diff --git a/control/modelsimp.py b/control/modelsimp.py index 06c3d350d..e12fb4fa2 100644 --- a/control/modelsimp.py +++ b/control/modelsimp.py @@ -49,7 +49,9 @@ from .statesp import StateSpace from .statefbk import gram -__all__ = ['hsvd', 'balred', 'modred', 'era', 'markov', 'minreal'] +__all__ = ['hankel_singular_values', 'balanced_reduction', 'model_reduction', + 'minimal_realization', 'eigensys_realization', 'markov', 'hsvd', + 'balred', 'modred', 'minreal', 'era'] # Hankel Singular Value Decomposition @@ -57,7 +59,7 @@ # The following returns the Hankel singular values, which are singular values # of the matrix formed by multiplying the controllability and observability # Gramians -def hsvd(sys): +def hankel_singular_values(sys): """Calculate the Hankel singular values. Parameters @@ -106,7 +108,7 @@ def hsvd(sys): return hsv[::-1] -def modred(sys, ELIM, method='matchdc'): +def model_reduction(sys, ELIM, method='matchdc'): """ Model reduction of `sys` by eliminating the states in `ELIM` using a given method. @@ -216,7 +218,7 @@ def modred(sys, ELIM, method='matchdc'): return rsys -def balred(sys, orders, method='truncate', alpha=None): +def balanced_reduction(sys, orders, method='truncate', alpha=None): """Balanced reduced order model of sys of a given order. States are eliminated based on Hankel singular value. If sys has unstable modes, they are removed, the @@ -340,7 +342,7 @@ def balred(sys, orders, method='truncate', alpha=None): return rsys -def minreal(sys, tol=None, verbose=True): +def minimal_realization(sys, tol=None, verbose=True): ''' Eliminates uncontrollable or unobservable states in state-space models or cancelling pole-zero pairs in transfer functions. The @@ -368,7 +370,7 @@ def minreal(sys, tol=None, verbose=True): return sysr -def era(YY, m, n, nin, nout, r): +def eigensys_realization(YY, m, n, nin, nout, r): """Calculate an ERA model of order `r` based on the impulse-response data `YY`. @@ -556,3 +558,10 @@ def markov(Y, U, m=None, transpose=False): # Return the first m Markov parameters return H if transpose else np.transpose(H) + +# Function aliases +hsvd = hankel_singular_values +balred = balanced_reduction +modred = model_reduction +minreal = minimal_realization +era = eigensys_realization diff --git a/doc/control.rst b/doc/control.rst index efd643d8a..366454d42 100644 --- a/doc/control.rst +++ b/doc/control.rst @@ -133,11 +133,11 @@ Model simplification tools .. autosummary:: :toctree: generated/ - minreal - balred - hsvd - modred - era + minimal_realization + balanced_reduction + hankel_singular_values + model_reduction + eigensys_realization markov Nonlinear system support