R中的Plot.ly:x轴的不需要的字母排序

问题描述

我尝试了几个小时，但我无法成功.我的数据框很简单

I tried for hours, but I could not succeed. My data frame is simply

df <- as.data.frame(matrix(c("g","d","a","b","z",5,4,3,2,1),5,2))

library("plotly")
p <- plot_ly(data = df,x = ~V1,y = ~V2,type = "scatter",mode = "lines+markers") %>%
layout(title = "my title")
p

所以，这个给我

但我不希望 x 轴按字母顺序排序，我只想保持原样并查看递减图.

But I don't want x axis to be sorted alphabetically, I just want to keep the order as it is and see a decreasing graph.

推荐答案

首先，一个矩阵只能保存一个类的数据.因此，您有一个要转换为 data.frame 的字符串矩阵.因为默认情况下 stringAsFactors = TRUE，您的字符矩阵将转换为 factor 的 data.frame，其中两列的级别默认排序.V1 按字母顺序排列，V2 按升序排列.

First of all, a matrix can only hold data of one class. Hence you have a matrix of strings that you are converting to a data.frame. Because by default stringAsFactors = TRUE, your character matrix is converted to a data.frame of factor's, where the levels of your two columns are by default sorted. Alphabetically for V1 and in increasing order for V2.

如果您不希望直接修改数据以从源头上解决问题 - 正如其他答案中指出的那样，您可以替代地使用 plotly 的 categoryorder =<layout() 中的/code> 参数，方式如下:

library(plotly)
xform <- list(categoryorder = "array",
              categoryarray = df$V1)

plot_ly(data = df,
        x = ~V1,
        y = ~V2,
        type = "scatter",
        mode = "lines+markers") %>%
        layout(title = "my title",
               xaxis = xform)