2018-XX-YY OSKAR-2.7.1

* Fixed crash when manually specifying which CUDA device to use.

* Fixed display of timing information when using GPU devices.

* Added optimised versions of cross-correlation kernels.

* Refuse to load FITS images with an unknown pixel size.

* Fixed compilation on Ubuntu 18.04.

2017-10-31 OSKAR-2.7.0

* Removed telescope longitude, latitude and altitude from settings file.

These are now specified using "position.txt" in the telescope model.

* Made CUDA an optional dependency, and added option to specify whether

or not to use GPUs for simulations. This makes it possible to run

inside a virtual machine if necessary.

* Removed Qt dependency from all command line applications, and updated

the GUI to use Qt 5.

* Changed GUI to only display settings for the selected application and to

remember the last settings file used for each application.

* Added option to change current working directory from GUI.

* Removed oskar_settings_set, as it was unable to check whether settings

were being set correctly. Settings files can now be updated using

the --set command line option of the required application.

* Added option to specify the number of compute devices used for

simulations (CPU cores and/or GPU cards).

* Added Python interface.

* Re-wrote oskar_imager application to allow use of multiple GPUs

when using a DFT. Visibility data are now loaded in blocks to reduce

memory usage.

* Added option to use a 3D DFT to make images.

* Added option to use gridding and FFT to make images that are

consistent with those from CASA.

* Added option to use W-projection to make images that are

consistent with those from CASA.

* Added option to use natural, radial or uniform visibility weighting

when making images.

* Added option to imager to filter input by UV baseline length,

in wavelengths.

* Fix to ensure pixel coordinates are consistent between

the DFT and FFT algorithms.

* Added options to specify grid kernel parameters.

* Added option to perform imaging in single or double precision,

regardless of the precision of the input data.

* Added capability to use multiple visibility files as input to the imager,

with option to scale image normalisation accordingly.

* Allowed visibility data to be read from a specified column of a

Measurement Set.

* Allowed negative source fluxes.

* Allowed FITS images to be read if they have a diagonal CD matrix

instead of CDELT* values.

2015-06-24 OSKAR-2.6.1

* Changed Measurement Set WEIGHT and SIGMA columns to use a tiled storage

manager, for an approximate 40% improvement in the write performance.

* Restored missing settings log to beam pattern FITS headers.

2015-05-29 OSKAR-2.6.0

* Re-wrote oskar_sim_interferometer application and changed internal

visibility format to allow long interferometer simulations to run

without running out of host memory. A dedicated host thread is now

used to write visibility data, so that computation and file writes are

overlapped as much as possible.

* Re-wrote oskar_sim_beam_pattern application to allow use of multiple

GPUs and to respect the maximum chunk size, so that large images can

be made without running out of GPU memory. A dedicated host thread is now

used to write image data, so that computation and file writes are

overlapped as much as possible.

* Added options to generate beam patterns for specified stations,

or all stations in the telescope model.

* Added option to evaluate beam patterns for specified sky model positions,

instead of an image grid.

* Added option to generate horizon-frame all-sky beam patterns, instead of

using equatorial image coordinates.

* Added options to produce time- and/or channel-averaged beam patterns.

* Added options to produce average cross-power Stokes I beam patterns

for selected stations.

* Added options to save beam pattern data in plain text files instead of,

or as well as, FITS images.

* Added option to select whether cross-correlations or auto-correlations,

or both, should be calculated.

* Contribution from the w-term was omitted from the bandwidth smearing

calculation. This has now been fixed, so the apparent

amplitudes of sources far from the phase centre are slightly reduced.

* Analytical time-average smearing was calculated incorrectly

for sources greater than 90 degrees from the phase centre.

This has now been fixed, so the apparent amplitudes of sources far

from the phase centre are slightly reduced.

* Fixed an issue which could result in repeated log entries.

* Fixed time range start in Measurement Set observation table.

* Added the ability to specify station position errors.

* Added the ability to use numerically-defined element patterns in

scalar mode.

* Moved option to select polarisation mode into telescope model settings

group, so that scalar mode can also be used for beam pattern simulations.

