R/plot_error.R

In mengluchu/APMtools: statistical air pollution mapping tools

#' Plot the prediction errors in space
#' @param validataion The validataion vector
#' @param prediction The prediction vector
#' @param err The error vector, if provided, the 'validataion' and 'prediction' are not needed.
#' @param geome geometry of an sf
#' @param extremequantil_low the low quantile to filter out for better visualization
#' @param extremequantil_high the high quantile to filter out for better visualization
#' @return a plot of prediction error distributed in space
#' @export


plot_error = function(validation = 0, prediction = 0, geome, err = NA, extremequantil_low = 0.025, extremequantil_high = 0.975, plotraster = T) {
    colorB = brewer.pal(7, "Greens")
    colorG = brewer.pal(11, "PiYG")
    colorS = brewer.pal(11, "Spectral")
    spatialerr = function(validation = 0, prediction = 0, err = err, geome, extremequantil_low, extremequantil_high) {
        if (is.na(err)) 
            err = prediction - validation
        
        
        IDX = which(err > quantile(err, extremequantil_low) & err < quantile(err, extremequantil_high))
        
        err = err[IDX]
        geome = geome[IDX]
        sf1 = st_sf(err, geome)
        
        names(sf1) = c("error", "geometry")
        st_geometry(sf1) <- "geometry"
        return(sf1)
        
    }
    
    
    if (!is.na(err)) {
        sf1 = spatialerr(validation = validation, err = err, prediction = prediction, geome = geome, extremequantil_low = extremequantil_low, extremequantil_high = extremequantil_high)
        
        if (plotraster == F) 
            ggplot(sf1) + geom_sf(aes(color = error)) + scale_colour_gradientn(colours = colorG) + labs(title = "validation error") else {
            e <- extent(sf1)
            r <- raster(e, resolution = 0.5)
            x <- rasterize(sf1, r, fun = mean)
            rasterVis::levelplot(x[[2]], margin = F)
        }
    } else {
        sf1 = spatialerr(err = err, geome = geome, extremequantil_low = extremequantil_low, extremequantil_high = extremequantil_high)
        if (plotraster == F) 
            ggplot() + geom_sf(data = sf1, aes(color = error)) + scale_colour_gradientn(colours = colorS) + labs(title = "residuals") + layer(sp.polygons(Germany)) else {
            e <- extent(sf1)
            r <- raster(e, resolution = 0.5)
            x <- rasterize(sf1, r, fun = mean)
            rasterVis::levelplot(x[[2]], margin = F)
        }
        
    }
}