R .SD列上的data.table子集条件？

我想创建与下面的最小可复制示例相同的结果，但您可以看到最后一个代码的子集条件基本上是删除行，其中.SD列不应全部为零

library(dplyr)

library(data.table)

set.seed(1)

t1 <- sample(-1:1, 999999, replace = T) %>% matrix(ncol = 9) %>% as.data.table %>% {cbind.data.frame(id = 1:nrow(.), .)}

t1[V1 != 0|V2 != 0|V3 != 0|V4 != 0|V5 != 0|V6 != 0|V7 != 0|V8 != 0|V9 != 0, lapply(.SD, sum), by = id]

---

我们可以使用

Reduce

i1 <- t1[, .I[Reduce(`|`, lapply(.SD, `!=`, 0))], .SDcols = V1: V9]
out2 <- t1[i1, lapply(.SD, sum), by = id]

---

i1我们可以使用
Reduce

i1 <- t1[, .I[Reduce(`|`, lapply(.SD, `!=`, 0))], .SDcols = V1: V9]
out2 <- t1[i1, lapply(.SD, sum), by = id]

i1使用
rowSums（）
：

使用
rowSums（）
：

out1 <- t1[V1 != 0|V2 != 0|V3 != 0|V4 != 0|V5 != 0|V6 != 0|V7 != 0|V8 != 0|V9 != 0, lapply(.SD, sum), by = id]  
identical(out1, out2)
#[1] TRUE

t1[t1[, rowSums(.SD != 0) > 0, .SD = patterns("V\\d")]
   ][, lapply(.SD, sum), by = id]