid points.

Note

This command has become obsolete in SWAN 41.01. The command STOPC should be used.

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import ACCUR
accur = ACCUR()
print(accur.render())
accur = ACCUR(
    drel=0.01,
    dhoval=0.02,
    dtoval=0.02,
    npnts=98.0,
    mode=dict(model_type="nonstat", mxitns=1),
    limiter=0.1,
)
print(accur.render())
Source code in rompy_swan/subcomponents/numerics.py 
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
class ACCUR(BaseSubComponent):
    """Stop the iterative procedure.

    .. code-block:: text

        ACCUR [drel] [dhoval] [dtoval] [npnts] ->STAT|NONSTAT [limiter]

    With this option the user can influence the criterion for terminating the iterative
    procedure in the SWAN computations (both stationary and non-stationary modes).
    SWAN stops the iterations if (a), (b) and (c) are all satisfied:

    a) The change in the local significant wave height Hs from one iteration to the
       next is less than (1) fraction `drel` of that height or (2) fraction `dhoval`
       of the average Hs over all grid points.

    b) The change in the local mean wave period Tm01 from one iteration to the next is
       less than (1) fraction `drel` of that period or (2) fraction `dtoval` of the
       average mean wave period over all wet grid points.

    c) Conditions (a) and (b) are fulfilled in more than fraction `npnts%` of all wet
       grid points.

    Note
    ----
    This command has become obsolete in SWAN 41.01. The command STOPC should be used.

    Examples
    --------

    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import ACCUR
        accur = ACCUR()
        print(accur.render())
        accur = ACCUR(
            drel=0.01,
            dhoval=0.02,
            dtoval=0.02,
            npnts=98.0,
            mode=dict(model_type="nonstat", mxitns=1),
            limiter=0.1,
        )
        print(accur.render())

    """

    model_type: Literal["accur", "ACCUR"] = Field(
        default="accur", description="Model type discriminator"
    )
    drel: Optional[float] = Field(
        default=None,
        description=(
            "Maximum relative change in Hs or Tm01 from one iteration to the next "
            "(SWAN default: 0.02)"
        ),
    )
    dhoval: Optional[float] = Field(
        default=None,
        description=(
            "Fraction of the average Hs over all wet grid points below which the "
            "the stopping criteria needs to be satisfied (SWAN default: 0.02)"
        ),
    )
    dtoval: Optional[float] = Field(
        default=None,
        description=(
            "Fraction of the average Tm01 over all wet grid points below which the "
            "the stopping criteria needs to be satisfied (SWAN default: 0.02)"
        ),
    )
    npnts: Optional[float] = Field(
        default=None,
        description=(
            "Percentage of points in the computational grid above which the stopping "
            "criteria needs to be satisfied (SWAN default: 98)"
        ),
    )
    mode: Optional[Union[STAT, NONSTAT]] = Field(
        default=None,
        description="Termination criteria for stationary or nonstationary runs",
        discriminator="model_type",
    )
    limiter: Optional[float] = Field(
        default=None,
        description=(
            "Determines the maximum change per iteration of the energy density per "
            "spectral-bin given in terms of a fraction of the omni-directional "
            "Phillips level (SWAN default: 0.1)"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "ACCUR"
        if self.drel is not None:
            repr += f" drel={self.drel}"
        if self.dhoval is not None:
            repr += f" dhoval={self.dhoval}"
        if self.dtoval is not None:
            repr += f" dtoval={self.dtoval}"
        if self.npnts is not None:
            repr += f" npnts={self.npnts}"
        if self.mode is not None:
            repr += f" {self.mode.render()}"
        if self.limiter is not None:
            repr += f" limiter={self.limiter}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['accur', 'ACCUR'] = Field(default='accur', description='Model type discriminator')

drel class-attribute instance-attribute 

drel: Optional[float] = Field(default=None, description='Maximum relative change in Hs or Tm01 from one iteration to the next (SWAN default: 0.02)')

dhoval class-attribute instance-attribute 

dhoval: Optional[float] = Field(default=None, description='Fraction of the average Hs over all wet grid points below which the the stopping criteria needs to be satisfied (SWAN default: 0.02)')

