我想在Shiny内部下载一个地理参考PDF文件(geoPDF(，为此需要一些步骤，如将ggplot格式的绘图转换为tiff，填充空间坐标，创建地理tiff，最后是我的geoPDF。但是tempdir()目录中downloadHandler()函数的几个步骤总是导致错误：
Listening on http://127.0.0.1:6096
Checking gdal_installation...
GDAL version 3.1.4
GDAL command being used: "C:OSGeo4W64bingdal_translate.exe" -ot "Byte" -of "PDF" -a_srs "+proj=longlat +ellps=GRS80 +towgs84=0,0,0 +no_defs" -co "TILED=YES" "CERROCOROADO001G.tif" "C:UsersforesAppDataLocalTempRtmpiQIcHSfile1117c7099730a.pdf"
Warning in system(cmd, intern = TRUE) :
execução do comando '"C:OSGeo4W64bingdal_translate.exe" -ot "Byte" -of "PDF" -a_srs "+proj=longlat +ellps=GRS80 +towgs84=0,0,0 +no_defs" -co "TILED=YES" "CERROCOROADO001G.tif" "C:UsersforesAppDataLocalTempRtmpiQIcHSfile1117c7099730a.pdf"' teve status 1
ERROR 4: CERROCOROADO001G.tif: No such file or directory
我的代码是：
# Packages
require(rgdal)
require(shiny)
require(ggplot2)
require(ggpubr)
require(dplyr)
require(shinythemes)
require(ggspatial)
require(sf)
require(maptools)
require(lubridate)
# get AOI
download.file(
"https://github.com/Leprechault/trash/raw/main/stands_example.zip",
zip_path <- tempfile(fileext = ".zip")
)
unzip(zip_path, exdir = tempdir())
# Open the files
setwd(tempdir())
stands_extent <- readOGR(".", "stands_target") # Border
stands_ds <- read.csv("pred_target_stands.csv", sep=";") # Data set
stands_ds <- stands_ds %>%
mutate(DATA_S2 = ymd(DATA_S2))
# Create the shiny dash
ui <- fluidPage(
theme = shinytheme("cosmo"),
titlePanel(title="My Map Dashboard"),
sidebarLayout(
sidebarPanel(
selectInput(inputId = "selectedvariable0",
label = "Type",
choices = c(unique(stands_ds$PEST)),selected = TRUE ),
selectInput(inputId = "selectedvariable1",
label = "Date",
choices = c(unique(stands_ds$DATA_S)),uiOutput("selectedvariable0")),
selectInput(inputId = "selectedvariable2",
label = "Project",
choices = c(unique(stands_ds$PROJETO)),uiOutput("selectedvariable1")),
selectInput(inputId = "selectedvariable3",
label = "Stand",
choices = c(unique(stands_ds$CD_TALHAO)),selected = TRUE),
selectInput(inputId = "selectedvariable4",
label = "Unique ID",
choices = c(unique(stands_ds$ID_UNIQUE)),selected = TRUE),
downloadButton("download1", "Save as *geoPDF")
),
mainPanel(
textOutput("idSaida"),
fluidRow(
splitLayout(plotOutput("myplot"))),
dateInput(inputId = "Dates selection", label = "Time")
)
)
)
server <- function(input, output){
currentvariable0 <- reactive({input$selectedvariable0})
currentvariable1 <- reactive({input$selectedvariable1})
currentvariable2 <- reactive({input$selectedvariable2})
currentvariable3 <- reactive({input$selectedvariable3})
currentvariable4 <- reactive({input$selectedvariable4})
output$myplot <- renderPlot({
#Subset stand
stands_sel <- subset(stands_extent, stands_extent@data$ID_UNIQUE==currentvariable4())
#Subset for input$var and assign this subset to new object, "fbar"
ds_sel<- stands_ds[stands_ds$ID_UNIQUE==currentvariable4(),]
#Create a map
polys <- st_as_sf(stands_sel)
ggplot() +
geom_sf(data=polys) +
geom_point(data=ds_sel,
aes(x=X, y=Y), color="red") +
xlab("Longitude") + ylab("Latitude") +
