如何随机抽样2个重量在0.5-1.0之间的报告
也;如何随机抽样20%的权重介于0.5 - 1.0之间的报告
DF <- data.frame(Report_ID=c(2,8,12,15,16, 51,67,89,88,98),
Weight=c(0.05,0.1,0.25,0.30,0.35,0.56,0.75,0.81,0.95,1.0))
使用dplyr
:
library(dplyr)
样本2报告:
DF %>%
filter(between(Weight, 0.5, 1)) %>%
sample_n(2)
样本的20%报告:
DF %>%
filter(between(Weight, 0.5, 1)) %>%
sample_frac(0.5)
你可以试试这个:
rand_sample <- DF[ sample( which(DF$Weight > 0.4 & DF$Weight < 1.1), round(0.2*length(which(DF$Weight > 0.4 & DF$Weight < 1.1)))), ]