ulmo

Ulmo is a python library for clean, simple and fast access to public hydrology and climatology data.

Installation

Ulmo depends on a lot of libraries from the scientific python stack (namely: numpy, pytables and pandas) and lxml. There are a couple of ways to get these dependencies installed but it can be tricky if doing it by hand. The simplest way to get things up and running is to use a scientific python distribution that will install everything together. A full list is available on numfocus.org but Anaconda is recommended as it is the easiest to set up.

Once the requisite scientific python libraries are installed are installed, the most recent release of ulmo can be installed from pypi. Pip is a good way to do that:

pip install ulmo

Or easy_install:

easy_install ulmo

To install the bleeding edge development version, grab a copy of the source code and run setup.py from the root directory:

python setup.py develop

Quick Start

Check out this brief but awesome tutorial by Nikolay Koldunov to get a sense of what Ulmo is about.

API Reference

• Climate Prediction Center Weekly Drought
• CUAHSI WaterOneFlow
• National Climatic Data Center Climate Index Reference Sequential (CIRS)
• National Climatic Data Center Global Historical Climate Network Daily
• National Climatic Data Center Global Summary of the Day
• Texas Weather Connection Daily Keetch-Byram Drought Index (KBDI)
• US Army Corps of Engineers - Tulsa District Water Control
• USGS National Water Information System

Changelog

0.6.0 (in development)

• this release includes some backwards incompatible changes
• simplified labels used for KBDI values: kbdi_avg -> avg, kbdi_min -> min...
• added parameter_code kwarg to usgs.nwis.hdf5.get_site_data
• added start and end dates to cuahsi.wof.get_values()
• added support for NCDC’s CIRS drought index dataset
• fixed filesystem timestamp related bug that could cause file-based datesets to be unnecessarily re-downloaded
• version number is now available at ulmo.__version__
• misc documentation fixes

0.5.0 (released 2013-05-14)

• nwis.pytables has been replaced with nwis.hdf5 which uses the pandas.io.pytables backend; things should generally run a bit faster now and the code is much cleaner. There is one backwards-incompatible change: nwis.hdf5.get_site() is now thread-safe. There was an undocumented behavior where if a site could not be found in the hdf5 file during a nwis.pytables.get_site() call, then a request to the NWIS service would be made and the site table would be updated but no longer happens. You must explicitly run nwis.hdf5.update_site_list() to update the site list first.
• the nwis.pytables namespace is deprecated in favor of nwis.hdf5 because it is shorter and more recognizable but pytables is still powering things under the hood (via the pandas HDFStore)
• parsed timeseries data dicts from waterml-based datasets (cuahsi.wof and usgs.nwis) now contain parsed site info mapped to the ‘site’ key
• add support for pre-1997 data from CPC’s weekly drought monitor dataset
• bugfix: some related to change of the “current” agricultural year for CPC weekly drought data
• add support for Texas Weather Connection’s Daily Keetch-Byram Drought Index (KBDI) dataset

0.4.1 (released 2013-03-04)

• bugfix: interpret missing data (‘—-‘) correctly in usace.swtwc.get_stations

0.4.0 (released 2013-03-04)

• this release includes some backwards incompatible changes
• usgs.nwis date_range parameter has been replaced with more explicit start, end and period parameters
• ncdc.gsod.get_data() parameters renamed: start_date -> start and end_date -> end to be consistent with other dataset APIs
• ncdc.gsod.get_stations() now allows limiting stations to matching parameters (e.g. country=’US’)
• all date and datetime parameters are now consistently parsed
• added support for CUAHSI’s HIS Central service: ulmo.cuahsi.his_central
• added preliminary support for CPC’s weekly drought monitor dataset (>=1997)
• added preliminary support for data from USACE Tulsa Water District Control

0.3.0 (released 2013-01-14)

• this release includes some backwards incompatible changes
• moved module for USGS NWIS from ulmo.usgs -> ulmo.nwis.usgs
• moved module for WaterOneFlow from ulmo.wof -> ulmo.cuahsi.wof

0.2.4 (released 2013-01-14)

• core API functions can be called from main dataset modules
• support python 2.6

0.2.3 (released 2013-01-13)

• add ghcn daily dataset
• add preliminary support for CUAHSI WOF
• add sphinx documentation
• clean up tests
• make pytables an optional dependency; pytables-related functionality is just disabled if pytables can’t be found

0.2.2 (released 2012-11-05)

• bugfix: broken usgs.pytables last_refresh handling

0.2.1 (released 2012-11-04)

• turn on compression for pytables cache files
• minor bugfix and test cleanup

0.2.0 (released 2012-10-12)

• initial public release as ulmo (formerly pyhis)