博文
记着用 lapply(base)
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在R里做循环操作，似乎可以放弃 for 这样的循环语句。lapply(base) 应该是首选途径。事实上lapply(base)是个家族。让我们看看它们的成员与用法：
Description (描述)
lapply
returns a list of the same length as X, each element of which is the result of applying FUN to the corresponding element of X.
sapply
is a user-friendly version of lapply by default returning a vector or matrix if appropriate.
replicate
is a wrapper for the common use of sapply for repeated evaluation of an expression (which will usually involve random number generation).
Usage (用法)
lapply(X, FUN, ...)
sapply(X, FUN, ..., simplify = TRUE, USE.NAMES = TRUE)
replicate(n, expr, simplify = TRUE)
Arguments (参数设置)
X
a vector (atomic or list) or an expressions vector. Other objects (including classed objects) will be coerced by as.list.
FUN the function to be applied to each element of X: see ‘Details’. In the case of functions like +, %*%, etc., the function name must be backquoted or quoted.
... optional arguments to FUN.
simplify logical;
should the result be simplified to a vector or matrix if possible?
USE.NAMES logical;
if TRUE and if X is character, use X as names for the result unless it had names already.
n
number of replications.
expr
expression (language object, usually a call) to evaluate repeatedly.
https://m.sciencenet.cn/blog-352360-345949.html
上一篇：强大的，做permutation test的R包 - perm
下一篇：记着用 ddply(plyr)
Description (描述)
lapply
returns a list of the same length as X, each element of which is the result of applying FUN to the corresponding element of X.
sapply
is a user-friendly version of lapply by default returning a vector or matrix if appropriate.
replicate
is a wrapper for the common use of sapply for repeated evaluation of an expression (which will usually involve random number generation).
Usage (用法)
lapply(X, FUN, ...)
sapply(X, FUN, ..., simplify = TRUE, USE.NAMES = TRUE)
replicate(n, expr, simplify = TRUE)
Arguments (参数设置)
X
a vector (atomic or list) or an expressions vector. Other objects (including classed objects) will be coerced by as.list.
FUN the function to be applied to each element of X: see ‘Details’. In the case of functions like +, %*%, etc., the function name must be backquoted or quoted.
... optional arguments to FUN.
simplify logical;
should the result be simplified to a vector or matrix if possible?
USE.NAMES logical;
if TRUE and if X is character, use X as names for the result unless it had names already.
n
number of replications.
expr
expression (language object, usually a call) to evaluate repeatedly.
https://m.sciencenet.cn/blog-352360-345949.html
上一篇：强大的，做permutation test的R包 - perm
下一篇：记着用 ddply(plyr)
