从多个 hdf 文件中提取一个变量

Question

我有这 3 个文件 here。尝试堆叠它们并提取一个名为“OzoneTropColumn”的变量。我能够为单个文件提取数据，但无法为多个文件提取数据。

library(raster)
library(ncdf4)
list_col1 <- list.files("E:/TES", pattern = "*.hdf", full.names = TRUE) 
ncin1 <- raster::stack(list_col1, varname = "Data Fields/OzoneTropColumn", ncdf=TRUE)

如有任何帮助，我们将不胜感激。

谢谢

Answer 1

我不知道这是否真的有效，因为我不是 raster 或导入 hdf 文件方面的专家。但是这段代码确实为我加载了 R 中的三个文件，但仍然给出了一些警告：-

library(raster)
library(ncdf4)
list_col1 <- as.list(list.files("E:/TES", pattern = "*.hdf",
                                full.names = TRUE))
ncin1 <- raster::stack(list_col1,
                       varname = "Data Fields/OzoneTropColumn",
                       ncdf=TRUE)

[1] "vobjtovarid4: **** WARNING **** I was asked to get a varid for dimension named Data Fields/phony_dim_1 BUT this dimension HAS NO DIMVAR! Code will probably fail at this point"
[1] "vobjtovarid4: **** WARNING **** I was asked to get a varid for dimension named Data Fields/phony_dim_0 BUT this dimension HAS NO DIMVAR! Code will probably fail at this point"
[1] "vobjtovarid4: **** WARNING **** I was asked to get a varid for dimension named Data Fields/phony_dim_1 BUT this dimension HAS NO DIMVAR! Code will probably fail at this point"
[1] "vobjtovarid4: **** WARNING **** I was asked to get a varid for dimension named Data Fields/phony_dim_0 BUT this dimension HAS NO DIMVAR! Code will probably fail at this point"
[1] "vobjtovarid4: **** WARNING **** I was asked to get a varid for dimension named Data Fields/phony_dim_1 BUT this dimension HAS NO DIMVAR! Code will probably fail at this point"
[1] "vobjtovarid4: **** WARNING **** I was asked to get a varid for dimension named Data Fields/phony_dim_0 BUT this dimension HAS NO DIMVAR! Code will probably fail at this point"
[1] "vobjtovarid4: **** WARNING **** I was asked to get a varid for dimension named Data Fields/phony_dim_1 BUT this dimension HAS NO DIMVAR! Code will probably fail at this point"
[1] "vobjtovarid4: **** WARNING **** I was asked to get a varid for dimension named Data Fields/phony_dim_0 BUT this dimension HAS NO DIMVAR! Code will probably fail at this point"

但确实显示它已读取 3 个文件

ncin1[[1]]
class      : RasterLayer 
dimensions : 83, 90, 7470  (nrow, ncol, ncell)
resolution : 1, 1  (x, y)
extent     : 0.5, 90.5, 0.5, 83.5  (xmin, xmax, ymin, ymax)
crs        : NA 
source     : /home/shawn/Downloads/TES/TES-Aura_L3-O3-M2004m09_F01_12.hdf 
names      : Data.Fields.OzoneTropColumn.1 
zvar       : Data Fields/OzoneTropColumn

ncin1[[2]]
class      : RasterLayer 
dimensions : 83, 90, 7470  (nrow, ncol, ncell)
resolution : 1, 1  (x, y)
extent     : 0.5, 90.5, 0.5, 83.5  (xmin, xmax, ymin, ymax)
crs        : NA 
source     : /home/shawn/Downloads/TES/TES-Aura_L3-O3-M2004m10_F01_12.hdf 
names      : Data.Fields.OzoneTropColumn.2 
zvar       : Data Fields/OzoneTropColumn

ncin1[[3]]
class      : RasterLayer 
dimensions : 83, 90, 7470  (nrow, ncol, ncell)
resolution : 1, 1  (x, y)
extent     : 0.5, 90.5, 0.5, 83.5  (xmin, xmax, ymin, ymax)
crs        : NA 
source     : /home/shawn/Downloads/TES/TES-Aura_L3-O3-M2004m11_F01_12.hdf 
names      : Data.Fields.OzoneTropColumn.3 
zvar       : Data Fields/OzoneTropColumn

Answer 2

Robert 发布的脚本运行良好，唯一的区别是使用 as.list 和不使用 as.list]1]1. I tried before using without as.list. The extracted data loses its georeference for reason unknown. So had to give extent and projection after raster stack. Thanks Robert.

从多个 hdf 文件中提取一个变量

Extracting a variable from multiple hdf files

r

hdfs

raster

netcdf

hdf