 TriangleWindow - Maple Help

SignalProcessing

 TriangleWindow
 multiply an array of samples by a triangular windowing function Calling Sequence TriangleWindow(A) Parameters

 A - Array of real or complex numeric values; the signal Options

 • container : Array, predefined Array for holding results
 • inplace : truefalse, specifies that output should overwrite input Description

 • The TriangleWindow(A) command multiplies the Array A by the triangular windowing function and returns the result in an Array having the same length.
 • The triangular windowing function $w\left(k\right)$ is defined as follows for a sample with $N$ points.

$w\left(k\right)=\left\{\begin{array}{cc}\frac{k}{m}& 1\le k\le m\\ w\left(N-k-1\right)& m

 • where $m=\frac{N}{2}$ for even $N$, and $m=\frac{N}{2}-\frac{1}{2}$ for odd $N$.
 • Before the code performing the computation runs, A is converted to datatype float or complex if it does not have one of those datatypes already. For this reason, it is most efficient if A has one of these datatypes beforehand. This does not apply if inplace is true.
 • If the container=C option is provided, then the results are put into C and C is returned. With this option, no additional memory is allocated to store the result. The container must be an Array of the same size and datatype as A.
 • If the inplace or inplace=true option is provided, then A is overwritten with the results. In this case, the container option is ignored. • The SignalProcessing[TriangleWindow] command is thread-safe as of Maple 18. Examples

 > $\mathrm{with}\left(\mathrm{SignalProcessing}\right):$
 > $N≔1024$
 ${N}{≔}{1024}$ (1)
 > $\mathrm{s1}≔\mathrm{TriangleWindow}\left(\mathrm{Array}\left(1..N,\mathrm{fill}=1\right)\right)$ > $\mathrm{dataplot}\left(\mathrm{s1},\mathrm{style}=\mathrm{line}\right)$ > $\mathrm{s2}≔\mathrm{TriangleWindow}\left(\mathrm{Array}\left(1..N,i→\mathrm{sin}\left(i\cdot 0.1\right)\right)\right)$ > $\mathrm{dataplot}\left(\mathrm{s2},\mathrm{style}=\mathrm{line}\right)$  Compatibility

 • The SignalProcessing[TriangleWindow] command was introduced in Maple 18.