nmode's Git Repositories - Rnaught/blob - R/server.R

   1 #' @importFrom methods is
   2 #' @importFrom utils read.csv write.csv
   3 server <- function(input, output) {
   4   reactive <- shiny::reactiveValues(
   5     data_table = data.frame(Name = character(0),
   6                             `Reporting Frequency` = character(0),
   7                             `Case Counts` = numeric(0), check.names = FALSE),
   8     est_table = data.frame(Dataset = character(0)),
   9     estimators = list()
  10   )
  11
  12   # Validate and add datasets when button is clicked.
  13   # Also evaluate the new datasets on existing estimators.
  14   shiny::observeEvent(input$addData, {
  15     # Option 1: Manual entry.
  16     if (input$dataInputMethod == 1) {
  17       checks_passed <- TRUE
  18
  19       # Ensure the dataset name is not blank.
  20       if (grepl("^\\s*$", input$dataName)) {
  21         output$dataNameWarn <- shiny::renderText(
  22           "Error: The dataset name cannot be blank.")
  23         checks_passed <- FALSE
  24       }
  25       # Ensure the dataset name is not a duplicate.
  26       else if (input$dataName %in% reactive$data_table[,1]) {
  27         output$dataNameWarn <- shiny::renderText(
  28           "Error: There is already a dataset with the specified name.")
  29         checks_passed <- FALSE
  30       }
  31       else
  32         output$dataNameWarn <- shiny::renderText("")
  33
  34       # Ensure the case counts consist only of positive integers, separated by
  35       # commas.
  36       counts <- as.numeric(unlist(strsplit(input$dataCounts, split = ",")))
  37       if (any(is.na(counts)) || any(counts <= 0) || any(counts %% 1 != 0)) {
  38         output$dataCountsWarn <- shiny::renderText("Error: The list of case
  39           counts should only contain positive integers, separated by commas.")
  40         checks_passed <- FALSE
  41       }
  42       # Ensure the case counts contain at least two entries.
  43       else if (length(counts) < 2) {
  44         output$dataCountsWarn <- shiny::renderText(
  45           "Error: The list of case counts should contain at least two entries.")
  46         checks_passed <- FALSE
  47       }
  48       else
  49         output$dataCountsWarn <- shiny::renderText("")
  50
  51       if (checks_passed)
  52         d <- data.frame(input$dataName, input$dataUnits, t(counts))
  53     }
  54
  55     else {
  56       checks_passed <- FALSE
  57
  58       # Option 2: Upload .csv
  59       if (input$dataInputMethod == 2)
  60         d <- try(read.csv(input$dataUpload$datapath, header = FALSE))
  61       # Option 3: Paste .csv
  62       else
  63         d <- try(read.csv(text = input$dataPaste, header = FALSE))
  64
  65       if (is(d, "try-error"))
  66         output$dataCSVWarn <- shiny::renderText("Error reading file.")
  67       else if (ncol(d) < 4 || anyNA(d[,1]) || anyNA(sapply(d[,3:4], as.numeric))
  68                || !all(trimws(d[,2]) %in% c("Daily", "Weekly")))
  69         output$dataCSVWarn <- shiny::renderText(
  70           "Error: The provided .csv file does not match the required format.")
  71       else if (length(intersect(reactive$data_table[,1], d[,1])) > 0)
  72         output$dataCSVWarn <- shiny::renderText("Error: The provided .csv file
  73           contains dataset names which already exist.")
  74       else if (length(unique(d[,1])) != length(d[,1]))
  75         output$dataCSVWarn <- shiny::renderText(
  76           "Error: The provided .csv file contains duplicate dataset names.")
  77       else {
  78         output$dataCSVWarn <- shiny::renderText("")
  79         checks_passed <- TRUE
  80       }
  81     }
  82
  83     if (checks_passed) {
  84       d[,3:ncol(d)] <- apply(d[,3:ncol(d)], 2, as.numeric)
  85       d[,3] <- data.frame(I(lapply(split(d[,3:ncol(d)], 1:nrow(d)),
  86                                    function(x) x[!is.na(x)])))
  87       d <- d[,1:3]
  88       d[,2] <- trimws(d[,2])
  89       colnames(d) <- c("Name", "Reporting Frequency", "Case Counts")
  90       reactive$data_table <- rbind(reactive$data_table, d)
  91       reactive$est_table <- update_est_row(input, output, d,
  92         reactive$estimators, reactive$est_table)
  93     }
  94   })
  95
  96   output$dataTable <- shiny::renderDataTable(reactive$data_table,
  97                                              escape = FALSE)
  98   output$estTable <- shiny::renderDataTable(reactive$est_table,
  99                                             escape = FALSE)
 100
 101   # Download table of estimates as a .csv file.