dtoval class-attribute instance-attribute 

dtoval: Optional[float] = Field(default=None, description='Fraction of the average Tm01 over all wet grid points below which the the stopping criteria needs to be satisfied (SWAN default: 0.02)')

npnts class-attribute instance-attribute 

npnts: Optional[float] = Field(default=None, description='Percentage of points in the computational grid above which the stopping criteria needs to be satisfied (SWAN default: 98)')

mode class-attribute instance-attribute 

mode: Optional[Union[STAT, NONSTAT]] = Field(default=None, description='Termination criteria for stationary or nonstationary runs', discriminator='model_type')

limiter class-attribute instance-attribute 

limiter: Optional[float] = Field(default=None, description='Determines the maximum change per iteration of the energy density per spectral-bin given in terms of a fraction of the omni-directional Phillips level (SWAN default: 0.1)')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "ACCUR"
    if self.drel is not None:
        repr += f" drel={self.drel}"
    if self.dhoval is not None:
        repr += f" dhoval={self.dhoval}"
    if self.dtoval is not None:
        repr += f" dtoval={self.dtoval}"
    if self.npnts is not None:
        repr += f" npnts={self.npnts}"
    if self.mode is not None:
        repr += f" {self.mode.render()}"
    if self.limiter is not None:
        repr += f" limiter={self.limiter}"
    return repr

DIRIMPL

Bases: BaseSubComponent

Numerical scheme for refraction.

.. code-block:: text

DIRIMPL [cdd]

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import DIRIMPL
dirimpl = DIRIMPL()
print(dirimpl.render())
dirimpl = DIRIMPL(cdd=0.5)
print(dirimpl.render())
Source code in rompy_swan/subcomponents/numerics.py 
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
class DIRIMPL(BaseSubComponent):
    """Numerical scheme for refraction.

    .. code-block:: text

        DIRIMPL [cdd]

    Examples
    --------
    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import DIRIMPL
        dirimpl = DIRIMPL()
        print(dirimpl.render())
        dirimpl = DIRIMPL(cdd=0.5)
        print(dirimpl.render())

    """

    model_type: Literal["dirimpl", "DIRIMPL"] = Field(
        default="dirimpl", description="Model type discriminator"
    )
    cdd: Optional[float] = Field(
        default=None,
        description=(
            "A value of `cdd=0` corresponds to a central scheme and has the largest "
            "accuracy (diffusion ≈ 0) but the computation may more easily generate"
            "spurious fluctuations. A value of `cdd=1` corresponds to a first order"
            "upwind scheme and it is more diffusive and therefore preferable if "
            "(strong) gradients in depth or current are present (SWAN default: 0.5)"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "DIRIMPL"
        if self.cdd is not None:
            repr += f" cdd={self.cdd}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['dirimpl', 'DIRIMPL'] = Field(default='dirimpl', description='Model type discriminator')

cdd class-attribute instance-attribute 

cdd: Optional[float] = Field(default=None, description='A value of `cdd=0` corresponds to a central scheme and has the largest accuracy (diffusion ≈ 0) but the computation may more easily generatespurious fluctuations. A value of `cdd=1` corresponds to a first orderupwind scheme and it is more diffusive and therefore preferable if (strong) gradients in depth or current are present (SWAN default: 0.5)')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
399
400
401
402
403
404
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "DIRIMPL"
    if self.cdd is not None:
        repr += f" cdd={self.cdd}"
    return repr

SIGIMPL

Bases: BaseSubComponent

Frequency shifting accuracy.

.. code-block:: text

SIGIMpl [cfl] [eps2] [outp] [niter]

Controls the accuracy of computing the frequency shifting and the stopping criterion and amount of output for the SIP solver (used in the computations in the presence of currents or time varying depth)

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import SIGIMPL
sigimpl = SIGIMPL()
print(sigimpl.render())
sigimpl = SIGIMPL(css=0.5, eps2=1e-4, outp=0, niter=20)
print(sigimpl.render())
Source code in rompy_swan/subcomponents/numerics.py 
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
class SIGIMPL(BaseSubComponent):
    """Frequency shifting accuracy.

