r - 使用 integer64 键连接错误

Question

尝试连接具有 integer64 值列作为主键的表时出现意外错误。下面说明问题——

Keys as int
-----------
x <- data.table(c1=c(1,2,3), c3=c(10,20,30))
z <- data.table(c1=c(1,2), c2=c(100,200))

setkey(x, c1)
setkey(z, c1)

> z[x]          # Join works fine

   c1  c2 c3
1:  1 100 10
2:  2 200 20
3:  3  NA 30


As integer64
------------

library(bit64)
x[,c1:=as.integer64(c1)]
z[,c1:=as.integer64(c1)]

setkey(x, c1)
setkey(z, c1)

> z[x]       # Same join, but generates error message

Error in vecseq(f__, len__, if (allow.cartesian) NULL else as.integer(max(nrow(x),  : 
Join results in 6 rows; more than 3 = max(nrow(x),nrow(i)). Check for duplicate key values 
in i, each of which join to the same group in x over and over again. If that's ok, try 
including `j` and dropping `by` (by-without-by) so that j runs for each group to avoid the 
large allocation. If you are sure you wish to proceed, rerun with allow.cartesian=TRUE. 
Otherwise, please search for this error message in the FAQ, Wiki, Stack Overflow and 
datatable-help for advice.

关于问题可能是什么的任何想法？我在更大的 table 上遇到同样的错误。作为一种解决方法，我不得不将 integer64 值转换为字符，然后才能正常工作。

> sessionInfo()
R version 3.0.1 (2013-05-16)
Platform: x86_64-apple-darwin10.8.0 (64-bit)

... 
other attached packages:
[1] bit64_0.9-2       bit_1.1-10        cluster_1.14.4    skmeans_0.2-4     ggplot2_0.9.3.1  
[6] data.table_1.8.11

提前致谢。

Answer 1

只是为了回答一个开放性问题。现在(1.9.5)按预期处理。
您在 integer64 列上的连接返回与数字字段上的连接相同的结果。