 102   output$downloadEst <- shiny::downloadHandler(
 103     filename = function() { paste0("Rnaught-", Sys.Date(), ".csv") },
 104     content = function(file) { write.csv(reactive$est_table, file) }
 105   )
 106
 107   shiny::observeEvent(input$addWP, {
 108     if (input$serialWPKnown == 1) {
 109       serial <- validate_serial(input, output, "serialWPInput", "serialWPWarn")
 110       if (!is.na(serial)) {
 111         reactive$estimators[[length(reactive$estimators) + 1]] <- list(
 112           method = "WP", mu = serial, mu_units = input$serialWPUnits,
 113           search = list(B = 100, shape.max = 10, scale.max = 10))
 114         reactive$est_table <- update_est_col(input, output, reactive$data_table,
 115           reactive$estimators[[length(reactive$estimators)]],
 116           reactive$est_table)
 117       }
 118     }
 119     else {
 120       checks_passed <- TRUE
 121
 122       grid_length <- as.numeric(input$gridLengthInput)
 123       max_shape <- as.numeric(input$gridShapeInput)
 124       max_scale <- as.numeric(input$gridScaleInput)
 125
 126       if (is.na(grid_length) || grid_length <= 0 || grid_length %% 1 != 0) {
 127         output$gridLengthWarn <- shiny::renderText(
 128           "Error: The grid size must be a positive integer.")
 129         output$gridShapeWarn <- shiny::renderText("")
 130         output$gridScaleWarn <- shiny::renderText("")
 131         checks_passed <- FALSE
 132       }
 133       else {
 134         output$gridLengthWarn <- shiny::renderText("")
 135
 136         if (is.na(max_shape) || max_shape < 1 / grid_length) {
 137           output$gridShapeWarn <- shiny::renderText("Error: The maximum shape
 138             must be at least the reciprocal of the grid length.")
 139           checks_passed <- FALSE
 140         }
 141         else
 142           output$gridShapeWarn <- shiny::renderText("")
 143
 144         if (is.na(max_scale) || max_scale < 1 / grid_length) {
 145           output$gridScaleWarn <- shiny::renderText("Error: The maximum scale
 146             must be at least the reciprocal of the grid length.")
 147           checks_passed <- FALSE
 148         }
 149         else
 150           output$gridScaleWarn <- shiny::renderText("")
 151       }
 152
 153       if (checks_passed) {
 154         reactive$estimators[[length(reactive$estimators) + 1]] <- list(
 155           method = "WP", mu = NA, mu_units = input$serialWPUnits,
 156           search = list(B = grid_length, shape.max = max_shape,
 157                         scale.max = max_scale))
 158         reactive$est_table <- update_est_col(input, output, reactive$data_table,
 159           reactive$estimators[[length(reactive$estimators)]],
 160           reactive$est_table)
 161       }
 162     }
 163   })
 164
 165   shiny::observeEvent(input$addseqB, {
 166     serial <- validate_serial(input, output, "serialseqBInput",
 167                               "serialseqBWarn")
 168     checks_passed <- !is.na(serial)
 169
 170     kappa <- as.numeric(input$kappaInput)
 171     if (is.na(kappa) || kappa <= 0) {
 172       output$kappaWarn <- shiny::renderText(
 173         "Error: The maximum value must be a positive number.")
 174       checks_passed <- FALSE
 175     }
 176     else
 177       output$kappaWarn <- shiny::renderText("")
 178
 179     if (checks_passed) {
 180       reactive$estimators[[length(reactive$estimators) + 1]] <- list(
 181         method="seqB", mu = serial, kappa = kappa,
 182         mu_units = input$serialseqBUnits)
 183       reactive$est_table <- update_est_col(input, output, reactive$data_table,
 184         reactive$estimators[[length(reactive$estimators)]], reactive$est_table)
 185     }
 186   })
 187
 188   shiny::observeEvent(input$addID, {
 189     serial <- validate_serial(input, output, "serialIDInput", "serialIDWarn")
 190     if (!is.na(serial)) {
 191       reactive$estimators[[length(reactive$estimators) + 1]] <- list(
 192         method = "ID", mu = serial, mu_units = input$serialIDUnits)
 193       reactive$est_table <- update_est_col(input, output, reactive$data_table,
 194         reactive$estimators[[length(reactive$estimators)]], reactive$est_table)
 195     }
 196   })
 197
 198   shiny::observeEvent(input$addIDEA, {
 199     serial <- validate_serial(input, output, "serialIDEAInput",
 200                               "serialIDEAWarn")
 201     if (!is.na(serial)) {
 202       reactive$estimators[[length(reactive$estimators) + 1]] <- list(
 203         method = "IDEA", mu = serial, mu_units = input$serialIDEAUnits)
 204       reactive$est_table <- update_est_col(input, output, reactive$data_table,
 205         reactive$estimators[[length(reactive$estimators)]], reactive$est_table)
 206     }
 207   })
 208 }
 209
 210 validate_serial <- function(input, output, serialInputId, serialWarnId) {
 211   serial <- as.numeric(input[[serialInputId]])
 212   if (is.na(serial) || serial <= 0) {
 213     output[[serialWarnId]] <- shiny::renderText(
 214       "Error: The mean serial interval should be a positive number.")
