===========================================================
variable naming convention:

The Fortran IV variable convention is followed:
i, j, k, l, m, n start integers, which can be long or short
other letters start floats or double

character/string variables start ch, as in chName

logical variables are int, and start lg, as in lgOK

FILE* variables start with io, rest caps, as in ioFILE

when warnings are printed from within code they must all start with string PROBLEM:,
so that all can be found with a pattern search

==============================================================
routine naming:

rule is Noun_Verb, so a routine that does a certain job will have a name like "job_do".  But there are exceptions.

hydrogenic sequence routines start with Hydro....

command parsing routines start with Parse....

routines that create something, one time per coreload, start Create....

==============================================================
format within source files
begin with list of all routines within file
/*cdDrive main routine to call cloudy under all circumstances) */
/*cdReasonGeo wrte why the model stopped and type of geometry on io file
 * continue previous comment */
#include "cddefines.h"
ends with first include

==============================================================

fortran common blocks became structures,
the structure name is the name of the header file

if variables a, b, and c are grouped together into a structure called group,
each is referenced as group.a, group,b and group.c, and are located in the
structure defined in 
group.h

==============================================================

changes denoted by
* >>chng 97 apr 05, remove .5 to get agreement with

note:  only last two digits of year, space, three letters in lower case giving month,
space, then two digit day (01, 09, 10, 30)

reason:  it is then possible to discover all changes made in late may of 2001, with
grep "01 may 2" *.c

==============================================================

tasks that must be done some day, but not an actual problem, are denoted by
/*TODO update following fit to include new reference */
the TODO token is automaticallly picked up by the dotnet task list

==============================================================
fixit()

something that needs to be fixed.  If this routine is ever called then the
code will create a special comment at the end of the calculation saying so.  It should
be used for problems that do affect predictions.

fixit(); /* remove factor of pi from below */

fixit is globally defined so no header is needed (in cddefines.h)

==============================================================

broken();

this is used to indicate that something fundamental has been disturbed 
in the code - I use it when some process has been set to zero (in the code)
as a reminder to unset it.  A warning is generated in the comments if
this routine is ever called.

==============================================================

CodeReview();
CodeReview - placed next to code that needs to be checked 

==============================================================

problems during calculations
any problem discovered during a calculation, which results in a print of some kind,
must have that print begin with the string PROBLEM so that the perl script that
examines output from large grids can detect the problem automatically 

==============================================================
references (atomic data, and methods)

atomic data references denote as follows: ->  indicates a tab
>>refer -> si2 -> cs -> Dufton, P.L., & Kingston, A.E., 1991, MNRAS, 248, 827
>>refer -> fe22 -> as -> Dankwort, W., & Trefftz, E., 1978, A&A 65, 93-98

where more than one line needed
>>refer -> si2 -> cs -> Dufton, P.L., Keenan, F.P., Hibbert, A., 
>>rerercon -> Stafford, R.P., Byrne, P.B., & Agnew, D., 1991, MNRAS, 253, 474

old references, in for history, but no longer used
>>referold -> si2 -> cs -> Dufton, P.L., Keenan, F.P., Hibbert, A., 
>>rereroldcon -> Stafford, R.P., Byrne, P.B., & Agnew, D., 1991, MNRAS, 253, 474

key for type of data is two-letter lower-case word
collision strength cs
transition probability as

species indicated by lower case chemical symbol, followed by ionization stage with no space
