如何使用向量中的每个值作为平均值在R中重复dnorm？

我有一个向量：

chbin <- seq (from = 0, to = 10, by = 0.02)

我需要创建一个数据帧。 数据帧的每一行应该有45个值，其中第一个值是

dnorm（chbin，mean=（chmean[1]），sd=（cherr[1]，log=FALSE）

，第二个值是

dnorm（chbin，mean=（chmin[2]），sd=（cherr[2]，log=FALSE）

，依此类推到

dnorm（chbin，mean=（chbin，mean[45]），sd=（cherr log=FALSE）

。也就是说，对于chbin中的每个值，dnorm计算45次，对于chmean中的每个值和cherr中的相应值，计算一次。

---

结果数据框将有45列，行数与chbin中的值相同。

您可以使用以下嵌套for循环：

chbin <- seq (from = 0, to = 10, by = 0.02)
chmean <- seq (from = 1, to = 2, by = 0.02)
cherr <- seq (from = 1, to = 2, by = 0.02)

foo <- data.frame(matrix(0, nrow=length(chbin), ncol=length(chmean)) )

for(i in 1:length(chbin) ){
 for(j in 1:length(chmean) ){
  foo[i,j] <- dnorm(chbin[i], mean = chmean[j], sd = cherr[j], log=FALSE) 
 }
}

---

chbin您可以使用以下嵌套for循环：

chbin <- seq (from = 0, to = 10, by = 0.02)
chmean <- seq (from = 1, to = 2, by = 0.02)
cherr <- seq (from = 1, to = 2, by = 0.02)

foo <- data.frame(matrix(0, nrow=length(chbin), ncol=length(chmean)) )

for(i in 1:length(chbin) ){
 for(j in 1:length(chmean) ){
  foo[i,j] <- dnorm(chbin[i], mean = chmean[j], sd = cherr[j], log=FALSE) 
 }
}

chbin
mapply
可用于解决该问题：

chbin <- seq(from = 0, to = 10, by = 0.02)
chmean <- seq(from = 1, to = 2, by = 0.02)
cherr <- seq(from = 1, to = 2, by = 0.02)    

foo <- mapply(function(mean,sd) dnorm(chbin,mean,sd), mean=chmean, sd=cherr)

chbin
mapply
可用于解决该问题：

chbin <- seq(from = 0, to = 10, by = 0.02)
chmean <- seq(from = 1, to = 2, by = 0.02)
cherr <- seq(from = 1, to = 2, by = 0.02)    

foo <- mapply(function(mean,sd) dnorm(chbin,mean,sd), mean=chmean, sd=cherr)

chbin