r - R：Vioplot 给出 cut() 错误

Question

我正在尝试使用 vioplot 为我想比较的两个不同组的几列生成图：

for (i in 19:length(data) ) {
    # violin plot
    vioplot(data[[1]][[i]], data[[2]][[i]], col="grey", names=names(data),     colMed="Green")
    # Calculate means
    means <- tapply(data[[i]], data[["category"]], mean)
    # Plot mean points.
    points(means, col="red", pch=16)
    # legend for median and mean in topright corner of plot.
    legend('topright', c("median","mean"), pch=16, col=c("green","red"))
}

但是，我收到以下错误：

Error in cut.default(x, breaks = breaks) : 'breaks' are not unique
Calls: vioplot ... sm.density -> binning -> binning.1d -> cut -> cut.default

我认为这可能与此处描述的某些数据列的分位数相等有关： Cut() error - 'breaks' is not unique

有没有办法让 vioplot 忽略这些情况或强制情节？

谢谢！