Downloading 1.1.1
Beginning with the 1.1 release, we have considerably expanded the range of distributions for which binary packages are provided. You can now get binary packages for:
- Ubuntu 8.04 through 10.04 (NOTE: please avoid Ubuntu 9.10 32-bit if you can -- see Known Issues below.)
- Fedora 11
- openSUSE 11.1
- Debian 5 (lenny): no "official" support, but the Ubuntu 8.10 packages seem to work well.
- limited support for CentOS 5.3. You have to install your own version of python 2.5 or 2.6 (CentOS does not ship anything higher than 2.4).
Please treat these packages on an as-is basis. We are a small group, and it is simply impossible to thoroughly test the binary installation on so many platforms with our limited manpower (a big organization would probably call this release 1.1.1beta.) So please forgive us if any obvious bugs turn up, report them, and we'll make new binary packages if needed.
First, download an appropriate repository package from http://www.oerc.ox.ac.uk/~meqtrees/repos/astro/release/. Install the repository package with a package installer such as GDebi (your browser will probably offer to run an installer anyway when you go to download the .deb file), or from the command line:
$ sudo dpkg -i oxford-apt-ubuntu-9-10-release.deb
From this point on, the Oxford repository is registered with your package management system, and you can install meqtrees just like any other standard software package supplied by your distro. Use `apt-get` or your favourite package manager (Synaptic, etc.) to refresh the repositories and install the **meqtrees** package. For `apt-get` you would use the following commands:
* {{{$ sudo apt-get update
$ sudo apt-get install meqtrees meqtrees-doc}}}
If you plan to do simulations, you should also install the highly useful **makems** package.
## rpm-based systems (Fedora, openSUSE, CentOS)
A similar procedure applies to rpm-based systems. First, download and install an appropriate repository .rpm from the link above. Your browser will probably offer to run an installer when you go to download the .rpm file. If you prefer the command line, download the .rpm file and install with `rpm`:
* ```
$ sudo rpm -i oxford_astro_release_fedora_11-0.1-1.noarch.rpm
From this point on, the Oxford repository is registered with your package management system, and you can install meqtrees just like any other standard software package supplied by your distro. Use yum or your favourite package manager (Add/remove software, etc.) to refresh the repositories and install the meqtrees package. For yum you would use the following commands:
$ sudo yum update $ sudo yum install meqtrees
## Other recommended software
The **makems** package (available from the same repository) is very useful for simulations, since it can create Measurement Sets for arbitrarily-defined telescopes.
You will probably need a FITS image viewer. We can recommend [[DS9 from SAO|http://hea-www.harvard.edu/RD/ds9/]] (Ubuntu provides it as package **saods9**), or [[Karma|http://www.atnf.csiro.au/computing/software/karma/]] by Richard Gooch (binary tarballs available via the supplied link.) Karma's GUI is dated and quirky compared to DS9, but it is extremely fast and feature-rich, so some people swear by it.
# Known issues and gotchas
## lwimager problems in release 1.1
This should be fixed as of 1.1.1. With 1.1, On some MSs, the lwimager may fail with:
{{{ INFO [[VisSet|VisSet]]::[[VisSet|VisSet]] Adding MODEL_DATA, CORRECTED_DATA and IMAGING_WEIGHT columns Invalid Table operation: Table: cannot add a column }}}
This is a known problem with casacore-1.0.1 and casarest, a bugfix release will be available shortly. In the meantime, you may apply the following workaround to make the MS usable:
* ```
python -c "import pyrap.tables; pyrap.tables.addImagingColumns('foo.MS');"
If the lwimager fails or produces null images, check its text output -- you will probably see a "weights all zero" message. This is because you haven't specified a UV-weighting (or, equivalently, have set it to "default" in the TDL Exec menu.)
The UV-weighting is a persistent parameter: every time you change it, it gets saved in the IMAGING_WEIGHT column of the MS. You can then rerun the imager with "default" weighting to reuse the existing weighting. This is actually pretty useful, since it saves some runtime, and also allows you to manipulate the weights offline. The downside is, if you have a new MS, the IMAGING_WEIGHT column is probably null or missing, so running the imager with "default" weights will fail (and usually confuse you.)
Another confusing imager "feature" is that data flags are only applied during the weighting procedure. Flagged data receives a weight of 0. Flags are not reapplied during subsequent imaging! So if you set your weights, then flag some more data, these flags have no effect on your image until you reset the imaging weights again. I have been caught out by this myself on a number of occasions.
Note also that the CASA imager is built on top of the same casacore/casarest libraries, but it has a fixed default of radial weighting.
Not supported in MeqTrees 1.1, but should be OK again in 1.1.1.
At time of release (26/02/2010), the PyQwt5 package in this distro was broken (see https://bugs.launchpad.net/ubuntu/+source/pyqwt5/+bug/440249). To check if your PyQwt5 is broken, use the following command:
-
$ python -c "from PyQt4 import Qwt5"MeqTrees will run, but none of the visualization tools will work on 9.10 32-bit until Ubuntu has issued an update for PyQwt5. 64-bit was working fine at time of release.
Alternatively, you can build your own PyQwt5 from source, see ["Downloading/BuildingPyQwt5"] for details.
Brave souls may choose to build MeqTrees from source. You will need to check out source from our subversion repository. Please refer to for further instructions.
The old (release 1.0) Downloading page has been renamed to Downloading-1.0.