sits (version 0.13.0)

sits_get_data: Obtain time series from different sources

Description

Retrieve a set of time series from a data cube or from a time series service. Data cubes and puts it in a "sits tibble". Sits tibbles are the main structures of sits package. They contain both the satellite image time series and their metadata. A sits tibble is a tibble with pre-defined columns that has the metadata and data for each time series. The columns are <longitude, latitude, start_date, end_date, label, cube, time_series>. There are many ways of retrieving time series:

• SATVEG:Retrieve data from SATVEG service using a lat/long point (see S3 method for class 'satveg_cube'), a CSV file (see S3 method for class 'csv_satveg_cube') or a SHP file (see S3 method for class 'shp_satveg_cube')

• RASTER: Retrieve data from any raster cube using a lat/long point (see S3 method for class 'raster_cube'), a CSV file (see S3 method for class 'csv_raster_cube') or a SHP file (see S3 method for class 'shp_raster_cube')

The URL and other parameters for accessing the time series services are defined in the package configuration file. This file is "config.yml". Please see the sits_config for more information.

Before using this service, the user should create a valid description of a data cube using the sits_cube function.

Usage

sits_get_data(cube, file = NULL, ..., multicores = 1)
# S3 method for wtss_cube
sits_get_data(
  cube,
  file = NULL,
  ...,
  longitude = NULL,
  latitude = NULL,
  start_date = NULL,
  end_date = NULL,
  bands = NULL,
  label = "NoClass"
)
# S3 method for satveg_cube
sits_get_data(
  cube,
  file = NULL,
  ...,
  longitude = NULL,
  latitude = NULL,
  start_date = NULL,
  end_date = NULL,
  label = "NoClass"
)
# S3 method for csv_wtss_cube
sits_get_data(cube, file, ..., bands = NULL)
# S3 method for csv_satveg_cube
sits_get_data(cube, file, ...)
# S3 method for shp_wtss_cube
sits_get_data(
  cube,
  file,
  ...,
  start_date = NULL,
  end_date = NULL,
  bands = NULL,
  label = "NoClass",
  shp_attr = NULL,
  .n_shp_pol = 30
)
# S3 method for shp_satveg_cube
sits_get_data(
  cube,
  file,
  ...,
  start_date = NULL,
  end_date = NULL,
  label = "NoClass",
  shp_attr = NULL,
  .n_shp_pol = 30
)
# S3 method for raster_cube
sits_get_data(
  cube,
  file = NULL,
  ...,
  longitude = NULL,
  latitude = NULL,
  start_date = NULL,
  end_date = NULL,
  bands = NULL,
  label = "NoClass",
  impute_fn = sits_impute_linear()
)
# S3 method for csv_raster_cube
sits_get_data(
  cube,
  file,
  ...,
  bands = NULL,
  impute_fn = sits_impute_linear(),
  multicores = 1,
  .n_pts_csv = NULL
)
# S3 method for shp_raster_cube
sits_get_data(
  cube,
  file,
  ...,
  start_date = NULL,
  end_date = NULL,
  bands = NULL,
  label = "NoClass",
  impute_fn = sits_impute_linear(),
  multicores = 1,
  shp_attr = NULL,
  .n_shp_pol = 30
)

Arguments

cube

Data cube from where data is to be retrieved.

file

File with information on the data to be retrieved.

...

Other parameters to be passed for specific types.

multicores

Number of threads to process the time series.

longitude

Longitude of the chosen location.

latitude

Latitude of the chosen location.

start_date

Start of the interval for the time series in "YYYY-MM-DD" format (optional).

end_date

End of the interval for the time series in "YYYY-MM-DD" format (optional).

bands

Bands to be retrieved (optional).

label

Label to be assigned to the time series (optional).

shp_attr

Attribute in the shapefile to be used as a polygon label.

.n_shp_pol

Number of samples per polygon to be read (for POLYGON or MULTIPOLYGON shapefile).

impute_fn

Imputation function for NA values.

.n_pts_csv

Number of points from CSV file to be retrieved.

Value

A tibble with the metadata and data for each time series <longitude, latitude, start_date, end_date, label, cube, time_series>.

References

Lubia Vinhas, Gilberto Queiroz, Karine Ferreira, Gilberto Camara, Web Services for Big Earth Observation Data. In: XVII Brazilian Symposium on Geoinformatics, 2016, Campos do Jordao. Proceedings of GeoInfo 2016. Sao Jose dos Campos: INPE/SBC, 2016. p.166-177.

Examples

# NOT RUN {
# -- Read a point in a raster data cube

# Create a data cube based on files
data_dir <- system.file("extdata/raster/mod13q1", package = "sits")
raster_cube <- sits_cube(
    source = "LOCAL",
    name = "sinop-2014",
    satellite = "TERRA",
    sensor = "MODIS",
    data_dir = data_dir,
    delim = "_",
    parse_info = c("X1", "X2", "tile", "band", "date")
)

# read the time series of the point from the raster
point_ts <- sits_get_data(raster_cube,
    longitude = -55.554,
    latitude = -11.525
)

# --- Read a set of points described by a CSV file

# read data from a CSV file
csv_file <- system.file("extdata/samples/samples_sinop_crop.csv",
    package = "sits"
)
points_csv <- sits_get_data(raster_cube, file = csv_file)
# }