UseMethod（"filter_"）错误：使用 R 访问和处理 Quikscat 风速和风向时

Question

我计划按照 link 中显示的教程使用 Quickscat 数据绘制风速和风向：Access and Process Quikscat Wind speed and direction with R。

代码的所有小节似乎都可以正常工作。但在 风场操纵 部分，特别是通过使用 filter() 函数定义地理边界来为感兴趣的区域选择数据；执行返回 Error in UseMethod("filter_") : no applicable method for 'filter_' applied to an object of class "NULL"。 screenshot of the error

我假设他们正在选择数据中不存在的地理区域。虽然我不确定。获得正确的坐标是否可以解决问题？有什么建议我该怎么办？此外，如果您有从 netCDF 文件或任何其他文件绘制风数据的替代代码，如果您与我分享这些代码，我将不胜感激。谢谢。

Answer 1

当我运行教程中的代码时，他们在 tidyverse 中使用了折旧函数 as.tibble() 并抛出了错误。我通过屏幕截图中的行将其更改为 as_tibble() 和运行其余代码，没有任何错误。在尝试过滤之前，您是否查看了 velocity.all 数据框？如果由于 tibble 错误而导致 NULL 值可能是您的问题。

require(xtractomatic)
require(tidyverse)
require(oce)
require(lubridate)
require(gganimate)
require(sf)

getInfo("qsux101day")
getInfo("qsuy101day")

# set spatial extent
lon = c(25,65)
lat =  c(-35,10)
## set temporal extent
time = c("2006-01-01", "2006-12-31")

wind_x = xtracto_3D(dtype = "qsux101day", 
                    xpos = lon, 
                    ypos = lat, 
                    tpos = time)

wind_y = xtracto_3D(dtype = "qsuy101day", 
                    xpos = lon, 
                    ypos = lat, 
                    tpos = time)

## extract location and time bounds as vector
longitude = wind_x$longitude
latitude = wind_x$latitude
time = wind_x$time%>%as.Date()

## extract u and v as array
# eastward velocity (zonal)
u = wind_x$data
# northward velocity (meridional)
v = wind_y$data

# calculate wind velocity
velocity = sqrt(u^2 + v^2)


n.lon = length(longitude)
n.lat = length(latitude)+1


velocity.all = NULL

for (i in 1:length(time)){
  velocity.df = data.frame(longitude, velocity[,,i] %>% as.data.frame()) %>% 
    gather(key = "key" , value = "velocity", 2:n.lat) %>% 
    mutate(latitude = rep(latitude, each = n.lon), date = time[i]) %>% 
    select(date,longitude, latitude, velocity)%>% 
    as_tibble()

  velocity.all = velocity.all %>% bind_rows(velocity.df)
}

velocity.month = velocity.all %>% 
  filter(between(longitude,38,55)) %>% 
  filter(between(latitude,-15,-7)) %>% 
  mutate(day = yday(date) %>% as.integer(), week = week(date)%>% as.integer(), 
         month = month(date)%>% as.integer())%>%
  group_by(longitude, latitude, month) %>%
  summarise(velocity = mean(velocity, na.rm = TRUE))

UseMethod（"filter_"）错误：使用 R 访问和处理 Quikscat 风速和风向时

Error in UseMethod("filter_"): while Accessing and Processing Quikscat Wind speed and direction with R

r

plot

filter

netcdf

atmosphere