wiki:ParNCLReleaseNotes1_0_0_b2
Last modified 5 years ago Last modified on 04/08/13 14:55:13

ParNCL 1.0.0b2 - RELEASE NOTES

New Features

This section provides information on the new features available in 1.0.0b2 compared to 1.0.0b1.

  • This version includes support for reading and accessing coordinate variables for all the supported mesh types.
  • This version includes support for more NCL functions: parallel versions of where(), gc_inout() functions.
  • We also support NCL logical statements with distributed data.
  • This version allows creation of distributed data using the NCL function new().
  • The new release also includes several bug fixes to 1.0.0b1 .

Sample NCL scripts

Some sample NCL scripts that work with ParNCL 1.0.0b2 are available here.

Supported NCL Language Features

ParNCL is a parallel version of NCL that runs NCL scripts in parallel and performs data analysis using ParGAL. All the graphics functions in ParNCL are executed serially using existing NCL routines. The features available in ParNCL as of 1.0.0b2 are given below,

Variables

ParNCL supports NCL variables with ancillary data like attributes, dimension and coordinates. The multi-dimensional data stored in climate data files are read by ParNCL using a parallel netcdf reader and distributed across multiple processes that are part of a ParNCL job. ParNCL currently supports accessing attributes, dimensions and coordiantes associated with a variable. ParNCL also supports missing values associated with a data variable (via the "_FillValue" attribute).

ParNCL also supports standard variable subscripting for climate data read from CAM Eulerian Spectral and Finite Volume grids. Range and vector subscripting is supported. This version does not support Coordinate or Named subscripting. It also does not support variable subscripting for the CAM HOMME grid. This support will be added in upcoming releases.

Variables can be assigned to one another and the ancillary data corresponding to the variables are copied as in NCL. File variables in climate data files in the netcdf format can be read using the addfile() and addfiles() functions.

Statements

ParNCL supports blocks, if statements and loop statements like do and while. It also supports user defined and built-in (see the list below) functions and procedures. ParNCL also support logical statements with distributed data.

Supported data-format

ParNCL currently only supports NetCDF files output from either the: CAM Eulerian Spectral grid, CAM Finite Volume grid or CAM Spectral Element (HOMME) grid. We intend to support other types of climate model output in future releases.

Built-in Functions

The list of built-in functions support by ParNCL is given below. Please refer to the NCAR website for more information on these built-in functions.

Supported NCL Functions

The table below gives a summary of the built-in functions supported by ParNCL for each grid type.

Eulerian Spectral GridFinite Volume GridHOMME Grid
addfileYES YESYESOpens a climate data, *.nc, file
addfilesYES YESYESCreates a reference that spans multiple climate data files
dim_avg_nYES YESYESComputes the average of a variable's given dimension(s) at all other dimensions
dim_max_nYES YESYESFinds the maximum of a variable's given dimensions at all other dimensions
dim_min_nYES YESYESFinds the minimum of a variable's given dimensions at all other dimensions
dimsizesYES YESYESReturns the dimension sizes of the input variable
default_fillvalueYES YESYESReturns the default missing value for the given variable type
maxYES YESYESComputes the maximum value of a multi-dimensional array
minYES YESYESComputes the minimum value of a multi-dimensional array
printYES YESYESPrint a variable
printVarSummaryYES YESYESPrint summary of a variable
systemfuncYES YESYESExecutes a shell command and returns the output
uv2vrFYES YESYESComputes vorticity from the wind components on a Fixed grid
uv2vrF_WrapYES YESYESComputes vorticity from the wind components on a Fixed grid.
Retains meta-data associated with the variable
uv2vrGYES YESYESComputes vorticity from the wind components on a Gaussian grid
uv2vrG_WrapYES YESYESComputes vorticity from the wind components on a Gaussian grid.
Retains meta-data associated with the variable
uv2vrAYES YESYESComputes vorticity from the wind components on all supported grid types
uv2vrA_WrapYES YESYESComputes vorticity from the wind components on all supported grid types.
Retains meta-data associated with the variable
uv2dvFYES YESYESComputes divergence from the wind components on a Fixed grid
uv2dvF_WrapYES YESYESComputes divergence from the wind components on a Fixed grid.
Retains meta-data associated with the variable
uv2dvGYES YESYESComputes divergence from the wind components on a Gaussian grid
uv2dvG_WrapYES YESYESComputes divergence from the wind components on a Gaussian grid.
Retains meta-data associated with the variable
uv2dvAYES YESYESComputes divergence from the wind components on all supported grid types
uv2dvA_WrapYES YESYESComputes divergence from the wind components.
Retains meta-data associated with the variable
absYES YESYES
acosYES YESYES
asinYES YESYES
atanYES YESYES
atan2YES YESYES
cosYES YESYES
expYES YESYES
fabsYES YESYES
floorYES YESYES
logYES YESYES
log10YES YESYES
sinYES YESYES
sinhYES YESYES
newYES YESYES Allows user to create an NCL variable
whereYES YESYES Perform array assignments based on a conditional array
gc_inoutsYES YESYES This is a parallel version of the gc_inout() function. More info is available here
VisualizationYES YESYES All NCL graphics routines should work with ParNCL.
These routines are executed serially by ParNCL

Installing ParNCL

You can download ParNCL binaries here.

Information on how to build and install ParNCL from source is available here.

Running an NCL script

Information on how to run an NCL script using ParNCL is available here.

Problems or Questions?

Send email to Parvis-users at lists.mcs.anl.gov