    .. code-block:: text

        SIGIMpl [cfl] [eps2] [outp] [niter]

    Controls the accuracy of computing the frequency shifting and the stopping
    criterion and amount of output for the SIP solver (used in the computations in the
    presence of currents or time varying depth)

    Examples
    --------
    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import SIGIMPL
        sigimpl = SIGIMPL()
        print(sigimpl.render())
        sigimpl = SIGIMPL(css=0.5, eps2=1e-4, outp=0, niter=20)
        print(sigimpl.render())

    """

    model_type: Literal["sigimpl", "SIGIMPL"] = Field(
        default="sigimpl", description="Model type discriminator"
    )
    css: Optional[float] = Field(
        default=None,
        description=(
            "A value of `css=0` corresponds to a central scheme and has the largest "
            "accuracy (diffusion ≈ 0) but the computation may more easily generate "
            "spurious fluctuations. A value of `css=1` corresponds to a first order "
            "upwind scheme and it is more diffusive and therefore preferable if "
            "(strong) gradients in depth or current are present (SWAN default: 0.5)"
        ),
    )
    eps2: Optional[float] = Field(
        default=None,
        description=(
            "Relative stopping criterion to terminate the linear solver (SIP or SOR). "
            "(SWAN default: 1.e-4 in case of SIP and 1.e-6 in case of SOR)"
        ),
    )
    outp: Optional[Literal[0, 1, 2, 3]] = Field(
        default=None,
        description=(
            "Output for the iterative solver:\n\n* 0 = no output\n* 1 = additional "
            "information about the iteration process is written to the PRINT file "
            "\n* 2 = gives a maximal amount of output concerning the iteration "
            "process\n* 3 = summary of the iteration process\n\n(SWAN default: 0)"
        ),
    )
    niter: Optional[int] = Field(
        default=None,
        description=(
            "Maximum number of iterations for the linear solver (SWAN default: 20 in "
            "case of SIP and 1000 in case of SOR)"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "SIGIMPL"
        if self.css is not None:
            repr += f" css={self.css}"
        if self.eps2 is not None:
            repr += f" eps2={self.eps2}"
        if self.outp is not None:
            repr += f" outp={self.outp}"
        if self.niter is not None:
            repr += f" niter={self.niter}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['sigimpl', 'SIGIMPL'] = Field(default='sigimpl', description='Model type discriminator')

css class-attribute instance-attribute 

css: Optional[float] = Field(default=None, description='A value of `css=0` corresponds to a central scheme and has the largest accuracy (diffusion ≈ 0) but the computation may more easily generate spurious fluctuations. A value of `css=1` corresponds to a first order upwind scheme and it is more diffusive and therefore preferable if (strong) gradients in depth or current are present (SWAN default: 0.5)')

eps2 class-attribute instance-attribute 

eps2: Optional[float] = Field(default=None, description='Relative stopping criterion to terminate the linear solver (SIP or SOR). (SWAN default: 1.e-4 in case of SIP and 1.e-6 in case of SOR)')

outp class-attribute instance-attribute 

outp: Optional[Literal[0, 1, 2, 3]] = Field(default=None, description='Output for the iterative solver:\n\n* 0 = no output\n* 1 = additional information about the iteration process is written to the PRINT file \n* 2 = gives a maximal amount of output concerning the iteration process\n* 3 = summary of the iteration process\n\n(SWAN default: 0)')

niter class-attribute instance-attribute 

niter: Optional[int] = Field(default=None, description='Maximum number of iterations for the linear solver (SWAN default: 20 in case of SIP and 1000 in case of SOR)')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
468
469
470
471
472
473
474
475
476
477
478
479
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "SIGIMPL"
    if self.css is not None:
        repr += f" css={self.css}"
    if self.eps2 is not None:
        repr += f" eps2={self.eps2}"
    if self.outp is not None:
        repr += f" outp={self.outp}"
    if self.niter is not None:
        repr += f" niter={self.niter}"
    return repr

CTHETA

Bases: BaseSubComponent

Prevents excessive directional turning.

