pycif.plugins.obsoperators.random — API reference

Configuration reference: random plugin

pycif.plugins.obsoperators.random.obsoper.obsoper(self, controlvect, obsvect, mode, run_id=0, datei=datetime.datetime(1979, 1, 1, 0, 0), datef=datetime.datetime(2100, 1, 1, 0, 0), workdir='./', reload_results=False, check_transforms=False, ignore_exceptions=False, force_fetch_results=False, **kwargs)

Apply the random observation operator in forward, tangent-linear or adjoint mode.

Implements a simple matrix–vector product using the random matrix self.H_matrix built by ini_data(). Because no physical model is involved, the operator is instantaneous and exact in all three modes.

Forward (mode='fwd'):

\[\mathbf{y}_\text{sim} = \mathbf{H}\,\mathbf{x}\]

Sets obsvect.ysim and returns obsvect.

Tangent-linear (mode='tl'):

\[\mathbf{y}_\text{sim} = \mathbf{H}\,\mathbf{x}, \qquad \delta\mathbf{y} = \mathbf{H}\,\delta\mathbf{x}\]

Sets both obsvect.ysim and obsvect.dy; returns obsvect.

Adjoint (mode='adj'):

\[\delta\mathbf{x} = \mathbf{H}^\top\,\delta\mathbf{y}\]

Sets controlvect.dx; returns controlvect.

Args:

self (ObsOperator): plugin instance; must have H_matrix set by a

prior call to ini_data().

controlvect (ControlVect): control-vector object. controlvect.x

is read in fwd / tl modes; controlvect.dx is read in tl mode and written in adj mode.

obsvect (ObsVect): observation-vector object. obsvect.ysim is

written in fwd / tl modes; obsvect.dy is read in adj mode and written in tl mode.

mode (str): execution mode — one of 'fwd', 'tl', or 'adj'. run_id (int, optional): run identifier (unused; present for interface

compatibility). Defaults to 0.

datei (datetime.datetime, optional): simulation start date (unused;

present for interface compatibility). Defaults to datetime.datetime(1979, 1, 1).

datef (datetime.datetime, optional): simulation end date (unused;

present for interface compatibility). Defaults to datetime.datetime(2100, 1, 1).

workdir (str, optional): working directory (unused; present for

interface compatibility). Defaults to "./"

reload_results (bool, optional): reload pre-computed results (unused).

Defaults to False.

check_transforms (bool, optional): validate transform consistency

(unused). Defaults to False.

ignore_exceptions (bool, optional): swallow non-fatal errors (unused).

Defaults to False.

force_fetch_results (bool, optional): if True, raise

IOError immediately to signal that results must be fetched from a previous run rather than recomputed. Defaults to False.

from ….utils.check.errclass import CifIOError

**kwargs: additional keyword arguments (ignored).

Returns:

ObsVect: in 'fwd' and 'tl' modes — the updated obsvect.

ControlVect: in 'adj' mode — the updated controlvect.

Raises:

IOError: if force_fetch_results is True.