Reading of added variables

[frcm]

The ropp_io package allows to extend the ROprof data type with additional variables; at present, there is no user interface to read this data. This needs to be added.

[(none)]

Milestone 2.0 deleted

[Huw Lewis]

See changeset [1797] - for ROPP release v2.0.

These updates now ensure a netCDF file with any number of additional variables (scalar 0-d, 1-d or 2-d data types) in read in and subsequently written out along with the anticipated variables defined by the ROPP interface file format.

Enhancements to the functionality of ropp_io_read_ncdf_get to enable undefined variables (i.e. not explicitly read using ncdf_getvar call) to be read from an input file, and written out again. i.e. additional variables are preserved on subsequent read/write.

Method:

• In ncdf_open the opened file is checked for the number of variables it contains, and this is saved to a ncdf module variable ncdf_nvars.

• The ncdf module has a new public variable ncdf_read. This is an array of logical statements, set to true in ncdf_getvar for each variable which is read.

• After all explicitly defined variables are read in ropp_io_read_ncdf_get, the ncdf_read variable is checked for each of the ncdf_nvars available variables. For those variables in the input file not yet read, a routine ropp_io_read_ncdf_get_vlistD#d is called, depending on the dimension of the variable to be read in.

• The vlist read routines (in file ropp_io_vlist_read) allocate an element of the Vlist data types in the ROprof structure, depending on the dimensions of the variable to be read. The variable name is found by doing a variable inquiry. Given the name and allocated variable structure, the additional data are read with a call to ncdf_getvar as before.

• Note udunits has been modified to allow output units to be set to input units if the output units are not previously set (e.g. for reading additional variables).

• Added variables are written out as before in ropp_io_write_ncdf_def and ropp_io_write_ncdf_put routines.

Note that it is not envisaged that ROPP will provide functionality to process additional variables - given we can't be expected to know what type of variables may be included. A simple addition to rangechecking procedures may be added however - I will write a new ticket to cover this idea.

ropp2ropp has been successfully tested using additional 1d and 2d data arrays, and cases with more than 1 added variable in a file.

TICKET CLOSED. (See also tickets #7, #141 and #147)