Example 1: Basic Application of which FunctionExample 1 illustrates how to use the which() function in the R programming language. First, we have to create some example data:x <- c(1, 5, 4, 8, 4) # Create example vector x # Print example vector # 1 5 4 8 4...
Apply a function to vector dataDan Kelley
> 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 a matrix 1. 2. 3. 4. 5. 6. 7. 8. 9...
The apply() function can be feed with many functions to perform redundant application on a collection of object (data frame, list, vector, etc.). The purpose of apply() is primarily to avoid explicit uses of loop constructs.apply函数的重要作用就是把一个函数给一群数据应用上，这个一群数据可...
Apply a Function Over Values in an Environment对环境中的值使用函数 eapply(env, FUN, ..., all.names = FALSE, USE.NAMES = TRUE) mapply Apply a Function to Multiple List or Vector Arguments对多个列表或者向量参数使用函数 mapply(FUN, ..., MoreArgs = NULL, SIMPLIFY = TRUE, USE.NAMES = ...
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, et...
Returns a vector or array or list of values obtained by applying a function to margins of an ...
在使用R时,要尽量用array的方式思考,避免for循环。不用循环怎么实现迭代呢?这就需要用到apply函数族。它不是一个函数,而是一族功能类似的函数。概述apply系列函数的基本作用是对数组(array,可以是多维)或者列表(list)按照元素或元素构成的子集合进行迭代,并将当前元素或子集合作为参数调用某个指定函数。vector是一维...
tmp <- vector("numeric", nrow(coad_mrna_df))for(i in 1:nrow(coad_mrna_df)){ tmp[i] <- mean(as.numeric(coad_mrna_df[i,]))}head(tmp)## [1] 14.59276 14.43845 14.01330 14.04316 13.57397 13.40406 除了3个主要的参数,apply还有一个...参数,它表示:如果你要执行的操作中还有其他参数,可以...
则必须在args的位置留空apply的返回值就是函数func函数的返回值def function(a,b): print(a,b) apply...(function,('good','better')) apply(function,(2,3+6)) apply(function,('cai','quan')) apply(function...,('cai',),{'b':'caiquan'}) apply(function,(),{'a':'caiquan','b':'...