 215     serial <- NA
 216   }
 217   else
 218     output[[serialWarnId]] <- shiny::renderText("") # Clear warning text.
 219
 220   return(serial)
 221 }
 222
 223 # Create a new column in the estimator table when a new estimator is added.
 224 update_est_col <- function(input, output, datasets, estimator, est_table) {
 225   if (nrow(datasets) == 0)
 226     new_est_table <- data.frame(matrix(nrow = 0, ncol = ncol(est_table) + 1))
 227   else {
 228     estimates <- rep(NA, nrow(datasets))
 229
 230     for (row in 1:nrow(datasets))
 231       estimates[row] <- eval_estimator(input, output, estimator, datasets[row,])
 232
 233       if (nrow(est_table) == 0)
 234         new_est_table <- cbind(datasets[,1], estimates)
 235       else
 236         new_est_table <- cbind(est_table, estimates)
 237   }
 238
 239   colnames(new_est_table) <- c(colnames(est_table), shiny::HTML(
 240     paste0(estimator$method, "<br/>(&mu; = ", estimator$mu, " ",
 241            tolower(estimator$mu_units), ")")))
 242
 243   return(new_est_table)
 244 }
 245
 246 # Create a new row in the estimator table when new datasets are added.
 247 update_est_row <- function(input, output, datasets, estimators, est_table) {
 248   if (length(estimators) == 0) {
 249     if (nrow(est_table) == 0)
 250       new_est_table <- data.frame(datasets[,1])
 251     else
 252       new_est_table <- data.frame(c(est_table[,1], datasets[,1]))
 253
 254     colnames(new_est_table) <- colnames(est_table)
 255   }
 256   else {
 257     new_est_table <- data.frame(matrix(nrow = nrow(datasets),
 258                                        ncol = length(estimators)))
 259
 260     for (row in 1:nrow(datasets))
 261       for (col in 1:length(estimators))
 262         new_est_table[row, col] <- eval_estimator(input, output,
 263           estimators[[col]], datasets[row,])
 264
 265     new_est_table <- cbind(datasets[,1], new_est_table)
 266     colnames(new_est_table) <- colnames(est_table)
 267     new_est_table <- rbind(est_table, new_est_table)
 268   }
 269
 270   return(new_est_table)
 271 }
 272
 273 # Evaluate an estimator on a given dataset.
 274 eval_estimator <- function(input, output, estimator, dataset) {
 275   # Adjust serial interval to match time unit of case counts.
 276   serial <- estimator$mu
 277   if (estimator$mu_units == "Days" && dataset[2] == "Weekly")
 278     serial <- serial / 7
 279   else if (estimator$mu_units == "Weeks" && dataset[2] == "Daily")
 280     serial <- serial * 7
 281
 282   # White and Panago
 283   if (estimator$method == "WP") {
 284     estimate <- WP(unlist(dataset[3]), mu = serial, search = estimator$search)
 285
 286     if (!is.na(estimator$mu))
 287       estimate <- round(estimate$Rhat, 2)
 288     # Display the estimated mean of the serial distribution if mu was not
 289     # specified.
 290     else {
 291       if (dataset[2] == "Daily")
 292         mu_units <- "days"
 293       else
 294         mu_units <- "weeks"
 295       MSI <- sum(estimate$SD$supp * estimate$SD$pmf)
 296       estimate <- shiny::HTML(paste0(round(estimate$Rhat, 2), "<br/>(&mu; = ",
 297                                      round(MSI, 2), " ", mu_units, ")"))
 298     }
 299   }
 300   # Sequential Bayes
 301   else if (estimator$method == "seqB")
 302     estimate <- round(seq_bayes(unlist(dataset[3]), mu = serial,
 303                            kappa = estimator$kappa), 2)
 304   # Incidence Decay
 305   else if (estimator$method == "ID")
 306     estimate <- round(id(unlist(dataset[3]), mu = serial), 2)
 307   # Incidence Decay with Exponential Adjustement
 308   else if (estimator$method == "IDEA")
 309     estimate <- round(idea(unlist(dataset[3]), mu = serial), 2)
 310
 311   return(estimate)
 312 }