找回密码
 注册
查看: 3502|回复: 0

R语言 xcms包 findPeaks.centWave-methods()函数中文帮助文档(中英文对照)

[复制链接]
发表于 2012-2-26 16:05:10 | 显示全部楼层 |阅读模式
findPeaks.centWave-methods(xcms)
findPeaks.centWave-methods()所属R语言包:xcms

                                        Feature detection for high resolution LC/MS data
                                         高分辨率LC / MS数据的功能检测

                                         译者:生物统计家园网 机器人LoveR

描述----------Description----------

Peak density and wavelet based feature detection for high resolution LC/MS data in centroid mode
峰值电流密度和高分辨率的LC / MS数据的质心模式基于小波特征检测


参数----------Arguments----------

参数:object
xcmsSet object
xcmsSet对象


参数:ppm
maxmial tolerated m/z deviation in consecutive scans, in ppm (parts per million)
maxmial容忍的m / z偏差在连续扫描,以ppm(百万分之一)


参数:peakwidth
Chromatographic peak width, given as range (min,max) in seconds
色谱峰宽,范围(最小值,最大值)在几秒钟内


参数:snthresh
signal to noise ratio cutoff, definition see below.
信号噪声比截止,定义见下文。


参数:prefilter
prefilter=c(k,I). Prefilter step for the first phase. Mass traces are only retained if they contain at least k peaks with intensity >= I.
prefilter=c(k,I)。第一阶段为预过滤步骤。大规模的痕迹只保留如果它们包含至少k峰强度> =I。


参数:mzCenterFun
Function to calculate the m/z center of the feature: wMean intensity weighted mean of the feature m/z values, mean mean of the feature m/z values, apex use m/z value at peak apex,  wMeanApex3 intensity weighted mean of the m/z value at peak apex and the m/z value left and right of it, meanApex3 mean of the m/z value at peak apex and the m/z value left and right of it.  
函数来计算的m / z为中心的功能:wMean强度特征m / z值的加权平均,meanm / z值的功能意味着,apex使用M / z值,在峰顶wMeanApex3强度在峰顶的m / z值的m / z值的左,右,加权平均,meanApex3m / z值意味着在峰顶和m / z值的左和它的权利。


参数:integrate
Integration method. If =1 peak limits are found through descent on the mexican hat filtered data, if =2 the descent is done on the real data. Method 2 is very accurate but prone to noise, while method 1 is more robust to noise but less exact.  
集成方法。如果=1峰值限制被发现筛选后的数据通过血统的墨西哥帽,如果=2血统是做真实的数据。方法2是非常准确,但容易产生噪音,而方法1是更强大的噪音,但不太准确。


参数:mzdiff
minimum difference in m/z for peaks with overlapping retention times, can be negative to allow overlap  
最小的m / z差异峰重叠的保留时间,可以是负的,允许重叠


参数:fitgauss
logical, if TRUE a Gaussian is fitted to each peak  
逻辑,如果真高斯拟合每个峰


参数:scanrange
scan range to process
扫描范围内处理


参数:noise
optional argument which is useful for data that was centroided without any intensity threshold, centroids with intensity < noise are omitted from ROI detection
可选参数,这是非常有用的数据centroided没有任何强度阈值,强度<重心noise省略的投资回报率检测


参数:sleep
number of seconds to pause between plotting peak finding cycles  
暂停之间绘制峰寻找周期秒数


参数:verbose.columns
logical, if TRUE additional peak meta data columns are returned   
逻辑,如果真正的额外峰元数据列返回


Details

详情----------Details----------

This algorithm is most suitable for high resolution LC/{TOF,OrbiTrap,FTICR}-MS data in centroid mode. In the first phase of the method mass traces (characterised as regions with less than ppm m/z deviation in consecutive scans) in the LC/MS map are located. In the second phase these mass traces are further analysed.  Continuous wavelet transform (CWT) is used to locate chromatographic peaks on different scales.
这种算法是最适合高分辨率的LC / {飞行时间,的Orbitrap,FTICR}-MS数据的质心模式。在第一阶段的方法大规模的痕迹在LC / MS的图(比ppmm / z为连续扫描的偏差以内区域的特点)的位置。在第二阶段进一步分析这些大规模的痕迹。连续小波变换(CWT)用于定位不同尺度上的色谱峰。


