Cluster

Space Plasma Group, Astronomy Unit
Queen Mary
Mile End Road, London E1 4NS, UK

QM : University of London

Qtran: The QM File Translator


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WHAT FOLLOWS IS OUT OF DATE!!

Version 3.4.9 [24 Apr 2007]

This version fixes a bug in writing string array attributes into a new variable when writing cdf files. It also handles
Themis virtual epochs.

Introduction

Qtran is a translator between file formats used by QSAS. In particular, Qtran will convert between CDF files, Cluster Exchange Format files as well as other flat ASCII files of a specified format. It is written by QM as part of our role in the Cluster Science Centre within the UK. The format and software, while written with Cluster in mind, are quite general in applicability, and are used by several groups for a variety of purposes. The Particle Physics and Astronomy Research Council funds this project for the express support of the UK Cluster community, and authorized supply is therefore limited. The software includes a copyright notice and disclaimer. Users are free to modify their own private copies of the software, but should keep the original QM Copyright notice/disclaimer as part of any modified copy. Qtran software is written in C.

From version 3.0 onwards, Qtran also handles CEF 2 syntax files for the Cluster Active Archive.

Obtaining Qtran

Qtran is available as a compressed tar file or compressed Mac install package:

together with the documentation, CU-QMW-TN-0011, for the flat file format(s) which are compatible with Qtran and QSAS:

and the specification, DS-QMW-TN-0010, for Cluster Exchange Format

An earlier version of Qtran (2.7) is also available. This is the last stable version before migration to handling the new CEF 2 syntax and is retained here to provide support for legacy systems.

Compiling Qtran

On Solaris and Linux platforms, cd to src in the Qtran directory and edit the makefile to
locate the local CDF installation.

Qtran is designed to work with CDF version 3.1 or later, but the backward
compatibility flag is set to ensure it writes files that can be read by
cdf 2.7 onwards.  The restriction of using 3.1 onwards is to allow reading
of Themis data files that use epoch16 which is not available in earlier
versions.

To compile Qtran type
make
at the prompt.

This will compile the Qtran executable and place it in the top level Qtran directory.

On Apple Mac machines, download the Qtran.dmg (PowerPC Macs) or Qtran_intel.dmg (Intel Macs) installer
and double click the Qtran package icon.

Running Qtran

Once installed, typing Qtran without any arguments will produce a description of options. Without any options (and just a filename as argument) Qtran will attempt to create a CDF file if the given filename is a .qft or .qfd flat file, and will create a Cluster Exchange (.cef) file if the given filename is a .cdf file. Options, if set, specify the input and output format, control whether an existing file will be overwritten, toggles record numbering, and specify verbose messages. See also Mac specific readme file after Mac OSX installation. NOTE: if the package will not install on a Mac or will only install 0 bytes, it may be necessary to delete the receipt from an earlier Qtran installation - delete the file /Library/Receipts/Qtran.pkg.

Flat File Formats

Flat file formats specified in the above documentation are fixed-width column or delimited ASCII files. Attached or detached headers provide meta-data in a simple parameter-value format which has been designed to facilitate easy mapping to CDF files.

Common Data Format

Qtran has been tested against input CDF files conforming to the Cluster Science Data System (CSDS) specification (see the formal specification document for details). This specification is also compliant with ISTP requirements. Qtran should also cope with most other CDF files as input. On output, Qtran writes CSDS-compliant CDF files.

Authors

Qtran is written by Tony Allen, with the support of the UK CDHF Team at QM/IC.  Please address all comments to csc-support-dl@imperial.ac.uk.

Last up-dated 24 Apr 2007
Send comments and suggestions about this document to csc-support-dl@imperial.ac.uk