Description of software

The software uses innovation files to produce rank histograms and plots of skill (obs-fcst_mean) against spread (sd). One plot of each type is produced per cycle. Currently, the input data is obtained from innovation files.

Location of source code

The IDL source code can be found at /home/h05/frbr/idl_source_code/rank_histogram_v5.pro

Note that a new program /home/h05/frbr/idl_source_code/rank_histogram_v51.pro will now plot up to 12 histograms, without skill-spread diagrams, on a single page. The required inputs are identical as for the original program.

The code uses library routines written by Andy Heaps (NCAS, University of Reading) and these are accesssed by adding these two lines into your .profile file:

export IDL_PATH=+/usr/local/itt
. /data/nwp1/frbr/TIDLWorkspace/andy_lib/guide4.sh

Method of use - interactive usage

The user must supply information as follows:

  1. A start and end cycle for the analysis.
  2. Details of the innovation file directory and filenames
  3. Next, the user must choose a valid observation group and, based on this choice, a valid observation type.
  4. From the selection observation types, a valid level number must be selected. All the available levels can be selected, if required.

The program will then loop over the specified innovation files and generate (in the working directory) files with names such as N_groupname_variablename_hist.ps, where N is a simple counter, starting at 1 and incrementing by 1.

Method of use - batch mode

  1. The user should make a copy of the IDL source code in his/her working directory.
  2. Next, create a text file called histogram_controlfile in the working directory. This file should contain the following:
    111                                             ; start cycle
    112                                             ; end cycle
    /export/carrot/raid1/brugge/fcst_anal/          ; innovations file directory
    Innovations_qwq   ; XXX    - innovations filename XXXcccYYY
    .txt              ; YYY    - where ccc is the cycle number
    3                 ; selected group (eg 2 Surface, 3 Aircraft, 4 Satwind, etc)
    2                 ; selected type (eg 2 Temperature or theta, 4 u, 5 v, etc)
    -999.9            ; selected level, or -999.9 for all levels
    

    where the records should been changed to reflect the input data and output requirements of the user. The text to the right of the ';' symbols can be kept as a reminder of the meaning of the data records.

    The idl code can now been run in a batch job or, if run interactively, will loop through the specified cycles.

    Example output

    The figures show the output from two cycles-worth of aircraft temperature observations.

    Current code developments

    The ability for the software to use precipitation data from a non-innovation file.