C_1.2<- max(A[,1],A[,2]) * (unlist(B[[1]])*unlist(B[[2]])) 我想在R中创建一个列表,使用apply函数对所有可能的组合执行上述操作?我希望名字是C_j.j。我做到了以下几点: combinations <- combn(1:5, 2) result_list <- lapply(1:ncol(combinations), function(i){ j <- combinations[1...
data <- list(l1 = c(1, 2, 3, 4)) # apply the 'sum' function on data: sum_sapply1 <- sapply(data, sum) #output sum_sapply1 使用lapply查看输出的差异: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 sum_lapply1 <- lapply(data, sum) sum_lapply1 场景2:每个元素的长度>1且相同...
> z12 <- function(z) return(c(z,z^2)) > sapply(1:8,z12) [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [1,] 1 2 3 4 5 6 7 8 [2,] 1 4 9 16 25 36 49 64 # sapply(x,f) applies the function f() to each element of x and then converts the result to ...
看见没，一个输出是list另一个是向量。就这点区别。tapply() 函数 tapply() computes a measure (mean, median, min, max, etc..) or a function for each factor variable in a vector. It is a very useful function that lets you create a subset of a vector and then apply some functions to e...
Returns a vector or array or list of values obtained by applying a function to margins of an ...
mapply(rep, 1:4, 4:1) #Map #A wrapper to mapply with SIMPLIFY = FALSE, so it is guaranteed to return a list. Map(sum, 1:5, 1:5, 1:5) #rapply #Append ! to string, otherwise increment myFun <- function(x){ if (is.character(x)){ return(paste(x,"!",sep="")) } else...
(3)rapply:lapply的递归版,可以对列表中的每一个子列表中的每一个元素循环遍历,应用函数 (三)多参数计算——mapply()和map()系列函数 1、用途:对多个变量同时使用函数进行计算——Apply a Function to Multiple List or Vector Arguments 2、选项参数 ...
R语言apply()函数用法 在R语言的帮助文档里,apply函数的功能是: Retruns a vector or array or list of values obtained by applying a function to margins of an array or matrix. 就是说apply把一个function作用到array或者matrix的margins(可以理解为数组的每一行或者每一列)中,返回值时vector、array、list...
apply函数可以看作是循环的替代方法,在R语言中,apply函数的变体有很多,好多时候同学搞不清到底该用apply呢,还是tapply呢还是sapply呢。今天就给大家系统地写一写。 The apply() function can be feed with many functions to perform redundant application on a collection of object (data frame, list, vector, ...
2. Introduction to the Problem There can be a couple of scenarios when we’d like to apply a function to list elements. The first is when we want to transform the elements into other values by a function. For example, we may want to convert anIntlist to aStringlist through atoString(...