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WV_FN_SYMLET

Syntax | Return Value | Arguments | Keywords | Version History | See Also

The WV_FN_SYMLET function constructs wavelet coefficients for the Symlet wavelet function.


Note
The Symlet wavelet for orders 1–3 are the same as the Daubechies wavelets of the same order.

Syntax

Result = WV_FN_SYMLET( [Order, Scaling, Wavelet, Ioff, Joff] )

Return Value

The returned value of this function is an anonymous structure of information about the particular wavelet.

Table 4-12: Structure Tags for Result 

Table 4-12: Structure Tags for Result 
Tag
Type
Definition
FAMILY
STRING
`Symlet'
ORDER_NAME
STRING
`Order'
ORDER_RANGE
INTARR(3)
[1, 15, 4] Valid order range [first, last, default]
ORDER
INT
The chosen Order
DISCRETE
INT
1 [0=continuous, 1=discrete]
ORTHOGONAL
INT
1 [0=nonorthogonal, 1=orthogonal]
SYMMETRIC
INT
2 [0=asymmetric, 1=symm., 2=near symm.]
SUPPORT
INT
2*Order – 1 [Compact support width]
MOMENTS
INT
Order [Number of vanishing moments]
REGULARITY
DOUBLE
The number of continuous derivatives

Arguments

Order

A scalar that specifies the order number for the wavelet. The default is 4.

Scaling

On output, contains a vector of double-precision scaling (father) coefficients.

Wavelet

On output, contains a vector of double-precision wavelet (mother) coefficients.

Ioff

On output, contains an integer that specifies the support offset for Scaling.

Joff

On output, contains an integer that specifies the support offset for Wavelet.


Note
If none of the above arguments are present then the function will simply return the Result structure using the default Order.

Keywords

None.

Reference

Coefficients for orders 1–10 are from Daubechies, I., 1992: Ten Lectures on Wavelets, SIAM, p. 198. Note that Daubechies has multiplied by Sqrt(2), and for some orders the coefficients are reversed. Coefficients for orders 11–15 are from http://www.isds.duke.edu/~brani/filters.html.

Version History

5.3
Introduced

See Also

WV_DWT, WV_FN_COIFLET, WV_FN_DAUBECHIES, WV_FN_HAAR

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