data.table不处理integer64 in by语句 [英] data.table is not handling integer64 in by statement
问题描述
正确使用data.table加载 integer64
中的 fread
,虽然我有这样的印象: by
语句不能正确处理int64。
我可能在这里做错了什么,是什么?
Using fread
from data.table load integer64
correctly, though I have the impression that by
statements are not handling int64 correctly.
I am probably doing someting wrong here, what is it ?
library(data.table); library(bit64);
test = data.table(x=c(1,2,3),y=c('x','q','q'),ID=as.integer64(c('432706205348805058','432706205348805058','432706205348805059')))
str(test) #the display is wrong (BUT IT IS EXPECTED)
#Classes ‘data.table’ and 'data.frame': 3 obs. of 3 variables:
# $ x : num 1 2 3
# $ y : chr "x" "q" "q"
# $ ID:Class 'integer64' num [1:3] 9.52e-280 9.52e-280 9.52e-280
# - attr(*, ".internal.selfref")=<externalptr>
test # Here it is displayed correctly
# x y ID
#1: 1 x 432706205348805058
#2: 2 q 432706205348805058
#3: 3 q 432706205348805059
txtR) test$ID
integer64
[1] 432706205348805058 432706205348805058 432706205348805059
txtR) test[,list(count=.N),by=ID] #WRRRONG
ID count
1: 432706205348805058 3
推荐答案
更新:现在在v1.9.3(可从R-Forge获得)中实现,参见 NEWS :
Update: This is now implemented in v1.9.3 (available from R-Forge), see NEWS :
o
bit64 :: integer64
现在可以在分组和联接中使用#5369。感谢James Sams强调UPC和Clayton Stanley。
提醒:fread()
已经能够检测并读取integer64
o
bit64::integer64
now works in grouping and joins, #5369. Thanks to James Sams for highlighting UPCs and Clayton Stanley.
Reminder:fread()
has been able to detect and readinteger64
for a while.
在上面的OP示例上:
test[, .N, by=ID]
# ID N
# 1: 432706205348805058 2
# 2: 432706205348805059 1
integer64 $ c $对于
data.table
操作尚未实现 setkey
或 / code>。它只是在
fread
中实现(首先于2013年3月6日发布到CRAN)作为第一步。例如,它可以用作值列。
integer64
isn't yet implemented for data.table
operations such as setkey
or by
. It was just implemented in fread
only (first released to CRAN on 6 March 2013) as a first step. It could be useful as a value column for example.
我可能通过提交与此相关的错误报告(@Arun链接到的)来混淆事情。严格地说,它不是一个错误,而是一个功能请求。我认为错误列表更像是在下一个版本之前解决的重要事情。
I may have confused matters by filing a bug report relating to this (the one @Arun linked to). Strictly speaking, it isn't a bug but a feature request. I think of the bug list more like 'important things to resolve before the next release'.
非常欢迎这些贡献。
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