RCS plot 包内置数据集使用时报错
```r
> # 加载包
> library(tibble)
> library(dplyr)
> library(survival)
> library(plotRCS)
> head(cancer)
id age sex race size metastasis status time
1 10274 53 Male White 27 No Censored 12
2 56998 32 Male Black 185 No Dead 5
3 60010 69 Male White 51 No Dead 13
4 24307 61 Male White 37 No Censored 50
5 5253 53 Female White 25 No Censored 27
6 39685 56 Male Other 38 No Censored 17
> summary(cancer)
id age sex race size metastasis status
Length:903 Min. :20.00 Female:211 White:621 Min. : 4.00 No :790 Censored:321
Class :character 1st Qu.:57.00 Male :692 Black:143 1st Qu.: 29.00 Yes:113 Dead :582
Mode :character Median :63.00 Other:139 Median : 45.00
Mean :62.57 Mean : 59.03
3rd Qu.:70.00 3rd Qu.: 78.00
Max. :80.00 Max. :240.00
time
Min. : 0.00
1st Qu.: 4.00
Median :15.00
Mean :21.22
3rd Qu.:32.00
Max. :83.00
> # 执行分析
> rcsplot(data = cancer,
+ outcome = "status",
+ time = "time",
+ exposure = "age",
+ covariates = c("sex", "race"))
Error in reformulate(attr(termobj, "term.labels")[-dropx], response = if (keep.response) termobj[[2L]], :
'termlabels'必需是长度至少为一的字节矢量
```