inst/flowfinder/high_flows_tab.R

In mikejohnson51/FlowlineFinder: Find, Vizualize and Download NWM and NHD Data in 'Shiny'

# Generate Dygraph
dygraph_flood <- function(comid, data, number, normals) {
  
  colors = c("orange", "green", "red", "purple",
             "lightblue", "lightgreen", "pink", "lightred", "gray",
             "darkblue", "darkred", "darkgreen", "darkpurple")
  
  # Get data for new comid
  subset = subset_nomads(comids = comid)
  
  # First time creating a data frame
  if (is.null(data)){
    df <- data.frame(subset$Q_cfs)
    colnames(df) <- comid
    df = xts::xts(df, order.by = subset$dateTime)
  } else {
    df = data
    prev_names = colnames(df)
    df$new_id <- subset$Q_cfs
    colnames(df) <- c(prev_names, comid)
  }
  
  graph = dygraphs::dygraph(df) %>%
    dyOptions(colors = colors,
              drawPoints = TRUE, 
              pointSize = 2,
              gridLineColor = "#7f7f7f",
              axisLineColor = "#b2b2b2") %>% 
    dyCSS("www/dygraph.css") %>%
    dyAxis("x", drawGrid = FALSE) %>%
    dyHighlight(highlightCircleSize = 5,
                highlightSeriesBackgroundAlpha = 1) %>%
    dyAxis("y", label = "Streamflow (cfs)" )%>%
    dyLegend(show = "onmouseover")
  
  
  
  if (ncol(df) == 1) {
    
    #cutoff = norm[norm$COMID == comid,][[2]]
    
    cutoff <- normals %>% 
      filter(COMID == comid)
    
    cutoff = cutoff[,2] * 35.3147
    
    mn = mean(df[[2]], na.rm = TRUE)
    std = sd(df[[2]], na.rm = TRUE)
    
    graph = graph %>%
      dyOptions(
        colors = colors,
        drawPoints = TRUE, 
        pointSize = 2,
        gridLineColor = "#7f7f7f",
        axisLineColor = "#b2b2b2",
        fillGraph = TRUE, 
        fillAlpha = 0.1
      )  %>%
      dyLimit(cutoff, 
              strokePattern = "solid", 
              color = "red", 
              label = paste0("Monthly Average (", round(cutoff,2), " cfs)")) %>%
      dyShading(from = mn - std, 
                to = mn + std, 
                axis = "y")
  }
  
  return(list(graph = graph,
              data_set = df))
}