lsst.afw g9029821c7d+231b49cb4f
_chebyshevBoundedField.py
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21
22import numpy as np
23
24from lsst.utils import continueClass
25from ._math import ChebyshevBoundedField, ChebyshevBoundedFieldControl
26
27__all__ = [] # import this module only for its side effects
28
29
30@continueClass
31class ChebyshevBoundedField: # noqa: F811
32 @classmethod
33 def approximate(cls, boundedField,
34 orderX=3, orderY=3,
35 nStepX=100, nStepY=100):
36 """
37 Approximate a bounded field as a ChebyshevBoundedField.
38
39 Parameters
40 ----------
41 boundedField : `lsst.afw.math.BoundedField`
42 A bounded field to approximate
43 orderX : `int`, optional
44 Order of the Chebyshev polynomial in the x direction.
45 Default is 3.
46 orderY : `int`, optional
47 Order of the Chebyshev polynomial in the y direction.
48 Default is 3.
49 nStepX : `int`, optional
50 Number of x steps to approximate boundedField.
51 Default is 100.
52 nStepY : `int`, optional
53 Number of y steps to approximate boundedField.
54 Default is 100.
55
56 Returns
57 -------
58 chebyshevBoundedField : `lsst.afw.math.ChebyshevBoundedField`
59 """
60
61 ctrl = ChebyshevBoundedFieldControl()
62 ctrl.orderX = orderX
63 ctrl.orderY = orderY
64 ctrl.triangular = False
65
66 bbox = boundedField.getBBox()
67
68 xSteps = np.linspace(bbox.getMinX(), bbox.getMaxX(), nStepX)
69 ySteps = np.linspace(bbox.getMinY(), bbox.getMaxY(), nStepY)
70
71 x = np.tile(xSteps, nStepY)
72 y = np.repeat(ySteps, nStepX)
73
74 return cls.fit(bbox, x, y, boundedField.evaluate(x, y), ctrl)
def approximate(cls, boundedField, orderX=3, orderY=3, nStepX=100, nStepY=100)
An abstract base class for 2-d functions defined on an integer bounding boxes.
Definition: BoundedField.h:55
A BoundedField based on 2-d Chebyshev polynomials of the first kind.