For developers

All svn account holders need to familiarize themselves with the following rules.

Sharing I/O channels in SELFE

You need to exercise caution when dealing with parallel I/O especially for writing. For writing outputs, you’d generally let only 1 process do the job, e.g.

if(myrank==0) write(10,*)…..

If you do need to have all processes write e.g. debug messages, you’d then use channel 12 (see below).

Below are all I/O channel numbers used in different sub-models of SELFE (bold numbers mean they have been used by other sub-models and you’d avoid using them). Please add your numbers as soon as you change the code so as to prevent others from using it. A good way to find out if a number is available is to issue the following cmd from src/:

grep "61" */*.F90 -->Looks for '61'

• Hydro/: Channels between 8 and 200 are used by various codes for I/O. In particular:
  • 12: this channel is initialized by different processes to point to files outputs/nonfatal_xxxx, where “xxxx” are the process IDs. Therefore it’s very useful for debugging purpose; you can use it anywhere
  • 101 to 100+noutputs (inclusive of both): reserved for global outputs (including from tracers from sediment, EcoSim, ICM, as well as WWM);
  • 201-250: non-standard outputs (e.g. at sidecenters, prism centers);
  • 251 to 259: reserved for station outputs
  • 10, 31, 32: used for one-off I/O – can be used by other sub-models as long as you close them immediately after use in your part of the code
  • 16: this channel points to mirror.out (on rank 0), the main message output for info about the run. You should use it with if(myrank==0)
• WWM
  • 1100 to 1200: handles for inputs/outputs etc
• EcoSim
  • 600: outputting some messages
• ICM
  • 301 to 323: reading channels for non-point source inputs for ICM
• Sediment
• Sed2D
  • 26

Rules for contributing your code to be included in the SELFE package

Here are some rules for preparing your own code:

• Name all your parallel codes .F90;
• No spaces between “#” (pre-processor) and if/else/end;
• Don’t use “!” inside write/print or any other non-comment portion;
• Try to use the I/O channel number directly, e.g., read(61, etc instead of assigning a number to a variable (e.g. read(ich,). This'd facilitate others searching for conflicts.