* Added the ability to use seconds (as well as hours, minutes and seconds)

to specify observation length, and the ability to use various

date formats (including MJD number and CASA-style date strings) to

specify the start time.

* Moved and renamed option to allow station beam duplication into

telescope model group.

* Added option to disable horizon clip in advanced sky model settings.

This can save a wasted check if sources are always above the horizon.

* Removed deprecated config.txt telescope model file loader.

* Removed the old orientation.txt telescope model file loader.

Replaced this with feed_angle.txt to allow for a more complete

specification of feed angles in the future.

* Removed options to perform explicit time averaging using multiple

snapshots, as this was very slow.

* Removed options to load GSM maps and HEALPix maps in K, as

amplitude conversion to Jy was not performed correctly.

* Removed options to write OSKAR image files, as these are deprecated.

(Use FITS files instead.)

* Switched to using a counter-based pseudo-random number generator

instead of cuRAND, for increased flexibility and performance.

* Added CRC codes to data chunks in binary files.

* Updated interface to oskar_settings_set binary to unset keys when the

value is left empty.

* Added oskar_vis_upgrade_format application to upgrade visibility files

written by older versions of OSKAR to the new file format.

* Removed oskar_vis_stats application. This functionality is now

provided by oskar_vis_summary using the --stats option.

* Major simplification of system noise settings.

2014-09-09 OSKAR-2.5.1

* Changed the integer range of random seeds to start at 1 (instead of 0).

* Changed settings so that beam normalisation is on by default.

* Further improved efficiency of Measurement Set export, using appropriate

storage managers. This has the additional benefit of making the CASA

imager faster.

* Added the ability to concatenate OSKAR visibility files for different

observation periods into one Measurement Set as an update to the

oskar_vis_to_ms app.

* Added a -q option to suppress command line output log messages for many

of the OSKAR apps.

* Fixed "out of range" error encountered when making a beam pattern with

isotropic elements.

* Fixed "dimension mismatch" error encountered sometimes when using

normalised beams.

* Fixed the scaling of uncorrelated system noise when used with the

Stokes-I only (scalar) mode added in 2.5.0.

2014-07-22 OSKAR-2.5.0

* Changed settings to use a half-wavelength dipole by default,

instead of a geometric dipole.

* Fixed a problem in the telescope model noise loader that caused it to

incorrectly report an error in one situation.

* Removed option to image interferometer output at end of simulation.

(The OSKAR DFT imager is not recommended for general use.)

* Removed element pattern fitting parameters from telescope model settings.

* Created new application to fit element pattern data and write spline

coefficients to a telescope model in OSKAR binary format.

Added new settings group for this.

* Changed element pattern fitting procedure to use Ludwig-3 coordinate

system internally. This generally produces better quality fits for a

given number of knots, and eliminates instability near the zenith.

* Added the ability to specify element pattern data as a function of

frequency. The element data closest to the current observing frequency

is used.

* Added the ability to specify element orientations when using

numerical element pattern data.

* Added the ability to specify multiple element types within a station.

* Added option to use an analytic dipole with a definable length

(in metres or wavelengths) as an element pattern.

* Added option to completely normalise the centre of the station beam

to 1.0 each time it is evaluated. This will effectively perform an

amplitude calibration for a source at the phase centre.

* Added option to turn off the station beam completely

(use the "isotropic" station type for this).

* Added scalar mode option (Stokes I only) to interferometer simulator.

* Added UV range filter for visibility evaluation.

* Added polarised sky model grid generator.

* Added a reference frequency which is used to scale the FWHM of Gaussian

beams for Gaussian beam station types.

* Added run log and settings file to Measurement Set HISTORY table.

(Run log will now be propagated to images made with CASA.)

* Improved efficiency of Measurement Set export.

2014-02-25 OSKAR-2.4.0

* Added ability to specify a set of horizon-based permitted beam directions

on a per-station basis.

* Added ability to save spline data for fitted element patterns back out

to the telescope model. Note, however, that the way numerical element

pattern data is used will change considerably in future versions.

* Fixed an issue building the Google unit test library.

* Changed the behaviour of sky model filters to include the upper bound in

flux, and the lower bound in radius. (Previously, both were excluded.)