.. code-block:: text

CTheta [cfl]

This option prevents an excessive directional turning at a single grid point or vertex due to a very coarse bathymetry or current locally. This option limits the directional turning rate cθ based on the CFL restriction. (See Eq. 3.41 of Scientific/Technical documentation). See also the final remark in Section 2.6.3. Note that if this command is not specified, then the limiter is not activated.

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import CTHETA
ctheta = CTHETA()
print(ctheta.render())
ctheta = CTHETA(cfl=0.9)
print(ctheta.render())
Source code in rompy_swan/subcomponents/numerics.py 
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
class CTHETA(BaseSubComponent):
    """Prevents excessive directional turning.

    .. code-block:: text

        CTheta [cfl]

    This option prevents an excessive directional turning at a single grid point or
    vertex due to a very coarse bathymetry or current locally. This option limits the
    directional turning rate cθ based on the CFL restriction. (See Eq. 3.41 of
    Scientific/Technical documentation). See also the final remark in Section 2.6.3.
    Note that if this command is not specified, then the limiter is not activated.

    Examples
    --------
    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import CTHETA
        ctheta = CTHETA()
        print(ctheta.render())
        ctheta = CTHETA(cfl=0.9)
        print(ctheta.render())

    """

    model_type: Literal["ctheta", "CTHETA"] = Field(
        default="ctheta", description="Model type discriminator"
    )
    cfl: Optional[float] = Field(
        default=None,
        description=(
            "Upper limit for the CFL restriction for ctheta. A suggestion for this "
            "parameter is `cfl = 0.9` (SWAN default: 0.9 when CTHETA is activated)"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "CTHETA"
        if self.cfl is not None:
            repr += f" cfl={self.cfl}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['ctheta', 'CTHETA'] = Field(default='ctheta', description='Model type discriminator')

cfl class-attribute instance-attribute 

cfl: Optional[float] = Field(default=None, description='Upper limit for the CFL restriction for ctheta. A suggestion for this parameter is `cfl = 0.9` (SWAN default: 0.9 when CTHETA is activated)')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
519
520
521
522
523
524
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "CTHETA"
    if self.cfl is not None:
        repr += f" cfl={self.cfl}"
    return repr

CSIGMA

Bases: BaseSubComponent

Prevents excessive directional turning.

.. code-block:: text

CSigma [cfl]

This option prevents an excessive frequency shifting at a single grid point or vertex due to a very coarse bathymetry or current locally. This option limits the frequency shifting rate csigma based on the CFL restriction. See also the final remark in Section 2.6.3. Note that if this command is not specified, then the limiter is not activated.

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import CSIGMA
csigma = CSIGMA()
print(csigma.render())
csigma = CSIGMA(cfl=0.9)
print(csigma.render())
Source code in rompy_swan/subcomponents/numerics.py 
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
class CSIGMA(BaseSubComponent):
    """Prevents excessive directional turning.

    .. code-block:: text

        CSigma [cfl]

    This option prevents an excessive frequency shifting at a single grid point or
    vertex due to a very coarse bathymetry or current locally. This option limits the
    frequency shifting rate csigma based on the CFL restriction. See also the final
    remark in Section 2.6.3. Note that if this command is not specified, then the
    limiter is not activated.

    Examples
    --------
    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import CSIGMA
        csigma = CSIGMA()
        print(csigma.render())
        csigma = CSIGMA(cfl=0.9)
        print(csigma.render())

    """

    model_type: Literal["ctheta", "CTHETA"] = Field(
        default="ctheta", description="Model type discriminator"
    )
    cfl: Optional[float] = Field(
        default=None,
        description=(
            "Upper limit for the CFL restriction for csigma. A suggestion for this "
            "parameter is `cfl = 0.9` (SWAN default: 0.9 when CSIGMA is activated)"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "CSIGMA"
        if self.cfl is not None:
            repr += f" cfl={self.cfl}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['ctheta', 'CTHETA'] = Field(default='ctheta', description='Model type discriminator')

cfl class-attribute instance-attribute 

cfl: Optional[float] = Field(default=None, description='Upper limit for the CFL restriction for csigma. A suggestion for this parameter is `cfl = 0.9` (SWAN default: 0.9 when CSIGMA is activated)')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
564
565
566
567
568
569
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "CSIGMA"
    if self.cfl is not None:
        repr += f" cfl={self.cfl}"
    return repr

SETUP

Bases: BaseSubComponent

Stop criteria in the computation of wave setup.

