我有一个玩具功能,
foo
,这只是给变量加5
x
我还有第二个功能,
n_foo
这适用
foo
a
data.table
n
时间。其工作原理如下:
# Load library
library(data.table)
# Dummy function
foo <- function(x){
x + 5
}
# Apply foo n times
n_foo <- function(x, n){
Reduce(function(a, b) foo(a), 1:n, init = x)
}
# Dummy data
dt <- data.table(values = 1:10)
# Run foo 5 times
dt[, test := n_foo(.SD, 5)]
# See results
dt
#> values test
#> 1: 1 26
#> 2: 2 27
#> 3: 3 28
#> 4: 4 29
#> 5: 5 30
#> 6: 6 31
#> 7: 7 32
#> 8: 8 33
#> 9: 9 34
#> 10: 10 35
太棒了现在,说有点不对劲,我想调试一下
n_foo
,我会拿出信托
debug
功能。
警告:以下代码可能会使您的会话崩溃。
# Load library
library(data.table)
# Dummy function
foo <- function(x){
x + 5
}
# Apply foo n times
n_foo <- function(x, n){
Reduce(function(a, b) foo(a), 1:n, init = x)
}
# Dummy data
dt <- data.table(values = 1:10)
debug(n_foo)
# Run foo 5 times
dt[, test := n_foo(.SD, 5)]
# See results
dt
生产,
奇怪的是,会议
不
如果使用以下命令运行此代码,则会崩溃
reprex
。为什么此代码会导致致命错误?
编辑:
事实证明,我只能在RStudio和
不
在CLI上。RStudio标签已相应添加。
R version 4.0.0 (2020-04-24)
Platform: x86_64-apple-darwin17.0 (64-bit)
Running under: macOS Catalina 10.15.5
Matrix products: default
BLAS: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib
locale:
[1] en_CA.UTF-8/en_CA.UTF-8/en_CA.UTF-8/C/en_CA.UTF-8/en_CA.UTF-8
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
[1] data.table_1.12.8
loaded via a namespace (and not attached):
[1] compiler_4.0.0 tools_4.0.0
