Overview of the RO Python Package

RO is a package of python utilities I wrote to support a telescope control interface (TUI). RO includes many general-purpose utilities, but has an emphasis on the Tkinter GUI extensions, networking, astronomy and cross-platform support (unix, MacOS X and Windows).

Download RO from PyPI (starting with version 2.2.6). Versions older than 2.2.6 are still available from the old repository. You can install RO using easy_install or follow the installation instructions in a README.txt file.

Documentation consists of doc strings in the modules. Use help within python to learn more. In addition, many modules include example or test code at the end; look for if __name__ == "__main__". See the contents below to find the right module. Release notes are in the Version History.

Contents include:

• Alg: various useful algorithms including:
  • GenericCallback, a simple way of creating shim between a caller who wants to send you too little information and the callback function you'd actually like to write.
  • MultiDict: a dictionary whose elements are a list of one or more items. multidict[key] = value adds value to the list of items for the specified key (or starts a new list if key was not present).
  • OrderedDict: a dictionary that preserves the order of information as entered.
• Astro: useful algorithms for astronomy, including conversion between various coordinate systems and time functions. Note that this library is based on an extensive body of work by Pat Wallace and as such requires payment for commercial use.
• CnvUtil: type conversion utilities, including as asBool (unlike bool, accepts common string representations of True or False) and asFloatOrNone (unlike float, returns None for None or "NaN").
• Comm: network communications optimized for Tkinter applications
  • TCPConnection: a nice tcp/ip connection. Written data is automatically queued up and fed out as the connection allows. Received data is processed via a callback. The connection can be disconnected and reconnected. The connection happens in the background (rather than freezing the main loop). Changes in status are reported via a callback.
  • FTPGet (formerly GetFile): retrieve files via ftp. The connection and transfer occur in a background thread, and thus cannot hang up the main loop. Status is reported via a callback. An associated widget RO.Wdg.FTPLog offers a graphical display of file transfer.
• DS9: allows one to easily load images into the ds9 image viewer. Images can be loaded from numpy arrays, binary files or fits files. Warnings:
  • RO.DS9 has a few extra requirements.
  • RO.DS9.DS9Win.showArray does not work on Windows with ds9 3.0.3; this appears to be a bug in ds9 or xpa.
• OS: in essence, additions to the standard "os" module (especially os.path). Includes getPrefsDir (find the standard preferences directory on Mac, Windows or unix), findFiles (recursively search for files whose names match specified patterns and don't match others), and removeDupPaths (remove duplicates from a list of paths).
• Prefs: a complete Tkinter-based preferences implementation, including automatic updating of fonts and colors and programmable updating of other attributes. Includes preferences for fonts, colors, sounds (snack sound library is required to play them), files and directories.
• ScriptRunner: execute user-written scripts that wait for something to happen without halting the main Tkinter event loop. Based on generators.
• SeqUtil: sequence utilities, such as isSequence (returns True if the argument is a sequence), asList (converts one item or a sequence of items to a list), etc.
• StringUtil: string utilities including conversion of sexagesimal (dd:mm:ss and hh:mm:ss) strings to and from numbers.
• Wdg: extensions of the standard Tkinter widgets and useful additional widgets. Almost all widgets support hot help strings (automatically displayed in a StatusBar, see below), linking to html htlp and a contextual menu. RO.Wdg widgets include:
  • Bindings: various useful event bindings, including the ability to make Text and Entry widgets read-only while allowing the user to still copy data and bring up contextual menus. Also improves the standard bindings for Mac users.
  • Entry: entry widgets for integers, floats and sexagesimal (dd:mm:ss and hh:mm:ss) values. Includes range checking and (for sexagesimal values) the ability to omit fields.
  • FTPLogWdg: supports downloading files via ftp or http. Includes a display of all current, past and queued transfers that permits aborting a transfer (but there is no provision for resuming an interrupted transfer). Basically this is like a typical web browser's file transfer manager.
  • Gridder: simplifies gridding widgets that have a label, one or more data widgets and an optional units display. You supply the data display widgets and the gridder generates the label and units widget, auto-increments the row number and so on. The StatusConfigGridder does a similar job for displays that have the current values to the left and user-set new values to the right.
  • Label: widgets for displaying strings, numbers and sexagesimal (dd:mm:ss and hh:mm:ss) values. Also may be set automatically by KeyVariables, and offers integrated support for Prefs.
  • LogWdg and CmdReplyWdg: widgets for displaying logged data. Messages of different severity may be color-coded and shown or hidden. Includes a search function. CmdReplyWdg adds a command bar at the bottom, with a command history.
  • OptionPanelControl: supports showing and hiding panels of optional controls. The idea is somewhat similar to that of a tabbed pane, but multiple optional panels can be shown at one time.
  • ScriptTk: a wrapper around Tkinter.Tk that creates the usual root window but also creates a separate script window, so you can mess with things while your application is running. Formerly ROStdTk.
  • ScrolledWdg: scrollable panel of widgets.
  • SoundPlayer: play sound files using the snack sound library.
  • StatusBar: automatically displays "hot help" strings for RO.Wdg widgets in the same TopLevel. Also displays other messages color-coded by severity. Finally, can automatically display status for a command (a KeyVariable.KeyCommand sent to a KeyDispatcher).
  • Toplevel: allows you to easily create multi-windowing applications that remember window position and which windows were open or closed.
• KeyVariable: KeyVariables are much like Tkinter Tk variables, but have extra capabilities for automatically updating RO.Wdg widgets and calling callbacks when set. See also KeyDispatcher, which can automatically set KeyVariables from keyword-value data and issue commands and track replies.
• procFiles: easy batch processing of files. Differs from "fileinput" in that your user-defined function handles each input file in one call. This makes it very easy to include a header and footer for each file, write a separate output file for each input file, vary the output data depending on the file name and similar tasks. Ideal for drag-and-drop "droplets".

Most of RO is available under the GNU Public License, but RO.Astro has a separate package (see its README.txt for details). The code is offered with no warranty of any kind. RO was partially developed using WingIDE Professional, an excellent integrated development environment. Thanks to the kind folks at WingWare for a free license.

The telescope control interface TUI is very specific to the Apache Point Observatory 3.5m telescope, but source code is available if you would like to examine it.

Russell Owen
University of Washington
PO Box 351580
Seattle, WA 98195-1580
rowen u washington edu
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