pysteps.io¶
Methods for browsing data archives, reading 2d precipitation fields and writing forecasts into files.
pysteps.io.interface¶
Interface for the io module.
get_method(name, method_type) |
Return a callable function for the method corresponding to the given name. |
pysteps.io.archive¶
Utilities for finding archived files that match the given criteria.
find_by_date(date, root_path, path_fmt, …) |
List input files whose timestamp matches the given date. |
pysteps.io.importers¶
Methods for importing files containing two-dimensional radar mosaics.
The methods in this module implement the following interface:
import_xxx(filename, optional arguments)
where xxx is the name (or abbreviation) of the file format and filename is the name of the input file.
The output of each method is a three-element tuple containing a two-dimensional radar mosaic, the corresponding quality field and a metadata dictionary. If the file contains no quality information, the quality field is set to None. Pixels containing missing data are set to nan.
The metadata dictionary contains the following recommended key-value pairs:
| Key | Value |
|---|---|
| projection | PROJ.4-compatible projection definition |
| x1 | x-coordinate of the lower-left corner of the data raster (meters) |
| y1 | y-coordinate of the lower-left corner of the data raster (meters) |
| x2 | x-coordinate of the upper-right corner of the data raster (meters) |
| y2 | y-coordinate of the upper-right corner of the data raster (meters) |
| xpixelsize | grid resolution in x-direction (meters) |
| ypixelsize | grid resolution in y-direction (meters) |
| yorigin | a string specifying the location of the first element in the data raster w.r.t. y-axis: ‘upper’ = upper border ‘lower’ = lower border |
| institution | name of the institution who provides the data |
| unit | the physical unit of the data: ‘mm/h’, ‘mm’ or ‘dBZ’ |
| transform | the transformation of the data: None, ‘dB’, ‘Box-Cox’ or others |
| accutime | the accumulation time in minutes of the data, float |
| threshold | the rain/no rain threshold with the same unit, transformation and accutime of the data. |
| zerovalue | the value assigned to the no rain pixels with the same unit, transformation and accutime of the data. |
| zr_a | the Z-R constant a in Z = a*R**b |
| zr_b | the Z-R exponent b in Z = a*R**b |
Available Importers¶
import_bom_rf3(filename, \*\*kwargs) |
Import a NetCDF radar rainfall product from the BoM Rainfields3. |
import_fmi_geotiff(filename, \*\*kwargs) |
Import a reflectivity field (dBZ) from an FMI GeoTIFF file. |
import_fmi_pgm(filename, \*\*kwargs) |
Import a 8-bit PGM radar reflectivity composite from the FMI archive. |
import_mch_gif(filename, product, unit, accutime) |
Import a 8-bit gif radar reflectivity composite from the MeteoSwiss archive. |
import_mch_hdf5(filename, \*\*kwargs) |
Import a precipitation field (and optionally the quality field) from a MeteoSwiss HDF5 file conforming to the ODIM specification. |
import_mch_metranet(filename, product, unit, …) |
Import a 8-bit bin radar reflectivity composite from the MeteoSwiss archive. |
import_opera_hdf5(filename, \*\*kwargs) |
Import a precipitation field (and optionally the quality field) from an OPERA HDF5 file conforming to the ODIM specification. |
import_knmi_hdf5(filename, \*\*kwargs) |
Import a precipitation or reflectivity field (and optionally the quality field) from a HDF5 file conforming to the KNMI Data Centre specification. |
pysteps.io.nowcast_importers¶
Methods for importing nowcast files.
The methods in this module implement the following interface:
import_xxx(filename, optional arguments)
where xxx is the name (or abbreviation) of the file format and filename is the name of the input file.
The output of each method is a two-element tuple containing the nowcast array and a metadata dictionary.
