从绘图中检索轴刻度信息 [英] Retrieve axis tick information from a plotly figure

问题描述

我正在使用R plotly绘制热图:

I'm plotting a heatmap using R plotly:

set.seed(1)
df <- reshape2::melt(matrix(rnorm(100*20),100,20,dimnames = list(paste0("G",1:100),paste0("S",1:20))))

library(plotly)
library(dplyr)
plot_ly(z=c(df$value),x=df$Var2,y=df$Var1,colors=grDevices::colorRamp(c("darkblue","gray","darkred")),type="heatmap",colorbar=list(title="Scaled Value",len=0.4)) %>%
  layout(yaxis=list(title=NULL),xaxis=list(tickangle=90,tickvals=10,ticktext="X-Label"))

如您所见，plotly并未显示所有y轴刻度线.我的问题是，是否有可能，如果可以的话，如何检索选择显示的Y轴刻度标签plotly?

As you can see, plotly is not showing all y-axis ticks. My question is whether it is possible, and if so how, to retrieve the y-axis tick labels plotly selected to show?

我保存了绘图对象:

plotly.obj <- plot_ly(z=c(df$value),x=df$Var2,y=df$Var1,colors=grDevices::colorRamp(c("darkblue","gray","darkred")),type="heatmap",colorbar=list(title="Scaled Value",len=0.4)) %>%
  layout(yaxis=list(title=NULL),xaxis=list(tickangle=90,tickvals=10,ticktext="X-Label"))

然后环顾四周，似乎plotly.obj$x$layoutAttrs应该存储此信息，但事实并非如此:

And looked around and it seems that perhaps plotly.obj$x$layoutAttrs should store this information but it doesn't:

> plotly.obj$x$layoutAttrs
$`102ce55fd393e`
$`102ce55fd393e`$yaxis
$`102ce55fd393e`$yaxis$title
NULL


$`102ce55fd393e`$xaxis
$`102ce55fd393e`$xaxis$tickangle
[1] 90

$`102ce55fd393e`$xaxis$tickvals
[1] 10

$`102ce55fd393e`$xaxis$ticktext
[1] "X-Label"

有什么主意吗?

推荐答案

我认为您无法获得刻度线，这些刻度线最终被渲染.但是您可以获得y轴可以选择的所有水平轴.

I don't think you can get the ticks, that are finally rendered. But you can get all the levels of the y-axis, that ploty can choose from.

levels(plotly.obj$x$attrs$`2c4c148651ae`$y)

最终绘制的刻度线是动态选择的，并将根据您的绘图大小等进行调整.

The ticks that are finally rendered are dynamically chosen and will adapt, depending on your plot size etc.

您还可以使用plotly_json()签出属性:

You can also check out the attributes with plotly_json():

plot_ly(z=c(df$value),x=df$Var2,y=df$Var1,colors=grDevices::colorRamp(c("darkblue","gray","darkred")),type="heatmap",colorbar=list(title="Scaled Value",len=0.4)) %>%
      layout(yaxis=list(title=NULL),xaxis=list(tickangle=90,tickvals=10,ticktext="X-Label")) %>% 
      plotly_json()

这篇关于从绘图中检索轴刻度信息的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！