numpy.polynomial.chebyshev.chebsub — NumPy v1.11 Manual (original) (raw)
numpy.polynomial.chebyshev.chebsub(c1, c2)[source]¶
Subtract one Chebyshev series from another.
Returns the difference of two Chebyshev series c1 - c2. The sequences of coefficients are from lowest order term to highest, i.e., [1,2,3] represents the series T_0 + 2*T_1 + 3*T_2.
| Parameters: | c1, c2 : array_like 1-D arrays of Chebyshev series coefficients ordered from low to high. |
|---|---|
| Returns: | out : ndarray Of Chebyshev series coefficients representing their difference. |
Notes
Unlike multiplication, division, etc., the difference of two Chebyshev series is a Chebyshev series (without having to “reproject” the result onto the basis set) so subtraction, just like that of “standard” polynomials, is simply “component-wise.”
Examples
from numpy.polynomial import chebyshev as C c1 = (1,2,3) c2 = (3,2,1) C.chebsub(c1,c2) array([-2., 0., 2.]) C.chebsub(c2,c1) # -C.chebsub(c1,c2) array([ 2., 0., -2.])