tclsigmet

tclsigmet − access and manipulate Sigmet data types and files.

2

package require tclsigmet 2
::radar::sigmet::dataTypes
::radar::sigmet::headers ?-name volumeName? fileName
::radar::sigmet::read ?-name volumeName? fileName

The tclsigmet package provides variables and commands that access and manipulate data from Sigmet raw product volumes. When loaded, the package creates a namespace named ::radar::sigmet to store variables and commands related to Sigmet data.

::radar::sigmet::dataTypes

This variable stores a list of known Sigmet data types.

::radar::sigmet::headers ?-name volumeName? fileName

This command reads volume headers for a Sigmet raw product volume from filename. It skips sweep and ray headers, and ray data. It provides a quick look into the volume. If the first character of filename is |, the remainder of fileName is assumed to be a command whose standard output is a Sigmet raw product file. Otherwise, fileName should identify a regular file. If successful ::radar::sigmet::read creates a new Tcl command named RadarName_YYYYMMDDHHMMSS, or volumeName if the -name option is present. This command accesses the volume headers and data.

::radar::sigmet::read ?-name volumeName? fileName

This command reads a Sigmet raw product volume from filename. If the first character of filename is |, the remainder of fileName is assumed to be a command whose standard output is a Sigmet raw product file. Otherwise, fileName should identify a regular file. If successful ::radar::sigmet::read creates a new Tcl command named RadarName_YYYYMMDDHHMMSS, or volumeName if the -name option is present. This command accesses the volume headers and data.

Each Sigmet volume loaded with ::radar::sigmet::read has a corresponding Tcl command that accesses volume headers and data. The behavior of the command is determined by the first word after the command name. The following volume commands are recognized.

volumeName file_type

Always returns "Sigmet".

volumeName header arr_name

This command populates an array named arr_name with header values from volume volumeName. Header types with multiple values, such as sweep_angle, are stored as lists. Header types with multiple values in two dimensions, such as az0, are stored as two dimensional lists (lists of lists). Recognized header types are described in sigmet.h and the IRIS Programmer’s Manual.

volumeName latlon_to_bin s {latitude longitude}

Returns a two element list containing the ray and bin indices of the gate above {latitude longitude}, or nobin if the given point is outside the volume.

volumeName data s y ?r ?b??OR?{lat lon}?

Returns volume data. If call is of form: volumeName data s y the command returns a list with n_rays elements, where n_rays is the number of rays in sweep s. Each element is a list of bin values for sweep s, type y. If call is of form: volumeName data s y r the command returns a list of bin values for sweep s, type y, ray r. If call is of form: volumeName data s y r b the command returns a single bin value for sweep s, type y, ray r, bin b. Indeces start with 0. Type y can be an index or a type name. If call is of form: volumeName data s y {lat lon} the command returns the value for the gate above the given geographic location.
Use volumeName header to get a list of types in the volume. Data elements are floating point values or nodat for bins without data or outside the volume coverage area. Note that some velocity based data, such as DB_VEL and DB_WIDTH are given as a fraction of Nyquist velocity.

volumeName to_dorade s ?name?

Creates a DORADE sweep from sweep s of the volume. This will create a new DORADE sweep managed with a Tcl command named name. If name is not given, a default name will be created and returned. See tcldorade (n), for information on DORADE sweeps in Tcl. This subcommand requires the presence of the tcldorade package.

volume bintvls s y interval_list ?width?

This volume subcommand generates geolinearrays containing outlines of bins with data values in specified ranges. Integer index s identifies the sweep in the volume. Index y identifies the data type. It can be an integer index from the volume types list, or a data type abbreviation. List interval_list specifies the data intervals into which radar bins will be grouped. Each element of interval_list should identify an array with two elements, min and max. The corresponding values should be floating point numbers that give the limits of the data interval. Upon return, each element of interval_list will be the name of a geolinearray containing outlines of bins with data values in the given intervals. For example, suppose interval_list is {foo::arr0 foo::arr1 foo::arr2} with foo::arr0(min) set to -10.0, foo::arr0(max) set to 0.0, foo::arr1(min) set to 0.0, foo::arr1(max) set to 10.0, foo::arr2(min) set to 10.0, and foo::arr2(max) set to 20.0. Then upon return, geolinearray foo:arr0 will contain outlines of radar bins with data values of -10.0 <= data_value < 0.0. Geolinearray foo:arr1 will contain outlines of radar bins with data values of 0.0 <= data_value < 10.0. Geolinearray foo:arr2 will contain outlines of radar bins with data values of 10.0 <= data_value < 20.0. See tclgeomap (n) for information on geolinearrays.

libtclsigmet2.8.so

sigmet (3) IRIS Programmer’s Manual, September 2002.

sigmet, raw product, radar