当从 selectInput 中选择变量时相关性不起作用，但在其他情况下运行得很好

Question

我正在计算 每个国家/地区 每日 Covid 病例数 和 每日疫苗接种数之间的 correlation .

有两个df，一个用于确诊病例，另一个用于疫苗接种：

library(tidyverse)
library(lubridate)
library(glue)
library(scales)
library(tidytext)
library(shiny)
library(shinydashboard)

file_url1 <- "https://raw.githubusercontent.com/johnsnow09/covid19-df_stack-code/main/ts_all_long4.csv"

file_url2 <- "https://raw.githubusercontent.com/johnsnow09/covid19-df_stack-code/main/vaccination_data.csv"

ts_all_long <- read.csv(url(file_url1))
vaccination_data <- read.csv(url(file_url2))

ts_all_long <- ts_all_long %>%
  mutate(date = as.Date(date))

vaccination_data <- vaccination_data %>%
  mutate(date = as.Date(date))

当我在 rmarkdown 中使用上述数据 运行相关性 时，它起作用了：

ts_all_long %>% 
  left_join(y = vaccination_data,
            by = c("Country.Region" = "location", "date", "continent", "iso3c" = "iso_code")) %>% 
  
  na.omit() %>% 

  group_by(Country.Region) %>% 

  summarise(COR = cor(Confirmed_daily, total_vaccinations),
            total_vaccinations_per_hundred = first(total_vaccinations_per_hundred)) %>% 
  
  
  arrange(COR) %>% 
  na.omit() %>% 
  slice(c(1:15, ( n()-14): n() ))

问题： 当我在 shiny 和 SelectInput 在 total_vaccinations 中使用它时，使 动态参数 然后它给出了这个错误：

Problem with summarise() input COR. [31mx[39m incompatible dimensions [34mi[39m Input COR is cor(Confirmed_daily, as.numeric(input$id_vaccination_type)). [34mi[39m The error occurred in group 2: Country.Region = "Argentina".

ui

fluidRow(
                 style = "border: 1px solid gray;",
                 h3("Vaccination to Cases Correlation Analysis"),
                 
                 column(4, style = "border: 1px solid gray;",
                        selectInput(inputId = "id_vaccination_type", label = "Choose Vaccination Parameter", 
                                    choices = c("total_vaccinations","people_vaccinated","people_fully_vaccinated"), 
                                    selected = "total_vaccinations")
                        ),
                 
                 column(8, style = "border: 1px solid gray;",
                        plotOutput("top_corr_countries", height = "550px") #
                 )

服务器

corr_data <- reactive({
        
        corr_data <- ts_all_long %>% 
            left_join(y = vaccination_data,
                      by = c("Country.Region" = "location", "date", "continent", "iso3c" = "iso_code")) %>% 
            
            na.omit() %>% 
            
            group_by(Country.Region) %>% 
            
            summarise(COR = cor(Confirmed_daily, as.numeric(input$id_vaccination_type)) ,
                      total_vaccinations_per_hundred = first(total_vaccinations_per_hundred)) %>% 
            na.omit() %>% 
            arrange(COR) %>% 
            na.omit() %>% 
            slice(c(1:15, ( n()-14): n() ))
    })

output$top_corr_countries <- renderPlot({
        
        corr_data() %>% 
            
            ggplot(aes(x = COR , 
                       y = fct_reorder(Country.Region, -COR),
                       col = COR > 0))  +
            geom_point(aes(size = total_vaccinations_per_hundred)) +
            geom_errorbarh(height = 0, size = 1, aes(xmin = COR, xmax = 0)) +
            geom_vline(xintercept = 0, col = "midnightblue", lty = 2, size = 1) +
            
            theme(
                panel.grid.major = element_blank(),
                legend.position = "NULL") +
            
            labs(title = glue("Top Countries by +/- Correlation with Vaccination as of {max(vaccination_data$date)}"),
                 subtitle = "Size is proportional to Vaccination per Population",
                 y = "", x = "Correlation",
                 caption = "Data source: covid19.analytics
       Created by: ViSa")
        
    })

注意：我也在另一个 link 中发布了这个问题，但它听起来更复杂，所以我试图在这个问题中重新措辞以使其更简单。

其他post：Unable to renderPlot on adding a selectInput option for variable in shiny which runs perfectly fine otherwise

Answer 1

input$id_vaccination_type是你要select.

变量的字符串

要实际 select 该变量的值，您可以将变量的名称转换为 symbol 并对其求值，例如使用 bang-bang 运算符 !!。

所以一种解决方案是：

cor(Confirmed_daily, as.numeric(!! sym(input$id_vaccination_type))

我不确定这是否能让您的应用正常运行（我无法在 github 上下载 csv 文件，我更喜欢 dput 作为最小示例），但它应该可以解决这个具体问题。

这个问题还有其他解决方案。一种是使用 get 而不是 !! sym(input))。另一种是使用 varSelectInput，其中 returns 实际名称而不是字符串（所以这里应该不会首先出现问题）。

当从 selectInput 中选择变量时相关性不起作用，但在其他情况下运行得很好

Correlation doesn't work when variable is selected from selectInput but runs perfectly fine otherwise

r

correlation

shiny