在dygraphs中实现堆叠柱状图时遇到数值类型报错的求助

我有一个xts格式的数据框，结构如下：

structure(c("May 2022", "Jun 2022", "Jul 2022", "Aug 2022", "Sep 2022",
"Oct 2022", "Nov 2022", "Dec 2022", " 3035.199", " 5500.000",
"11568.750", " 2510.000", " 6999.999", "21792.149", " 9750.000",
" 5624.999", " 2250.000", " 4136.975", " 6525.500", " 2771.875",
" 4637.500", "16273.499", " 6000.000", " 4494.649", " 2500.000",
"    0.000", " 3029.000", " 2803.500", "    0.000", "14481.250",
" 4374.998", " 4062.498", "    0.000", " 3075.000", " 6939.249",
" 1500.000", " 4183.157", " 5769.000", " 3559.500", " 3250.000"
), class = c("xts", "zoo"), index = structure(c(1651363200, 1654041600,
1656633600, 1659312000, 1661990400, 1664582400, 1667260800, 1669852800
), tzone = "UTC", tclass = "yearmon"), .Dim = c(8L, 5L), .Dimnames = list(
NULL, c("Month", "Cat 1", "Cat 2", "Cat 3", "Cat 4")))

我想用dygraphs库创建一个堆叠柱状图，目前写的代码是这样的：

library(dygraphs)
library(lubridate)

today <- as.Date(Sys.time())
last_6 <- today+months(-6)

dygraph(df) %>%
dyAxis("y", label= "Total") %>%
dyRangeSelector(dateWindow = c(last_6, today)) %>%
dyMultiColumnGroup(c("Cat 1", "Cat 2", "Cat 3", "Cat 4"))

这段代码能生成普通的分组柱状图，但我想要的是堆叠样式的。

之后我尝试把dyMultiColumnGroup那一行替换成dyStackedBarGroup(c("Cat 1", "Cat 2", "Cat 3", "Cat 4"))，结果直接报错了：

Error in cumulativeYval + points : non-numeric argument to binary operator

我查了一些教程，很多都提到要用到plotters，但讲得太笼统了，我完全搞不懂具体该怎么操作。有没有大佬能给我一些实用的建议呀？

备注：内容来源于stack exchange，提问作者alec22