值----------Value----------

A matrix with columns:
一个矩阵的列:


参数:mz
weighted (by intensity) mean of peak m/z across scans  
加权(强度)意味着整个扫描峰的m / z


参数:mzmin
m/z peak minimum  
的m / z峰最低


参数:mzmax
m/z peak maximum   
m / z为最大峰值


参数:rt
retention time of peak midpoint  
高峰期的中点的保留时间


参数:rtmin
leading edge of peak retention time  
峰的保留时间的领先优势


参数:rtmax
trailing edge of peak retention time  
峰的保留时间后缘


参数:into
integrated peak intensity  
综合峰的强度


参数:intb
baseline corrected integrated peak intensity  
基线校正集成峰值强度


参数:maxo
maximum peak intensity   
最大峰值强度


参数:sn
Signal/Noise ratio, defined as (maxo - baseline)/sd, where <br> maxo is the maximum peak intensity, <br> baseline the estimated baseline value and <br> sd the standard deviation of local chromatographic noise.  
信号/噪声比,定义(maxo - baseline)/sd,其中参考maxo是最大峰值强度,参考baseline估计的基线值和参考sd当地色谱噪声的标准偏差。


参数:egauss
RMSE of Gaussian fit
均方根误差的高斯拟合


参数:
if verbose.columns is TRUE additionally :  
如果verbose.columns是TRUE此外:


参数:mu
Gaussian parameter mu
高斯参数亩;


参数:sigma
Gaussian parameter sigma
高斯参数西格马


参数:h
Gaussian parameter h
高斯参数h


参数:f
Region number of m/z ROI where the peak was localised
区域的m / z的投资回报率是本地化的高峰


参数:dppm
m/z deviation of mass trace across scans in ppm
跨ppm的扫描质量跟踪的m / z偏差


参数:scale
Scale on which the peak was localised
尺度上的本地化高峰


参数:scpos
Peak position found by wavelet analysis
小波分析发现峰的位置


参数:scmin
Left peak limit found by wavelet analysis (scan number)
小波分析发现左峰限制(扫描数)


参数:scmax
Right peak limit found by wavelet analysis (scan number)
小波分析发现右峰限制(扫描数)


方法----------Methods----------

     findPeaks.centWave(object, ppm=25, peakwidth=c(20,50), snthresh=10,     prefilter=c(3,100), mzCenterFun="wMean", integrate=1, mzdiff=-0.001, fitgauss=FALSE,     scanrange= numeric(), noise=0, sleep=0, verbose.columns=FALSE)   
     findPeaks.centWave(object, ppm=25, peakwidth=c(20,50), snthresh=10,     prefilter=c(3,100), mzCenterFun="wMean", integrate=1, mzdiff=-0.001, fitgauss=FALSE,     scanrange= numeric(), noise=0, sleep=0, verbose.columns=FALSE)   


作者(S)----------Author(s)----------


Ralf Tautenhahn



参考文献----------References----------

"Highly sensitive feature detection for high resolution LC/MS" BMC Bioinformatics 2008, 9:504

参见----------See Also----------

findPeaks-methods xcmsRaw-class
findPeaks-methodsxcmsRaw-class

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。
回复

使用道具 举报

您需要登录后才可以回帖 登录 | 注册

本版积分规则

手机版|小黑屋|生物统计家园 网站价格

GMT+8, 2025-1-22 18:48 , Processed in 0.027986 second(s), 15 queries .

Powered by Discuz! X3.5

© 2001-2024 Discuz! Team.

快速回复 返回顶部 返回列表