我試圖開發一個簡單的應用程序,用於預測在給定某個年齡,班級,票價等的情況下乘客倖存泰坦尼克號的概率。我希望這些變量是動態的,並且希望使用底層脫字符模型計算預測的生存概率。插入符號和閃亮符號:無法創建由插入符號模式驅動的預測應用程序
當運行這段代碼,我收到以下錯誤信息:
Warning: Error in [.data.frame: undefined columns selected Stack trace (innermost first): 70: [.data.frame 69: [ 68: sweep 67: predict.preProcess 66: predict 65: probFunction 64: predict.train 63: predict 62: predict 61: is.data.frame 60: data.matrix 59: observerFunc [#17] 4: 3: do.call 2: print.shiny.appobj 1: ERROR: [on_request_read] connection reset by peer
我的代碼如下。任何想法是什麼導致這個錯誤?非常感謝。
require(shiny)
require(plyr)
require(dplyr)
require(ggplot2)
require(caret)
require(xgboost)
require(titanic)
df=na.omit(titanic_train)
y=data.matrix(select(df, Survived))
y[y==0]="N"
y[y==1]="Y"
x=data.matrix(select(df, Pclass, Age, SibSp, Parch, Fare))
tCtrl <- trainControl(method = "repeatedcv", number = 3, repeats=3, summaryFunction = twoClassSummary, verbose=TRUE, classProbs = TRUE)
fit_xgbTree= train(x, y, method = "xgbTree" , family= "binomial", trControl = tCtrl, metric = "ROC", preProc = c("center", "scale"))
ui = pageWithSidebar(
headerPanel("Titanic"),
sidebarPanel(
radioButtons("Pclass", "Passenger Class", choices=c("1", "2", "3"),selected = "1", inline = TRUE,width = NULL),
sliderInput("Age", "Passenger Age", min=0, max=80, value=30),
radioButtons("SibSp", "SibSp", choices=c("0", "1", "2", "3", "4", "5")),
radioButtons("Parch", "Parch", choices=c("0", "1", "2", "3", "4", "5", "6")),
sliderInput("Fare", "Passenger Fare", min=0, max=520, value=35)
),
mainPanel(
dataTableOutput('testTable'),
textOutput('outputBox')
)
)
server=function(input, output){
values <- reactiveValues()
newEntry <- observe({ # use observe pattern
x=as.data.frame(matrix(0, nrow=1, ncol=5))
colnames(x)=c("Pclass", "Age", "SibSp", "Parch", "Fare")
x[1,1]=as.numeric(input$Pclass)
x[1,2]=input$Age
x[1,3]=as.numeric(input$SibSp)
x[1,4]=as.numeric(input$Parch)
x[1,5]=input$Fare
pred <- data.matrix(predict(object=fit_xgbTree, x, type="prob")[,2])
isolate(values$df <- x)
#isolate(values$df2 <- x)
})
output$testTable <- renderDataTable({values$df})
}
shinyApp(ui=ui, server=server)
我相信它可能有是由NA導致的...在'x [1,1] = as.numeric(輸入$ Pclass)'中,由於輸入$ PClass是選擇「1st」,「2nd」,「3rd」,所以通過運行'as.numeric'來獲得NAs。預測功能失敗。所以你不會得到預測函數返回的矩陣,也不能運行'[,2]'。 – Jean
Pclass是數字。你可以通過運行唯一的(df $ Pclass) – user3725021
'input $ Pclass'來檢查這個字符。 – Jean