Merge branch 'issue-3' into develop

* issue-3:
  Title case for title
  Diagnosis as radio buttons (#4)
  Output as table (#4)
  Added calculation of HR for Fontan (#3)
  Simplified variable names
  Added calculation of HR for moderate (#3)
  Changed placeholders to NA (#3)
  Added calculation of heart rate for simple defects (#3)

src/server.R

@@ -1,52 +1,52 @@
 server <- function(input, output) {
-  # Calculate endpoints
-  output$vo2_ml_min <- renderText({
-    vo2_ml_min()
-  })
-  output$vo2_ml_kg_min <- renderText({
-    vo2_ml_kg_min()
-  })
-  output$heart_rate <- renderText({
-    heart_rate()
-  })
-  output$ventilation <- renderText({
-    ventilation()
-  })
-  output$oxygen_pulse <- renderText({
-    oxygen_pulse()
-  })
-  output$ve_vco2_slope <- renderText({
-    ve_vco2_slope()
-  })
-  output$breathing_frequency <- renderText({
-    breathing_frequency()
-  })
-
   vo2_ml_min <- function() {
-    1
+    NA
   }
 
   vo2_ml_kg_min <- function() {
-    2
+    NA
   }
 
-  heart_rate <- function() {
-    3
+  heart_rate <- function(diagnosis, height, bmi, sex) {
+    software <- 0.0469 # prop. of Vyntus on Fontan (only relevant case here)
+    switch(diagnosis,
+      simple = (9168804 * height + 5.13e9) ^ (1 / 4.3),
+      moderate = (9.9e8 * height - 2.86e9 * bmi + 1.4e11) ^ (1 / 5),
+      fontan = (-144400.5 * height - 3.81e7 * sex + 2076971 * bmi * sex + 1.24e7 * software + 9.75e7) ^ (1 / 3.5)
+    )
   }
 
   ventilation <- function() {
-    4
+    NA
   }
 
   oxygen_pulse <- function() {
-    5
+    NA
   }
 
   ve_vco2_slope <- function() {
-    6
+    NA
   }
 
   breathing_frequency <- function() {
-    7
+    NA
   }
+
+  output$results_table <- renderTable({
+    data.frame(
+      "Metric" = c(
+        "VO2 ml/min", "VO2 ml/kg/min", "Heart rate", "Ventilation",
+        "Oxygen pulse", "VE/VCO2 slope", "Breathing frequency"
+      ),
+      "Value" = c(
+        vo2_ml_min(),
+        vo2_ml_kg_min(),
+        heart_rate(input$diagnosis, input$height, input$bmi, as.numeric(input$sex)),
+        ventilation(),
+        oxygen_pulse(),
+        ve_vco2_slope(),
+        breathing_frequency()
+      )
+    )
+  })
 }

src/ui.R

@@ -1,16 +1,16 @@
 ui <- fluidPage(
   # Step 1: selecting diagnosis
-  h1("Kids with congenital heart defects"),
+  h1("Kids with Congenital Heart Defects"),
   wellPanel(
     h2("Select diagnosis"),
-    selectInput(
-      inputId = "diagnosis",
-      label   = "Diagnostic group:",
-      choices = c(
-        "Simple defects" = "simple_defects",
-        "Moderate complex defects" = "moderate_complex_defects",
-        "Fontan circulation" = "fontan_circulation"
-      )
+    radioButtons(
+      "diagnosis", "Diagnostic group:",
+      choiceNames = c(
+        "Simple defects",
+        "Moderate complex defects",
+        "Univentricular defects with Fontan circulation"
+      ),
+      choiceValues = c("simple", "moderate", "fontan")
     ),
     # Add "Next" button
     actionButton("next", "Next")
@@ -20,7 +20,11 @@ ui <- fluidPage(
     condition = "input.next > 0",
     wellPanel(
       h2("Select covariates"),
-      radioButtons("sex", "Sex", c("Male", "Female")),
+      radioButtons(
+        "sex", "Sex",
+        selected = character(0),
+        choiceNames = list("Male", "Female"), choiceValues = list(1L, 0L)
+      ),
       numericInput(
         "height", "Height (cm)",
         value = 100L, min = 0L, step = 1L, max = 200L
@@ -37,13 +41,7 @@ ui <- fluidPage(
     condition = "input.submit > 0",
     wellPanel(
       h2("Results"),
-      "VO2 ml/min: ", textOutput("vo2_ml_min"),
-      "VO2 ml/kg/min: ", textOutput("vo2_ml_kg_min"),
-      "Heart rate: ", textOutput("heart_rate"),
-      "Ventilation: ", textOutput("ventilation"),
-      "Oxygen pulse: ", textOutput("oxygen_pulse"),
-      "VE/VCO2 slope: ", textOutput("ve_vco2_slope"),
-      "Breathing frequency: ", textOutput("breathing_frequency")
+      tableOutput("results_table")
     )
   )
 )