getpacket.wp(wavethresh)
getpacket.wp()所属R语言包：wavethresh
Get packet of coefficients from a wavelet packet object (wp).
包系数小波包的对象（WP）。
译者：生物统计家园网 机器人LoveR
描述----------Description----------
This function extracts and returns a packet of coefficients from a wavelet packet (wp) object.
此功能提取物和返回数据包的小波包系数（wp）对象。
用法----------Usage----------
## S3 method for class 'wp':
getpacket(wp, level, index, ... )
参数----------Arguments----------
参数：wp
Wavelet packet object from which you wish to extract the packet from.
小波包对象，从中你要提取的数据包。
参数：level
The resolution level of the coefficients that you wish to extract.
分辨率级别的系数要提取。
参数：index
The index number within the resolution level of the packet of coefficients that you wish to extract.
该指数在分辨率级别的数据包要提取的系数。
参数：...
any other arguments
任何其他参数
Details
详细信息----------Details----------
The wp produces a wavelet packet object. The coefficients in this structure can be organised into a binary tree with each node in the tree containing a packet of coefficients.
wp产生一个小波包对象。在树中，每个节点包含一个数据包的系数，在该结构中的系数可以被组织成一个二进制树。
Each packet of coefficients is obtained by chaining together the effect of the two packet operators DG and DH: these are the high and low pass quadrature mirror filters of the Mallat pyramid algorithm scheme followed by decimation (see Mallat~(1989b)).
的系数是通过以下方式获得的每个数据包连接起来的两个数据包的运营商DG和DH的影响：这些是高通和低通正交镜像滤波器的Mallat金字塔算法计划者抽取（见Mallat的~（1989年b））。
Starting with data c^J at resolution level J containing 2^J data points the wavelet packet algorithm operates as follows. First DG and DH are applied to c^J producing d^{J-1} and c^{J-1} respectively. Each of these sets of coefficients is of length one half of the original data: i.e. 2^{J-1}. Each of these sets of coefficients is a set of wavelet packet coefficients. The algorithm then applies both DG and DH to both d^{J-1} and c^{J-1} to form a four sets of coefficients at level J-2. Both operators are used again on the four sets to produce 8 sets, then again on the 8 sets to form 16 sets and so on. At level j=J,...,0 there are 2^{J-j} packets of coefficients each containing 2^j coefficients.
从数据c^J分辨率为J级的2^J数据点的小波包算法的工作过程如下。第一DG和DHc^J生产d^{J-1}和c^{J-1}分别。的系数的每一个，这些套的长度为一半的原始数据：即2^{J-1}。这些系数集是一组的小波包系数。然后，该算法既适用于DG和DH都d^{J-1}和c^{J-1}，形成四套系数在J-2级。这两个运营商的四套上再次使用，以产生8组，然后再上的8套以形成16套等。在级j = J，...，0，有2^{J-j}的系数的数据包的各含2^j系数。
This function enables whole packets of coefficients to be extracted at any resolution level. The index argument chooses a particular packet within each level and thus ranges from 0 (which always refer to the father wavelet coefficients), 1 (which always refer to the mother wavelet coefficients) up to 2^{J-j}.
此功能使整个报文中提取系数，以在任何分辨率级别。 index参数在每个级别中选择一个特定的数据包，范围从0（通常是指父亲的小波系数），1（通常是指母小波系数）2^{J-j}。
值----------Value----------
A vector containing the packet of wavelet packet coefficients that you wished to extract.
一个向量，包含数据包，你希望提取的小波包系数。
RELEASE----------RELEASE----------
Version 3.9 Copyright Guy Nason 1998
版本3.9版权所有1998年盖利晨
（作者）----------Author(s)----------
G P Nason
参见----------See Also----------
wp, putpacket.wp, basisplot.wp, draw.wp, InvBasis.wp, MaNoVe.wp, nlevels.wp, plot.wp. threshold.wp.
wp，putpacket.wp，basisplot.wp，draw.wp，InvBasis.wp，MaNoVe.wp，nlevels.wp，plot.wp。 threshold.wp。
实例----------Examples----------
#[]
# Take the wavelet packet transform of some random data[以小波包变换的一些随机数据]
#[]
MyWP <- wp(rnorm(1:512))
#[]
# The above data set was 2^9 in length. Therefore there are[上面的数据集是2 ^ 9的长度。因此有]
# coefficients at resolution levels 0, 1, 2, ..., and 8.[分辨率级别0，1，2，...，和8的系数。]
#[]
# The high resolution coefficients are at level 8.[高分辨率的系数是在8级。]
# There should be 256 DG coefficients and 256 DH coefficients[应该有256 DG系数和256 DH系数]
#[]
length(getpacket(MyWP, level=8, index=0))
#[1] 256[[1] 256]
length(getpacket(MyWP, level=8, index=1))
#[1] 256[[1] 256]
#[]
# The next command shows that there are only two packets at level 8[下一个命令显示，有两包8级]
#[]
## Not run: getpacket(MyWP, level=8, index=2)[＃不运行：getpacket（MyWP，水平= 8，指数= 2）]
#Index was too high, maximum for this level is 1 [指数过高，最大为这个级别是1]
#Error in getpacket.wp(MyWP, level = 8, index = 2): Error occured[错误在getpacket.wp（级别= 8，指数= 2 MyWP，）：发生错误]
#Dumped[甩]
#[]
# There should be 4 coefficients at resolution level 2[应该有4个系数的分辨率为2级]
#[]
# The father wavelet coefficients are (index=0)[父亲的小波系数（指数= 0）]
getpacket(MyWP, level=2, index=0)
#[1] -0.9736576 0.5579501 0.3100629 -0.3834068[[1] -0.9736576 0.5579501 0.3100629 -0.3834068]
#[]
# The mother wavelet coefficients are (index=1)[母小波系数（指数）=（1）]
#[]
#[1] 0.72871405 0.04356728 -0.43175307 1.77291483[[1] 0.72871405 0.04356728 -0.43175307 1.77291483]
#[]
# There will be 127 packets at this level.[在这个级别将有127包。]
#[]
转载请注明:出自 生物统计家园网(http://www.biostatistic.net)。
注：
注1：为了方便大家学习，本文档为生物统计家园网机器人LoveR翻译而成，仅供个人R语言学习参考使用，生物统计家园保留版权。
注2：由于是机器人自动翻译，难免有不准确之处，使用时仔细对照中、英文内容进行反复理解，可以帮助R语言的学习。
注3：如遇到不准确之处，请在本贴的后面进行回帖，我们会逐渐进行修订。
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发表于 2012-10-1 17:20:28