2013-11-28 OSKAR-2.3.1

* Fixed an issue building the OSKAR fits library.

* Updated to Google test framework version 1.7.0

2013-11-26 OSKAR-2.3.0

* Renamed applications operating on OSKAR format visibility files

from oskar_visibilities_* to oskar_vis_*.

* Renamed MATLAB interface functions to OSKAR format visibility files

from oskar.visibilities.* to oskar.vis.*

* Fixed memory ordering in MATLAB OSKAR binary file interface for

COMPLEX_MATRIX types.

* Fixed a bug that prevented memory from being inserted correctly into

blocks greater than 2 GiB in size.

* Fixed a bug that prevented blocks of binary data larger than 2 GiB from

being loaded.

* Fixed display of large data blocks in oskar_binary_file_query.

* Fixed incorrect station beam evaluation when using polarised elements

in hierarchical stations.

* Fixed a bug that caused certain visibility noise settings to be ignored.

* Fixed telescope model loader to set element pattern and system noise data

correctly if using a single common station directory.

* Fixed presence of multiple incorrect rows in DATA_DESCRIPTION and

SPECTRAL_WINDOW tables for Measurement Set output.

* Fixed visibility phase for sources greater than 90 degrees from the

phase centre.

* Removed redundant CORRECTED_DATA and MODEL_DATA columns from

Measurement Set output.

* Added per-source rotation measure to sky model.

* Added additional meta-data to the OSKAR visibility structure to record

telescope and station longitudes and latitudes, as well as nominal

station receptor orientations.

* Added options to specify both image dimensions when making beam patterns.

* Added a total intensity (Stokes I auto-correlation) beam pattern output

mode.

* Added check for updates when GUI starts.

* Added warning message if settings file has been edited elsewhere

while simultaneously open in the GUI.

* Added telescope model name, channel bandwidth and time integration

values to visibility files.

* Added percentage time taken for various stages of the simulation to

the message log.

* Added a command line application (oskar_vis_add_noise) to

add uncorrelated noise to visibilities.

* Added application to display a summary of meta-data from an OSKAR

visibility binary file (oskar_vis_summary).

* Added the ability to use separate files to specify station element

positions, gain and phase values, apodisation weights and orientations

in the telescope model.

* Added the ability to use station positions in Earth-centred coordinates.

* Added station type for analytical scalar JVLA dishes, based on the AIPS

task PBCOR. (http://www.aips.nrao.edu/cgi-bin/ZXHLP2.PL?PBCOR)

* Updated options of oskar_image_summary to give the option to display the

settings used to create the image.

* Updated settings for beam pattern generation in order to support the

future addition of new beam pattern types.

2013-03-11 OSKAR-2.2.1

* Fixed a problem that caused compilation to fail on CUDA 1.x architectures.

2013-03-04 OSKAR-2.2.0

* Fixed a subtle bug that could cause element pattern data to be loaded

incorrectly in some telescope configurations, where element pattern data

are present for one station but not for others.

* Fixed incorrect 'power' filename suffix on voltage beam pattern images.

* Changed sky model input file settings to make better use of settings

groups.

* Changed minimum CMake version requirement from 2.8 to 2.6.

* Improved robustness of random-power-law source generators.

* Improved reported error message if visibility file cannot be opened.

* Improved reported error messages if telescope model cannot be loaded.

* Improved chunking of data for complex-to-real DFT, so CUDA kernels

should no longer time-out when imaging large visibility files.

* Added the ability to load a telescope model containing only one station

directory, which will be copied for all remaining stations. This also

applies recursively for sub-stations in sub-directories where relevant.

* Added support for hierarchical beamforming modes, using nested stations.

* Added support for a pointing file, which can be used to override station

beam directions.

* Added options to override reference frequency and spectral index

data for all sources in the sky model.

* Added options to load HEALPix-format FITS files (with RING ordering)

as a sky model component.

* Added (sky model) option to remove sources for which Gaussian width

solutions have failed.

* Added the ability to filter sky model source fluxes after the scale by

spectral index. This is done on a per-channel basis.