.. code-block:: text

SETUP [eps2] [outp] [niter]

Controls the stopping criterion and amount of output for the SOR solver in the computation of the wave-induced set-up.

Examples

.. ipython:: python :okwarning:

from rompy_swan.subcomponents.numerics import SETUP
setup = SETUP()
print(setup.render())
setup = SETUP(eps2=1e-4, outp=0, niter=20)
print(setup.render())
Source code in rompy_swan/subcomponents/numerics.py 
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
class SETUP(BaseSubComponent):
    """Stop criteria in the computation of wave setup.

    .. code-block:: text

        SETUP [eps2] [outp] [niter]

    Controls the stopping criterion and amount of output for the SOR solver in the
    computation of the wave-induced set-up.

    Examples
    --------
    .. ipython:: python
        :okwarning:

        from rompy_swan.subcomponents.numerics import SETUP
        setup = SETUP()
        print(setup.render())
        setup = SETUP(eps2=1e-4, outp=0, niter=20)
        print(setup.render())

    """

    model_type: Literal["setup", "SETUP"] = Field(
        default="setup", description="Model type discriminator"
    )
    eps2: Optional[float] = Field(
        default=None,
        description=(
            "Relative stopping criterion to terminate the linear solver (SIP or SOR). "
            "(SWAN default: 1.e-4 in case of SIP and 1.e-6 in case of SOR)"
        ),
    )
    outp: Optional[Literal[0, 1, 2, 3]] = Field(
        default=None,
        description=(
            "Output for the iterative solver:\n\n* 0 = no output\n* 1 = additional "
            "information about the iteration process is written to the PRINT file "
            "\n* 2 = gives a maximal amount of output concerning the iteration process "
            "\n* 3 = summary of the iteration process\n\n(SWAN default: 0)"
        ),
    )
    niter: Optional[int] = Field(
        default=None,
        description=(
            "Maximum number of iterations for the linear solver (SWAN default: 20 in "
            "case of SIP and 1000 in case of SOR)"
        ),
    )

    def cmd(self) -> str:
        """Command file string for this component."""
        repr = "SETUP"
        if self.eps2 is not None:
            repr += f" eps2={self.eps2}"
        if self.outp is not None:
            repr += f" outp={self.outp}"
        if self.niter is not None:
            repr += f" niter={self.niter}"
        return repr

Attributes

model_type class-attribute instance-attribute 

model_type: Literal['setup', 'SETUP'] = Field(default='setup', description='Model type discriminator')

eps2 class-attribute instance-attribute 

eps2: Optional[float] = Field(default=None, description='Relative stopping criterion to terminate the linear solver (SIP or SOR). (SWAN default: 1.e-4 in case of SIP and 1.e-6 in case of SOR)')

outp class-attribute instance-attribute 

outp: Optional[Literal[0, 1, 2, 3]] = Field(default=None, description='Output for the iterative solver:\n\n* 0 = no output\n* 1 = additional information about the iteration process is written to the PRINT file \n* 2 = gives a maximal amount of output concerning the iteration process \n* 3 = summary of the iteration process\n\n(SWAN default: 0)')

niter class-attribute instance-attribute 

niter: Optional[int] = Field(default=None, description='Maximum number of iterations for the linear solver (SWAN default: 20 in case of SIP and 1000 in case of SOR)')

Functions

cmd 

cmd() -> str

Command file string for this component.

Source code in rompy_swan/subcomponents/numerics.py 
622
623
624
625
626
627
628
629
630
631
def cmd(self) -> str:
    """Command file string for this component."""
    repr = "SETUP"
    if self.eps2 is not None:
        repr += f" eps2={self.eps2}"
    if self.outp is not None:
        repr += f" outp={self.outp}"
    if self.niter is not None:
        repr += f" niter={self.niter}"
    return repr