QSAS: A Science Analysis System for Space Plasma Data

QSAS Main Window

Contents:

QSAS Main Window

Overview

Purpose/Function

The QSAS main window is the control centre for QSAS and is opened by the QSAS start up script. Its menus provide access to QSAS functionality, and its scrolling lists hold the data objects for the user to inspect, pass to other QSAS windows, and send results back to. It is a key QSAS design to retain all data and results in memory and available for further use, rather than a single pipeline approach in which data is passed once-only down (and out of) a processing/plotting chain. This enables rapid, flexible explorative analysis.

Use

See the Introductory help page to get started. QSAS sessions invariably start with data selection via the File Menu. Selected data is returned to the top-most scrolling list, from where it may be passed for analysis, display, or export. Time Interval objects are important in space data analysis, and are provided with their own scrolling list in the middle of the window. Useful constants, to which the user may add, are held near the bottom. List management and creation of new time interval or constant objects is through either the Edit menu, right button click on an item or keyboard shortcuts. Objects may also be browsed and edited by double-clicking their names. Throughout all of QSAS, objects are referenced by their text names and path on the working list.

The main window has a toolbar which provides shortcuts to some menu items. This may be toggled on and off using the hide/show toolbar item on the File menu. It is also possible to set in a Profile whether it is on by default at startup.


Working List

Data Objects

The top-most scrolling list holds ingested data and analysis results. These are internally C++ data objects which include all the metadata (units, reference frame, etc.) associated with the object's data. Objects are referenced by text name, and may be passed by various means (see the User Interface discussion in the Introductory Pages).

The values of the data may be browsed by double clicking on the object name to open the Data Object Browser. The slider can be clicked or slid by the usual windows methods to locate any data record. The File Metadata which populates the right pane of the data browser window corresponds variable metadata. Double clicking on the name of an attribute will in turn launch an editor showing its values. Editors allow the data to be viewed and changed. If a change is made it becomes possible to save or save as a new object. All metadata is retained with the object on export. However QSAS only requires 4 entries:

The Working List Data Object Browser

Objects may be dragged and dropped within the working list to change their positions. It is also possible to create folders hierarchically to group data objects, see the Edit menu. Any objects selected at the time a folder is created will be placed in the new folder. Folders may also contain sub-folders, and folders can be dragged and dropped. Objects may also be moved using command + up arrow or Move Up/Down under the File menu.

Time Interval Objects

Time plays a central role in the analysis of space data, and the middle scrolling list on the QSAS Main Window holds Time Interval Objects, which are ordered Start-Stop pairs. QSAS uses Universal Time without leap seconds.

Event tables are also handled by QSAS. These are ordered series of time intervals. They allow the user to store and sort various time intervals, and can be imported from and exported from VO tables.

Throughout QSAS, whenever a time interval is required (e.g., to set the range on a time series plot), there are three methods for the user to specify a time interval:

The Time Interval Object list is managed in the same way as the data list.

Constants

For reference purposes and arithmetic conversions, QSAS provides a set of commonly used constants as data objects. These may be browsed and edited by double clicking, which invokes the Data Object Browser. Additionally, the user may create new constants from the Edit Menu, or dragging an object from the data list.

Temp

The calculator will store intermediate objects on the working list under the Temp folder, and delete them when finished. If a calculation does not complete correctly, then objects here can be inspected to help diagnose the problem.

Data and Time Interval and folders created within them are open by default so that the objects held are visible, they may be closed by clicking on their root decoration to free up visble space on the list and minimise scrolling. The Constants and Temp folders start closed to save space.


Menus

File

The File Menu covers Import (from CEF, CDF or ASCII), Export (to CEF, CDF or ASCII), Save/Restore for the main window and Save/Restore for the whole session, and Quit to close the session. There are two ingestion routes:

Edit

Analysis

Plug-Ins

Plug-ins are separately compiled routines, which may be written by the user or others, typically taking inputs from data objects on the Working List and returning result objects to the Working list.

A set of useful plugins are shipped with QSAS and are separated into two broad categories - Geophysics and Analysis.

The Browse option from the Plug-Ins menu will pop up a file dialog window which can be used to load a third party plug-in compiled separately from QSAS. This is used to select the template file (.qtpl) for a locally developed plug-in that has not been added to the QSAS installation. Selecting this template file will then enable QSAS to read it and construct the appropriate GUI and run the associated shareable object file (.so) containing the executable code. A more detailed explanation is provided in these help pages, but a separate document, Writing QSAS Plugins, provides more detailed information for programmers.

To add a new plug-in into the local QSAS distribution it is necessary to place the new template file in one of the sub-directories of QSAS_HOME/qtpl and the .so/.dll library associated with it into QSAS_HOME/lib.

The sub-directories of QSAS_HOME/qtpl are Analysis, Geophysics, Arithmetic, EventTables, Filtering, UnitOperations and TimeOperations.  The Refresh Menu option under Plug-Ins will then cause the new plug-in to show up under Geophysics or Analysis if it was placed in one of these directories. Alternatively it will appear under the top level menu Analysis if placed in the appropriate directory after restarting QSAS.

Batch Processing

Run Batch File also appears under Plug-Ins. This is a distinct utility that opens a batch processing window. Batch processing is controlled by a script.

Plot

Profiles

Allows the user to either select a predefined user-profile or manage a customised profile using the Edit profiles interface. Profiles contain user-defined parameters specifying the behaviour and look of QSAS.

Help


Right Button Menu

Context sensitive right button option menus are available for some functionality within QSAS. These are provided as short cuts, and the same functions are available through the main Menu Bar or as keyboard shortcuts.

When the right mouse button is clicked with the cursor over an entry on the Working list, a menu is popped up with the following operations, which apply to the selected (single) item on the working list...


Option Settings

There are two toggle selection boxes between the menu bar and the Working List. When selected these control what records are stripped from data objects when they are placed on the Working List. These selections apply to any object placed on the working list irrespective of whether the object is imported from a database, read in from a file or produced internally by operations within QSAS. They are applied at the point of placing the object on the Working list, and stripped records are permanently removed from the QSAS object. If all records in an object are stripped out as the object is transferred to the working list, then the object is empty and will be rejected by the Working List.


Tips/FAQ


Page created by Steve Schwartz, qsassupp@gmail.com

Last up-dated: October 2016 Tony Allen