R：是否可以绑定非数字列

Question

library(Rmpfr)
mynumber <- new("mpfr", .Data = list(new("mpfr1", prec = 50L, exp = c(1045L, 
0L), sign = 1L, d = c(151748608L, -358118319L)), new("mpfr1", 
    prec = 50L, exp = c(20L, 0L), sign = 1L, d = c(-1114947584L, 
    -1905679017L)), new("mpfr1", prec = 50L, exp = c(-55L, -1L
), sign = 1L, d = c(-1449918464L, -906197701L)), new("mpfr1", 
    prec = 50L, exp = c(221L, 0L), sign = 1L, d = c(819707904L, 
    -1329031570L))))

mynumber是其中包含4个数字的类mpfr对象。我想以0列表示cbind mynumber，即

> cbind(rep(0, 4), mynumber)
       mynumber
[1,] 0 ?       
[2,] 0 ?       
[3,] 0 ?       
[4,] 0 ?  

这给了我？？？？在第二列中，因此我尝试将mynumber更改为类numeric首先

mydata <- cbind(rep(0, 4), sapply(mynumber, asNumeric))
> mydata
     [,1]         [,2]
[1,]    0          Inf
[2,]    0 5.833223e+05
[3,]    0 2.189941e-17
[4,]    0 2.327185e+66

但是，由于mynumber中的第一个数字确实很大，因此使用asNumeric将其改为Inf。

编辑：我的最终目标是运行：

mydata <- cbind(rep(0, 4), sapply(mynumber, asNumeric))
> mydata/rowSums(mydata)
     [,1] [,2]
[1,]    0  NaN
[2,]    0    1
[3,]    0    1
[4,]    0    1

并且没有打印出NaN。

Answer 1

一种选择是用list包装，然后创建一个tibble/data.frame对象，因为cbind转换为matrix，并且matrix只能容纳一个类

library(tibble)
tibble(col1 = 0, col2 = list(mynumber))
# A tibble: 1 x 2
#   col1 col2  
#  <dbl> <list>
#1     0 <mpfr>

---

即使是cbind和character类的[numeric也会为所有列返回character，当要绑定的vector属于不同类时，这不是一个好选择

cbind(letters[1:4], 1:4)

---

在装入程序包后通过检查methods中的cbind

methods('cbind')
#[1] cbind,ANY-method     cbind,Mnumber-method cbind.bigq*          cbind.bigz*         
#[5] cbind.data.frame     cbind.grouped_df*    cbind.ts*       

因此，如果它对cbind使用了正确的Mnumber方法，则不应给出Inf

cbind(rep(0,4),  mynumber)
#'mpfrMatrix' of dim(.) =  (4, 2) of precision  50 .. 53  bits 
#     [,1] [,2]                   
#[1,]   0. 3.4556867084990952e+314
#[2,]   0.      583322.33392099757
#[3,]   0.  2.1899410233914937e-17
#[4,]   0.  2.3271850367397449e+66

或利用价值的循环利用

cbind(0,  mynumber)
#'mpfrMatrix' of dim(.) =  (4, 2) of precision  50 .. 53  bits 
#     [,1] [,2]                   
#[1,]   0. 3.4556867084990952e+314
#[2,]   0.      583322.33392099757
#[3,]   0.  2.1899410233914937e-17
#[4,]   0.  2.3271850367397449e+66

---

此外，如果我们检查掩盖的功能，则在加载程序包时会说

以下对象从'package：base'中被屏蔽：

cbind，pmax，pmin，rbind

通过使用cbind中的base，可以复制?。对于OP，cbind来自base

base::cbind(0, mynumber)
#       mynumber
#[1,] 0 ?       
#[2,] 0 ?       
#[3,] 0 ?       
#[4,] 0 ?       

如果cbind中的Rmpfr被屏蔽，则使用::

mydata <- Rmpfr::cbind(0, mynumber)
mydata
#'mpfrMatrix' of dim(.) =  (4, 2) of precision  50 .. 53  bits 
#     [,1] [,2]                   
#[1,]   0. 3.4556867084990952e+314
#[2,]   0.      583322.33392099757
#[3,]   0.  2.1899410233914937e-17
#[4,]   0.  2.3271850367397449e+66




mydata/rowSums(mydata)
#'mpfrMatrix' of dim(.) =  (4, 2) of precision  53   bits 
#     [,1] [,2]              
#[1,]   0. 1.0000000000000000
#[2,]   0. 1.0000000000000000
#[3,]   0. 1.0000000000000000
#[4,]   0. 1.0000000000000000

Answer 2

我想知道您创建的对象是否存在问题。当我更改它以确保每个exp字段都只有一个值时，我得到了所需的结果：

library(Rmpfr)

x <- new("mpfr", .Data = list(new("mpfr1", prec = 50L, exp = 1045L, 
    sign = 1L, d = c(151748608L, -358118319L)), new("mpfr1", 
    prec = 50L, exp = 20L, sign = 1L, d = c(-1114947584L, -1905679017L
    )), new("mpfr1", prec = 50L, exp = -55L, sign = 1L, d = c(-1449918464L, 
-906197701L)), new("mpfr1", prec = 50L, exp = 221L, sign = 1L, 
    d = c(819707904L, -1329031570L))))

cbind(c(0, 0, 0, 0), x)
#> 'mpfrMatrix' of dim(.) =  (4, 2) of precision  50 .. 53  bits 
#>      [,1] [,2]                   
#> [1,]   0. 3.4556867084990952e+314
#> [2,]   0.      583322.33392099757
#> [3,]   0.  2.1899410233914937e-17
#> [4,]   0.  2.3271850367397449e+66

^{由reprex package（v0.3.0）在2020-02-29创建}

Answer 3

zeros <- mpfr(c(0,0,0,0), precBits = getPrec(mynumber))
M <- cbind(mynumber, zeros)
M %*% t(M) # just to try