[esp-r] opinions requested about backward compatibility in ESP-r results libraries

[Jon Hand]

To the ESP-r community of users and developers....

At ESRU we are working on some changes to the zone results library
file which adds in additional data types. The new information
records, for each type of casual gain, the sensible convective, sensible
radiant and latent values (in addition to the usual total radiant and
convective for each zone).

This change has a number of impacts:

a) it allows users to be more specific when graphing and listing and
    doing stats on casual gain related information. You can ask
    for only the occupant sensible convective or only the latent small
    power etc.
b) it includes latent casual gains for the first time
c) it corrects a long-standing glitch for 'controlled' casual
    gains which made it difficult to undertake some lighting
    control assessments.
d) it makes the recovery of information from the results database
    much simpler because almost no post processing is required
    and it will probably be faster because the zone operation file
    should not need to be scanned to support post-processing.

Essentially the new approach takes about 15% of the lines of
code that the previous version and this simplification of the
code is A VERY GOOD THING.

What we are debating at the moment is whether to MAINTAIN
backwards compatibility with older results files in the 'res' module.  
Literally thousands of lines of code clutter could be removed if there
is no requirement for backwards compatibility.

The old format only privided limited choices, it did a rotten
 job for models with lighting control, and for complex models
it slows down results recovery tasks.  We would imagine that
all users would prefer to use the new facility when it becomes
available.

We always attempt to maintain backwards compatibility with
simulation models.  It seems less important for results files
since they can be re-generated easily.  And the truly paranoid
who have 3 year old models will probably also have a 3 year
old version of ESP-r saved as well.

So, if you have a strong opinion one way or another please
send a brief email with your comments.

Regards, Jon Hand