自定义填充 geom_density_gradient 填充

Question

我有这种形式的数据

Iteration Chain Parameter                           value
       <int> <int> <fct>                               <dbl>
 1         1     1 r_ROI__DESCENT[OFC_dlPFC,AGEz] -2.22     
 2         3     1 r_ROI__DESCENT[OFC_dlPFC,AGEz] -2.22     
 3         5     1 r_ROI__DESCENT[OFC_dlPFC,AGEz] -2.09     
 4         7     1 r_ROI__DESCENT[OFC_dlPFC,AGEz]  0.0000535
 5         9     1 r_ROI__DESCENT[OFC_dlPFC,AGEz] -0.00771  
 6        11     1 r_ROI__DESCENT[OFC_dlPFC,AGEz]  0.00262  
 7        13     1 r_ROI__DESCENT[OFC_dlPFC,AGEz] -0.0549   
 8        15     1 r_ROI__DESCENT[OFC_dlPFC,AGEz] -0.0209   
 9        17     1 r_ROI__DESCENT[OFC_dlPFC,AGEz] -0.0649   
10        19     1 r_ROI__DESCENT[OFC_dlPFC,AGEz] -0.0393   

尝试在此值列上绘制 geom_density_gradient

ggplot(
  df, 
  aes(x = value, y = Parameter, fill = as.factor(df$pd))
) +
  geom_density_ridges_gradient(scale = 2, size = 0.7, rel_min_height = .001) +
  scale_fill_viridis_c(option = "C")+
  geom_vline(xintercept = 0, col = "black", size = 1)+
  xlim(-.3,.3)+
  theme_bw()

我希望填充函数采用第二个数据中的 pd 值

Parameter     |   Mean | CI_low | CI_high |     pd
--------------------------------------------------
r_ROI__DESCENT[OFC_dlPFC,AGEz]   | -0.013 | -0.081 |   0.048 | 67.73%
r_ROI__DESCENT[OFC_AMG,AGEz]   |  0.066 | -0.009 |   0.142 | 96.51%
r_ROI__DESCENT[OFC_PCN,AGEz] | -0.034 | -0.106 |   0.027 | 87.72%

它说行不匹配，但我如何选择一个与参数名称对应的值用作填充渐变？