如何增加 R plot_ly 中颜色栏值的字体大小？

Question

我写了下面的代码。 如何增加颜色栏中值的字体大小，如代码后显示的图中蓝色圆圈所示？ 我已经尝试在倒数第二行的代码布局部分进行操作，但它似乎没有用。这在代码中以粗体显示。 感谢您的帮助。

library(plotly)
VSL <- c(79000, 161000, 327000)
SCC <- c(35, 50, 200)

z_data <- list(
  fig1 = matrix(
    c(0.83, 1.18, 4.69, 0.85, 1.20, 4.71, 0.88, 1.23, 4.74), 
    nrow = 3, ncol = 3),
  fig2 = matrix(
    c(0.77, 1.09, 4.31, 0.78, 1.1, 4.33, 0.81, 1.13, 4.36), 
    nrow = 3, ncol = 3),
  fig3 = matrix(
    c(0.68, 0.97, 3.85, 0.70, 0.98, 3.87, 0.72, 1.01, 3.89), 
    nrow = 3, ncol = 3),
  fig4 = matrix(
    c(0.64, 0.91, 3.60, 0.65, 0.92, 3.61, 0.67, 0.94, 3.63), 
    nrow = 3, ncol = 3))

# Define the contour properties; `start`/`end` define the min/max
# values of the shown contour range
contours <- list(
  showlabels = TRUE,
  start = floor(min(unlist(z_data))),
  end = ceiling(max(unlist(z_data))),
  labelfont = list(size = 20, color = "black"),
  size = 0.2)

m <- list(l=100, r=20, b=100, t=100) # l = left; r = right; t = top; b = bottom

# Create a `list` of `plot_ly` objects
lst <- lapply(z_data, function(z) {
  plot_ly(
    x = ~VSL, y = ~SCC, z = z,
    type = "contour", 
    coloraxis = "coloraxis", 
    contours = contours) %>%
    layout(
      xaxis = list(tickfont = list(size = 20)), 
      yaxis = list(
        tickfont = list(size = 20),
        title_font = list(size = 22) # Specify font size for y-axis title
      ),
      margin=m
      )
})

# `subplot` accepts a `list` of `plot_ly` objects 
fig <- subplot(lst, shareY = TRUE)

annotations = list( 
  list(
    x = 0.10,  
    y = 1,
    text = "$46/tCO\u2082",  
    xref = "paper",  
    yref = "paper",  
    xanchor = "center",
    yanchor = "bottom",
    showarrow = FALSE,
    font = list(
      family = "Arial, sans-serif", # change font family to one that supports subscripts
      size = 20,
      color = "black",
      parse = TRUE
    )),
  list(
    x = 0.37,
    y = 1,
    text = "$50/tCO\u2082",
    xref = "paper",
    yref = "paper",
    xanchor = "center",
    yanchor = "bottom",
    showarrow = FALSE,
    font = list(
      family = "Arial, sans-serif", # change font family to one that supports subscripts
      size = 20,
      color = "black",
      parse = TRUE
    )),
  list(
    x = 0.63,
    y = 1,
    text = "$56/tCO\u2082",
    xref = "paper",
    yref = "paper",
    xanchor = "center",
    yanchor = "bottom",
    showarrow = FALSE,
    font = list(
      family = "Arial, sans-serif", # change font family to one that supports subscripts
      size = 20,
      color = "black",
      parse = TRUE
    )),
  list(
    x = 0.89,
    y = 1,
    text = "$60/tCO\u2082",
    xref = "paper",
    yref = "paper",
    xanchor = "center",
    yanchor = "bottom",
    showarrow = FALSE,
    font = list(
      family = "Arial, sans-serif", # change font family to one that supports subscripts
      size = 20,
      color = "black",
      parse = TRUE
    )),
  list(
    x = 0.5,
    y = 1.06,
    text = "Benefit-cost analysis at varying CCS cost",
    xref = "paper",
    yref = "paper",
    xanchor = "center",
    yanchor = "bottom",
    showarrow = FALSE,
    font = list(
      family = "Arial, sans-serif", # change font family to one that supports subscripts
      size = 22,
      color = "black"
    )),
  list(
    x = 1.03,
    y = 0.99,
    text = "B-C Ratio",
    xref = "paper",
    yref = "paper",
    xanchor = "center",
    yanchor = "bottom",
    showarrow = FALSE,
    font = list(
      family = "Arial, sans-serif", # change font family to one that supports subscripts
      size = 20,
      color = "black",
      parse = TRUE
    )),
  list(
    x = 0.5,
    y = -0.08,
    text = "VSL",
    xref = "paper",
    yref = "paper",
    xanchor = "center",
    yanchor = "bottom",
    showarrow = FALSE,
    font = list(
      family = "Arial, sans-serif", # change font family to one that supports subscripts
      size = 22,
      color = "black",
      parse = TRUE
    )),
    list(
      x = -0.04,
      y = 0.5,
      text = "SCC",
      xref = "paper",
      yref = "paper",
      xanchor = "center",
      yanchor = "middle",
      showarrow = FALSE,
      font = list(
        family = "Arial, sans-serif", # change font family to one that supports subscripts
        size = 22,
        color = "black",
        parse = TRUE
      ),
      textangle = -90
    ))



fig <- fig %>% layout(**coloraxis = list(tickfont = list(size = 14)**,
                      colorscale = 'RdBu'),
                      annotations = annotations)
fig