有的时候将DataFrame中的多列数据变层两列和三列数据进行画图，这种操作称为melt, 在R和python中都有实现，记录如下
R将两列合并成一列df=data.frame(v1=c(1,2,3),v2=c("2","2","100"))
df
reshape2::melt(df,id.vars=NULL)
结果如下
samplesize=c(1000,2000,5000,10000,20000,40000,50000,100000,300000,500000,1000000,1300000)
methods=c("DESC","DESC_GPU","DESC_multicpu","scVI","scVI_GPU","scVI_multicpu","Seurat3.0")
f_mem=function(x){
t1= x/100000
t2 =x/110000
t3= x/200000
t4= x/140000
t2 =x/500000
t5 =x/400000
t6= x/90000
t7= x/20000
mem =data.frame(samplesize=samplesize,t1=t1,t2=t2,t3=t3,t4=t4,t5=t5,t6=t6,t7=t7)
colnames(mem)=c("samplesize",methods)
return(mem)
}
mem_df =f_mem(samplesize)
write.csv(mem_df,file="./mem_df.csv")
mem_df
mem_final=reshape2::melt(mem_df,id.var="samplesize")
mem_final
结果如下
mem_df=pd.read_csv("./mem_df.csv",index_col=0)
mem_df
mem_final=pd.melt(mem_df,id_vars="samplesize")
结果如下
