[log in to unmask] wrote:
>
> I am in the final stages of retrofitting SIO into our baseline Gismo/GismoApps.
> So now might be the time to set up an SIO punch list:
>
> 1) Pending Masako's confirmation, I believe that Gismo/GismoApps produce
> identical -data- in ASCII and SIO format. On the other hand, I have made
> no provision for SIO to produce the conventional ASCII file -header-
> consisting of the complete geometry description used in the job. How
> should this be handled?
>
> a) I could simply write out the ASCII strings as SIO data.
> b) I could write out the name of the file which the program read to
> get it's geometry data (a little risky ... we have no formal method
> defined to handle desciption file evolution).
> c) We could ignore the problem. (Not good!)
I would prefer a solution along the lines of b), but have no serious
suggestion. Currently the rewritten geometry description is skipped by all
data file readers (except perhaps for the occasional human being).
The only pre-existing versioning we have is via CVS, but how does this work
if someone just wants to make a small change to a standard file, perhaps at
a remote site?
> 2) I am currently writing all floating point numbers as 'float'. Should
> we go to 'double'? I note that the current asc2root converts everything
> to 'float' so the extra precision would be lost there. What would JAS
> prefer? Does it matter? (It could be argued that 'float' precision is
> plenty for hit positions, direction cosines, energy,... . I start
> getting uncomfortable when it comes to things like error matrices
> where even small losses in precision can result in instabilities).
I vote for doubles in critical places at least; I would prefer to go to
doubles entirely if the overhead isn't intolerable. (The new code which
interprets the XML geometry description uses doubles everywhere.)
The Root event classes do appear to use float everywhere, but probably
shouldn't (cal part of FastMC already mostly uses double internally).
Changing them would be tedious but straightforward.
> 6) Anything I've forgotten?
I hope not (and don't think so).
>
> Tony Waite.
Joanne
|