Monday, 10/16/2000 Hello, all.
We are making the first announce of the first stable release (1.0) of our package pyclimate, which presents some tools used for climate variability analysis and which make extensive use of Numerical Python and C. It is released under the GNU Public License.
Changes from the previous release
Version 1.0--October, 2000.
1) Improved tests. They are more accurate, reliable, informative, comprehensive and use less disk space.
2) The package compiles using distutils. This feature has been checked on FreeBSD, Linux and OSF platforms.
3) Some minor typos corrected in the documentation.
4) Added KPDF.c, a extension module to estimate univariate and multivariate kernel--based probability density functions.
5) Added a class to compute the vertical component of the curl of a vectorial field in diffoperators.py.
6) DCDFLIB.C is currently distributed with the package.
7) KZFilter.py has been converted into a general purpose LinearFilter.py which holds the basic operations of any linear filter. There are two different subclasses currently, the Lanczos filter and the previous Kolmogorov--Zurbenko filter, KZFilter.py. The user can define new filters just by redefining the filter coefficients subclassing LinearFilter.
The package also contains (from release 0.0): IO functions ------------ -ASCII files (simple, but useful) -ncstruct.py: netCDF structure copier. From a COARDS compliant netCDF file, this module creates a COARDS compliant file, copying the needed attributes, comments, and so on in one call.
Time handling routines ---------------------- * JDTime.py -> Some C/Python functions to convert from date to Scaliger's Julian Day and from Julian Day to date. We are not trying to replace mxDate, but addressing a different problem. In particular, this module contains a routine especially suited to handling monthly time steps for climatological use. * JDTimeHandler.py -> Python module which parses the units attribute of the time variable in a COARDS file and which offsets and scales adequately the time values to read/save date fields.
Interface to DCDFLIB.C ---------------------- A C/Python interface to the free DCDFLIB.C library is provided. This library allows direct and inverse computations of parameters for several probability distribution functions like Chi^2, normal, binomial, F, noncentral F, and many many more.
EOF analysis ------------ Empirical Orthogonal Function analysis based on the SVD decomposition of the data matrix and related functions to test the reliability/degeneracy of eigenvalues (truncation rules). Monte Carlo test of the stability of eigenvectors to temporal subsampling.
SVD decomposition ----------------- SVD decomposition of the correlation matrix of two datasets, functions to compute the expansion coefficients, the squared cumulative covariance fraction and the homogeneous and heterogeneous correlation maps. Monte Carlo test of the stability of singular vectors to temporal subsampling.
Multivariate digital filter --------------------------- Multivariate digital filter (high and low pass) based on the Kolmogorov-Zurbenko filter
Differential operators on the sphere ------------------------------------ Some classes to compute differential operators (gradient and divergence) on a regular latitude/longitude grid.
LICENSE ======= GNU General Public License Version 2.
PREREQUISITES ============= To be able to use it, you will need: 1. Python ;-) 2. netCDF library 3.4 or later 3. Scientific Python, by Konrad Hinsen
IF AND ONLY IF you really want to change the C code (JDTime.[hc] and pycdf.[hc]), then, you will also need SWIG.
COMPILATION =========== Now, we use distutils. The installation is simpler.
DOCUMENTATION ============= Postscript and PDF versions of the manual are included in the distribution. We are preparing an even better version of the documentation.
Any feedback from the users of the package will be really appreciated by the authors.
Jon Saenz, email@example.com Juan Zubillaga, firstname.lastname@example.org Jesus Fernandez, email@example.com
<P><A HREF="http://starship.python.net/crew/jsaenz/pyclimate">PyClimate 1.0</A> - Several routines for the analysis of climate variability. (16-Oct-00)