coord_sf() +
theme_bw() +
theme(text = element_text(size=10))
})
MyPlot <- reactive({
#Subset stand
stands_sel <- subset(stands, stands@data$UNIQUE==currentvariable4())
#Subset data set
stands_actual<-pred_attack[pred_attack$ID_UNIQUE==currentvariable4(),]
#Create a map
polys <- st_as_sf(stands_sel)
ggplot() +
ggtitle(currentvariable4()) +
geom_sf(data=polys) +
geom_point(data=stands_actual,
aes(x=x, y=y), color="red") +
ggspatial::annotation_north_arrow(location = "bl", which_north = "true",
pad_x = unit(0.3, "in"), pad_y = unit(0.5, "in"),
style = north_arrow_fancy_orienteering) + #Add a north arrow
ggspatial::annotation_scale(location = "bl", width_hint = 0.55) + #Add a scale bar
xlab("Longitude") + ylab("Latitude") +
coord_sf() +
theme_bw() +
theme(text = element_text(size=10))
# Save the plot
ggsave(MyPlot(), gsub("[[:punct:]]", "", iconv(currentvariable4(), from = '', to = 'ASCII//TRANSLIT')),device = "tiff")
# Create a StackedRaster object from the saved plot
stackedRaster <- stack(paste0(gsub("[[:punct:]]", "", iconv(currentvariable4(), from = '', to = 'ASCII//TRANSLIT')),".tiff"))
# Get the GeoSpatial Components
lat_long <- ggplot_build(MyPlot())$layout$panel_params[[1]][c("x_range","y_range")]
# Supply GeoSpatial data to the StackedRaster
extent(stackedRaster) <- c(lat_long$x_range,lat_long$y_range)
projection(stackedRaster) <- CRS("+proj=longlat +ellps=GRS80 +towgs84=0,0,0 +no_defs")
# Create the GeoTiff
writeRaster(stackedRaster, paste0(gsub("[[:punct:]]", "", iconv(currentvariable4(), from = '', to = 'ASCII//TRANSLIT')),".tif",sep=""), options="PHOTOMETRIC=RGB", datatype="INT1U",overwrite=TRUE)
})
output$myplot3 <- renderPlot(MyPlot())
output$download1 <- downloadHandler(
filename = function() {
paste0(currentvariable4(),"-",Sys.Date(),".pdf",sep="")
},
content = function(file) {
#Save map as GeoPDF
open.file<-paste0(gsub("[[:punct:]]", "", iconv(currentvariable4(), from = '', to = 'ASCII//TRANSLIT')),".tif", sep="")
gdalUtils::gdal_translate(open.file, file, of="PDF", ot="Byte",
co="TILED=YES",verbose=TRUE, overwrite=T, a_srs="+proj=longlat +ellps=GRS80 +towgs84=0,0,0 +no_defs")
}
)
}
shinyApp(ui, server)
##
有人能帮我吗？
提前谢谢。
您不能执行output$myplot()。这就是您所得到的错误的来源。如果你想得到绘图，在无功导体中生成：
MyPlot <- reactive({
# code which generates the ggplot
})
然后进行
output$myplot <- renderPlot(MyPlot())
在CCD_ 4中，您可以通过调用CCD_。
在downloadHandler的content函数中，要保存的文件必须是content函数的参数file。save.file <- file也是如此。
我注意到的一件事是，下载处理程序中没有file的输出。也许你的线路：
#Save map as GeoPDF
open.file<-paste0(tempdir(),currentvariable4(),".tif", sep="")
save.file<-paste0(tempdir(),currentvariable4(),".pdf", sep="")
gdalUtils::gdal_translate(open.file,save.file,of="PDF", ot="Byte",
co="TILED=YES",verbose=TRUE, overwrite=T, a_srs="+proj=longlat +ellps=GRS80 +towgs84=0,0,0 +no_defs")
实际上应该是
#Save map as GeoPDF
open.file<-paste0(tempdir(),currentvariable4(),".tif", sep="")
gdalUtils::gdal_translate(open.file, file, of="PDF", ot="Byte",
co="TILED=YES",verbose=TRUE, overwrite=T, a_srs="+proj=longlat +ellps=GRS80 +towgs84=0,0,0 +no_defs")
我也不确定您是否需要使用tempdir()。无论如何，所有内容都会构建在会话的临时目录中。