* Added the ability to specify the amplitude of points when specifying

generated HEALPix source grids.

* Updated the mex function which reads OSKAR binary tag groups so that

it is possible to specify a user index from which to load the group.

* Updated mex function log and usage messages.

2012-11-20 OSKAR 2.1.1-beta

* Fixed a bug in the MATLAB sky model load and save functions which

caused the reference frequency and spectral index columns to be swapped.

* Fixed a bug which set the minimum flux for the random power law generator

filter to that used for the random broken power law generator filter.

* Added option to use all CUDA devices found on the system, instead of

specifying the list of device IDs. This is now the default behaviour.

2012-10-23 OSKAR 2.1.0-beta

* Fixed a bug which caused visibility data from sky model chunks containing

no sources to be accumulated incorrectly.

* Fixed a bug which caused a list of CUDA device IDs to be ignored if

specified inside quotes.

* Fixed a bug in the OSKAR imager where selection of certain time and

channel ranges incorrectly resulted in an error message, making it

impossible to image a subset of the data cube.

* Fixed simulation of bandwidth smearing for extended sources.

* Added options to allow time-average smearing to be performed analytically.

* Added options and updated the telescope model to allow uncorrelated

noise to be added to the visibility data on a per-station basis.

* Added options to allow an image to be made away from the observation

phase centre.

* Added options to allow an element pattern to have a cosine or Gaussian

tapering function.

* Added MATLAB function for plotting of visibility data.

* Removed message printing when fitting ellipses to Gaussian sources, as

this could result in an unhelpful number of warning messages.

* Updated all telescope model settings for improved clarity.

* Updated options for writing image files.

* The settings GUI now allows for options to be disabled based on the

value of another option. The display of various settings has been updated

to make use of this facility.

2012-07-27 OSKAR 2.0.4-beta

* Fixed a problem encountered when loading a Measurement Set in CASA

containing only one frequency channel.

* Fixed a problem encountered when attempting to load an invalid OSKAR

binary file.

* Fixed uncaught exceptions in simulation applications.

* Added the ability to load FITS images directly as a sky model.

* Added a binary utility to display CUDA system information.

* Added a view filter in the GUI to show and highlight only settings of

interest.

* Removed dependency on main OSKAR library from widgets library and GUI.

2012-06-19 OSKAR 2.0.3-beta

* Fixed a bug that could be encountered when evaluating a station beam

using numerical element pattern data, with incorrect use of work

buffers.

* Fixed a build system bug related to finding CBLAS.

* Added extra parameters to the build system that can be used to override

the location of a number of library dependencies.

* Added a binary utility to convert an OSKAR visibility file to a

Measurement Set.

* Added a binary utility to query the contents of an OSKAR binary file.

* Added help dialog with link to documentation to the OSKAR GUI.

* Updated visibility structure and OSKAR binary file to hold station

coordinates, to be more self-contained.

2012-06-13 OSKAR 2.0.2-beta

* Embedded simulation log in output files.

* Added run progress dialog to show log in GUI, from which simulations can

be cancelled.

* Improved spline fitting procedure and updated default fitting parameters.

* Updated simulation GUI close event behaviour to prompt if there are any

unsaved changes.

* Updated settings interface for the output of beam pattern images to

allow the output of power (amplitude), phase and complex (voltage)

patterns.

* Updated the colour and formatting of options in the settings model used

for the OSKAR GUI in order to highlight the various types of settings

(required options, user specified values and defaults).

* Improved the logic used in the display of the GUI (settings model)

right-click menu.

* Updated the CMake build system to improve compiler compatibility /

portability when building in the default (release) mode.

2012-05-15 OSKAR 2.0.1-beta

* Fixed polarisation simulation by changing element order of R and G Jones

matrices. R is now a standard 2D rotation matrix, and G has elements

ordered theta-phi, rather than phi-theta.

* Fixed handling of settings parameters when using sky model flux filters.

* Fixed logic checks on simulation output file settings.

* Added binary utilities to modify and inspect settings files from

command line or shell scripts.

* Added message box in GUI to indicate when simulations are running.

2012-04-25 OSKAR 2.0.0-beta

* First pre-release.