接下来我们首先基于dune数据构造距离矩阵,需要用到的函数vegdist。 vegdist(x, method="bray",binary=FALSE, diag=FALSE, upper=FALSE, na.rm = FALSE, ...) Upper 是否显示对角线以上的值 library(vegan) data(dune) data(dune.env) dune.dist <- vegdist(dune)#构造距离矩阵。 ?
相似性的计算和vegdist函数的相同。
in 1:q) { for (j in 1:(p/3)) { commean[i, j]=mean(com[i,(3*j-2):(3*j)]) } } #计算距离矩阵 otu_dist=vegdist 3*j)]) } } otumean=t(otumean) #调整物种与环境因子样品ID顺序一致 otumean=otumean[rownames(env),] #计算距离矩阵 otu_dist=vegdist
11data(varespec) 12vare.dist <- vegdist(wisconsin(varespec)) 13mds.null <- monoMDS(vare.dist, y = cmdscale
6bias.adjust:校准小样本偏差 7sqrt.dist:不相似性计算平方根 例子 1data(varespec) 2## 算Bray-Curtis distances 3dis <- vegdist
data[,1] data=data[,-1] library(vegan) data=decostand(data, MARGIN=2, "total") otu=t(data) otu_dist=vegdist data[,1] data=data[,-1] library(vegan) data=decostand(data, MARGIN=2, "total") otu=t(data) otu_dist=vegdist
row.names = 1, header=T) dim(inMBss) 使用vegan包做PCoA分析 library(vegan) distMatrix <- vegdist
man gow bra kul 0.2396330 0.2735087 0.2288358 0.2837910 0.2839834 > vare.dis <- vegdist
dplyr) + vars <- colnames(env) + models<-list() + for (i in seq_along(vars)){ + otu_bray<-vegdist (otu,method = "bray") + env_dis<-vegdist(env[vars[i]],method = "euclidean") + model <- mantel
~ 'South', TRUE ~ 'axis' )) -> new.group 这个分组信息可能和原文中有差别 主坐标分析代码 library(vegan) distance <- vegdist
Anosim分析使用距离进行分析,默认为method="bray",可以选择其他距离(和vegdist()函数相同),也可以直接使用距离矩阵进行分析。
means=apply(data, 1, mean) otu=data[names(means[means>10]),] otu=t(otu) #计算距离矩阵 library(vegan) dist=vegdist
data[,1] data=data[,-1] library(vegan) data=decostand(data, MARGIN=2, "total") otu=t(data) otu_dist=vegdist
p.adjust(). dune.pairwise.adonis <- pairwise.adonis(x=dune, factors=dune.env$Management, sim.function = "<em>vegdist</em>
下面我们以生态学领域我们常用vegan包中的vegdist()函数为例,此函数使用方法如下所示: vegdist(x, method="bray", binary=FALSE, diag=FALSE,
将每个样品的物种数据进行总和标准化(即求相对丰度) library(vegan) data=decostand(data, MARGIN=2, "total")*100 otu=t(data) #计算距离矩阵 otu_dist=vegdist
vegdist评估数据离散度,再解释adonis的结果 前面我们用下面的代码检验了Managment对物种组成差异影响的显著程度,获得P-value=0.002 < 0.05,表示管理方式对物种组成有显著影响 # 计算加权bray-curtis距离 dune.dist <- vegdist(dune, method="bray", binary=F) # One measure of multivariate # 计算加权bray-curtis距离 otu_dist <- vegdist(otu_table_t, method="bray", binary=F) otu_pcoa <- cmdscale(otu_dist
For other method, refer to vegdist() # this function is to prepare metadata-added coordinates dataframe bray_dist <- vegan::vegdist(mat, dist_method) coordinates <- as.data.frame(ape::pcoa(bray_dist)$vectors For other method, refer to vegdist(). # fsize: the font size, [int]. # dsize: the dot size, [int] For other methods, refer to vegdist().fsize: the font size of labels, [int]. default: [11]dsize: the
将每个样品的物种数据进行总和标准化(即求相对丰度) library(vegan) data=decostand(data, MARGIN=2, "total")*100 otu=t(data) #层次聚类 otu_dist=vegdist
SPRING (SPRING package) gCoda (R code on GitHub) propr (propr package) 「相异度计算方法:」 Euclidean distance (vegdist () from vegan package) Bray-Curtis dissimilarity (vegdist() from vegan package) Kullback-Leibler divergence Compositional KLD (own implementation following [Martín-Fernández et al., 1999]) Aitchison distance (vegdist