Science Analysis Systems Software
As its name implies, the Science Analysis Systems (SAS) group is responsible for developing and maintaining the software that takes "raw" Level 0 data delivered to it in LAT Data Format (LDF data) and converts it into Level 1 data that is ready for scientific analysis. During this conversion process, event data is reconstructed and events are classified as gamma rays or charged particles.
SAS Software Releases
Each release of Science Analysis Systems software contains many different software packages, and each package is contained in a directory in the main Concurrent Versioning System (CVS) repository. Each package is also tagged, and a tag of a GlastRelease package "seals in concrete" the versions of other packages upon which that package depends. A software release is determined by the version numbers that are contained each package's Configuration Managment Tool 's requirements file, the only place that explicitly specifies the version of each package contained in a release.
Tip: In conjunction with CVS, the Configuration Management Tool (CMT) is used to manage the build of a software release. It is CMT that knows how to do a recursive checkout. MRvcmt is a frontend GUI designed to facilitate such checkouts. Though MRvcmt is the recommended method, developers using a Linux machine may also use glastpack to do recursive checkouts. (See Build Tools.)
SAS software includes top-level checkout packages, applications packages, and constituent packages. An application package (e.g., GLEAM, Em1, Em2, Likelihood Analysis, etc.) has, as its sole purpose, the creation of an executable. For each of the three top-level checkout packages there is a package coordinator, responsible for promoting a specific build to release status. Source code can be obtained from the Concurrent Versions System (CVS) repository, or binary versions of any of the packages can be downloaded using the GLAST Installer.
Note: It is useful to think of the top-level packages as source code toolkits from which you can select the constituent package(s) included in the kit that you will need in order to compile and analyze event information you are interested in.
When you download a checkout package using the GLAST Installer, the external libraries required for that release will be automatically included unless you specify otherwise.
External libraries used by GlastRelease software:
External libraries used by ScienceTools software:
Package and External Library Contents
To view the package and external library contents of code builds, including the version number for each package, click on:
TIP: Pull down menus enable you to select Package, Version, and Tag and, when you click on the Submit button, the external packages are displayed by default; to view the entire package contents of a release, click on All Packages.
The Release Manager software makes a build each time a new version of a package is checked in, whether for GlastRelease, BeamtestRelease, EngineeringModel, or ScienceTool software. It also runs a series of tests to ensure interoperablility with other packages that have been checked in. Developers are notified by e-mail of any test failures related to their package.
Release Manager links provide access to build logs and details of build results, including package lists, test results, errors, date, elapsed time, etc. A Summary Page is provided for each package version and links are also provided to:
Optimized software builds (e.g., rh9_gcc32opt, rhel14_gcc34opt, and VC8) run significantly faster than unoptimized builds, and hence are desirable for event analysis. However, there is also the need to use a debugger during development as well as to track down bugs in production builds; hence, the need for unoptimized builds. While it would be convenient to have both optimized and unoptimized builds of everything readily available, that could quickly create an unnecessary strain on resources such as disk space, and SAS has therefore created the following build classes; each class serving a different function and having a different build frequency:
GlastRelease Red-Dot Summary
Red-Dot Summary pages are displays of packages that have changed when packages in the current release are compared with the packages in the previous release. For example, there are four columns on the GlastRelease Red-Dot Summary page:
GLAST Software Installers
Two GLAST Software Installers are available: a GUI-based installer which can be used by Linux and Windows users, and a Linux Command Line Installer for Linux users only. These installers enable you to download and install the binaries of a top-level package (e.g., GlastRelease, BeamtestRelease, EngineeringModel, or ScienceTools), the External Libraries for those packages, the Configuration Management Tool (CMT) and the ROOT libraries (rootlibs) for GlastRelease, BeamtestRelease, or EngineeringModel.
In addition to GLAST Installer commands, you may also want to familiarize yourself with one the following Build Tools:
For additional Information on SAS Software, also see: