Vis5D Documentation
<<< Previous | Putting Your Data Into Vis5D | Next >>>

# Getting Irregular Data into Vis5D

One method for getting irregular data into vis5d is to use the irregular importer. The 'IRG IMPORT' button can be found on the Vis5D control panel which will invoke the irregular importer. The control panel will be brought up when loading a regular v5d file or it can be brought up by typing

    vis5d -nofile

In the importer there is a "File List." Pressing the "Load File..." button will bring up a file browser where one can select the NetCDF files to load. Any number of NetCDF files may be loaded at one time. Once these files are loaded a list of unique times and variables will be created and displayed. The user can highlight/unhighlight desired times and variables. Frequently there may be a large number of times which do not contain much data. The "FILTER" button can be used to quickly select certain times.

Once the desired files have been selected the user will need to assign a "Dataset Name" and select the memory pool size (default 32M). The "Load" button will then load the selected files and data into vis5d.

The irregular importer can currently read three types of NetCDF files. The first type of file is created by translating the Aviation Routine Weather Reports (METARs) and the Aviation Selected Special Reports (SPECIs) to NetCDF format, using the Unidata decoders. More information about these decoders and METAR data can be found at the Unidata web site. The other two types of data that can be read are METARs converted to the FSL (Forecast Systems Laboratory) NetCDF format and profiles which are also converted to the FSL NetCDF format.

It is possible to read other NetCDF formats with the irregular importer but it requires the addition of source code to the importer. If one is familiar with C programming and the NetCDF file structure it would not be a hard task. The two files: `file.c` and `iapi.c` would require the additions and they are found in the source code.

Sample METAR data in both the Unidata and FSL formats can be downloaded. This tar file also contains a gridded v5d file of an NGM model run. The time frame of this v5d file coincides with the Unidata METAR files. One can overlay both a regular v5d data set and an irregular data set in the same display.

The second method for incorporating irregular data into vis5d is the creation of a new import program or converter. This program would read the user's file format and insert the data into vis5d via the irregular_v5d library calls. The functions that would need to be called and information about them are found in the src file `/vis5d-5.2/src/irregular_v5d.c`. This route for getting irregular data into vis5d is suggested for experienced programmers only.

<<< Previous | Home | Next >>>
User Defined File Formats | Up | McIDAS 3D Grid Data Files