极简主义shiny app

转载自：http://site.douban.com/182577/widget/notes/10568279/note/349413814/

为了上课，赶制了一个异常简单的shiny app。展示二项树期权的定价。
贴在这里，立此存照。等着以后有时间慢慢把它做漂亮。。。

1.二项树期权

用fOptions包的BinomialTreeOption（）计算期权价格；用BinomialTreePlot（）展示期权价格二项树。

2.shiny

# ui.R
library(shiny)
shinyUI(pageWithSidebar(
headerPanel("Option types and Parameters"),
sidebarPanel(
 selectInput(inputId = "comboBox",
label = "TypeFlag",choices = list(" European call option" = "ce", "European put option" = "pe", "American call option" = "ca","American put option" = "pa")),
  
  numericInput(inputId = "pickNumber",
label = "Time",
min = 0, max = 10, value = 1),
numericInput(inputId = "pickNumber",
label = "Sigma",
min = 0, max = 1, value = .1),
numericInput(inputId = "pickNumber",
label = "r",
min = 0, max = 1, value = .1),
numericInput(inputId = "pickNumber",
label = "S",
min = 0, max = 10000, value = 1),
numericInput(inputId = "pickNumber",
label = "X",
min = 0, max = 10000, value = 1),

sliderInput(inputId = "slider",
label = "n",
min = 1, max = 10, value = 2, step = 1),
),
mainPanel(
h3("CRR Binomial Tree Option"),
plotOutput("plotDisplay")
)
))


#server.r
library(shiny)
library(fOptions)

shinyServer(function(input, output) {
  output$plotDisplay <- renderPlot({
    crr<-BinomialTreeOption(TypeFlag = input$comboBox,S=input$pickNumber4, X=input$pickNumber5, 
                       Time=input$pickNumber1, r=input$pickNumber3, b=0, sigma=input$pickNumber2,
                       n=input$slider)
    print(BinomialTreePlot(crr, dx = 0.05, dy = 0.2,
                           cex = 1, digits = 2,ylim=c(-input$slider-1,input$slider+1)))
    
  })
})

把ui.r和serve.r各自保存为文件，放入同一个文件夹中/rresult。设置路径:
setwd('~/rresult')
运行：
runApp()

就可以看到所作的shiny应用了。