The metadata dictionary contains the following mandatory key-value pairs:
| Key | Value |
|---|---|
| projection | PROJ.4-compatible projection definition |
| x1 | x-coordinate of the lower-left corner of the data raster (meters) |
| y1 | y-coordinate of the lower-left corner of the data raster (meters) |
| x2 | x-coordinate of the upper-right corner of the data raster (meters) |
| y2 | y-coordinate of the upper-right corner of the data raster (meters) |
| xpixelsize | grid resolution in x-direction (meters) |
| ypixelsize | grid resolution in y-direction (meters) |
| yorigin | a string specifying the location of the first element in the data raster w.r.t. y-axis: ‘upper’ = upper border ‘lower’ = lower border |
| institution | name of the institution who provides the data |
| timestep | time step of the input data (minutes) |
| unit | the physical unit of the data: ‘mm/h’, ‘mm’ or ‘dBZ’ |
| transform | the transformation of the data: None, ‘dB’, ‘Box-Cox’ or others |
| accutime | the accumulation time in minutes of the data, float |
| threshold | the rain/no rain threshold with the same unit, transformation and accutime of the data. |
| zerovalue | it is the value assigned to the no rain pixels with the same unit, transformation and accutime of the data. |
Available Nowcast Importers¶
import_netcdf_pysteps(filename, \*\*kwargs) |
Read a nowcast or a nowcast ensemble from a NetCDF file conforming to the CF 1.7 specification. |
pysteps.io.exporters¶
Methods for exporting forecasts of 2d precipitation fields into various file formats.
Each exporter method in this module has its own initialization function that implements the following interface:
initialize_forecast_exporter_xxx(outpath, outfnprefix, startdate, timestep,
n_timesteps, shape, metadata,
n_ens_members=1,
incremental=None, **kwargs)
where xxx specifies the file format.
This function creates the output files and writes the metadata. See the
documentation of the initialization methods for the format of the output files
and their names. The datasets are written by calling
pysteps.io.exporters.export_forecast_dataset(), and the files are
closed by calling pysteps.io.exporters.close_forecast_files().
The arguments of initialize_forecast_exporter_xxx are described in the following table:
| Argument | Type/values | Description |
|---|---|---|
| outpath | str | output path |
| outfnprefix | str | prefix of output file names |
| startdate | datetime.datetime | start date of the forecast |
| timestep | int | length of the forecast time step (minutes) |
| n_timesteps | int | number of time steps in the forecast this argument is ignored if incremental is set to ‘timestep’. |
| shape | tuple | two-element tuple defining the shape (height,width) of the forecast grids |
| metadata | dict | metadata dictionary containing the projection,x1,x2,y1,y2 and unit attributes described in the documentation of pysteps.io.importers |
| n_ens_members | int | number of ensemble members in the forecast this argument is ignored if incremental is set to ‘member’ |
| incremental | {None, ‘timestep’, ‘member’} | allow incremental writing of datasets the available options are: ‘timestep’ = write a forecast or a forecast ensemble for a given time step ‘member’ = write a forecast sequence for a given ensemble member |
Optional exporter-specific arguments are passed with **kwargs. The return value
is a dictionary containing an exporter object. This can be used with
pysteps.io.exporters.export_forecast_dataset() to write the datasets
to the output files.
Available Exporters¶
initialize_forecast_exporter_geotiff(…[, …]) |
Initialize a GeoTIFF forecast exporter. |
initialize_forecast_exporter_kineros(…[, …]) |
Initialize a KINEROS2 Rainfall .pre file as specified in https://www.tucson.ars.ag.gov/kineros/. |
initialize_forecast_exporter_netcdf(outpath, …) |
Initialize a netCDF forecast exporter. |
Generic functions¶
export_forecast_dataset(field, exporter) |
Write a forecast array into a file. |
close_forecast_files(exporter) |
Close the files associated with a forecast exporter. |
pysteps.io.readers¶
Module with the reader functions.
read_timeseries(inputfns, importer, \*\*kwargs) |
Read a time series of input files using the methods implemented in the pysteps.io.importers module and stack them into a 3d array of shape (num_timesteps, height, width). |