长变量名是否会降低r的性能？

Question

例如,如果在运行数百万次试验的函数中,以下两种运行速度会不同.

the.name.of.a.random.variable.in.r <- some.value

variable <- some.value

然后扩展这个如何与函数名称相关.

Answer 1

我的简单基准测试实验表明它并不重要:

the.name.of.a.random.variable.in.r <- 1:1000
the.name.of.a.random.variable.in.r.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa <- 1:1000

variable <- 1:1000

microbenchmark::microbenchmark(long=sum(the.name.of.a.random.variable.in.r), 
                               short=sum(variable), 
                               verylong=sum(the.name.of.a.random.variable.in.r.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa))

# Unit: nanoseconds
# expr     min  lq    mean median     uq   max neval cld
# long     970 987 1147.48 1036.5 1057.5 10468   100   a
# short    969 985 1038.82 1030.5 1053.5  1841   100   a
# verylong 968 988 1070.16 1036.0 1062.5  3961   100   a