Please join us on Friday, December 8 at 9 a.m. Pacific (2023-12-08T17:00:00Z) for a tutorial on how to use TOPCAT from your own computer/laptop to access the DP0.2 TAP service. The first hour will feature two presentations by Douglas Tucker (Fermilab). The first presentation will focus on how to gain access to the DP0.2 TAP service from an instance of TOPCAT running on your own laptop/computer. The second presentation will illustrate how to query the DP0.2 database from TOPCAT and then create a color magnitude diagram of bright stars from the query results. By the end of the tutorial, the user should be able to create interactive 3D plots of the data from DP0.2. The presentation will be followed at 10 a.m. Pacific (2023-12-08T18:00:00Z) by breakout sessions where attendees can get assistance with TOPCAT or with other DP0.2 (and DP0.3) questions. Delegates are welcome to join at any time (e.g., just for a breakout session).*
It is recommended that attendees have TOPCAT already installed on their computers ahead of the assembly, although there will be some help on downloading and installing TOPCAT during the assembly. For instructions on how to download and install TOPCAT, please see the TOPCAT install page.
If you want to follow along at the December 8, 2023 DP0 Delegate Assembly and you do not have Java and TOPCAT installed on your computer, please follow the following instructions. If you don’t have them installed before the Assembly, there will be some time during the breakout session afterwards where Rubin staff can help you with the installation.
Ensure you have Java SE 8 or higher installed on your computer/laptop:
TOPCAT is Java-based and requires at least Java SE 8 or higher to run.
Start up a terminal on your computer and issue the command “java -version”
If you have the Oracle version of Java, version 1.8 is equivalent to Java SE 8.
Java SE 8 was released on 18 March 2014; so, if you do have Java on your computer/laptop, it is likely a suitable version.
If you do not have Java SE 8 or higher installed on your laptop, go to one of the following sites to download and install a recent version:
Possibly useful (and possibly misguided!) tips for macOS users with Apple Silicon (ARM architecture), from a TOPCAT newcomer:
You only need the Java runtime environment (JRE), not the larger development environment (JDK). For ARM, the easiest way to get the JRE is via Oracle. The OpenLogic versions of OpenJDK are for Intel (they may run fine via Rosetta, but that’s not optimal). There are ways to get OpenJDK for ARM (e.g., via Homebrew), but Oracle appears to be the quickest and easiest way to get a working ARM JRE (for personal use only).
The TOPCAT macOS installer provides a TOPCAT app that you can put in the Applications folder. But for me it quits immediately upon launch (the TOPCAT website warns there are problems with it).
The TOPCAT FAQ describes workarounds for launching the TOPCAT script or JAR file within the app from a terminal prompt. But the path shown in the FAQ for the JAR file is incorrect for the current version of the app. Either of these commands worked for me:
Summary and Recording of the DP0.2 Assembly, 8 December 2023 – Using TOPCAT with the DP0.2 TAP Service
In the Delegate Assembly on Friday Dec 8, 2023, Douglas Tucker gave two presentations. The first presentation focused on how to gain access to the DP0.2 TAP service from an instance of TOPCAT running on one’s own laptop or computer. The second presentation illustrated how to query the DP0.2 database from TOPCAT and create a color magnitude diagram of bright stars from the query results; it concluded with a demonstration of creating interactive 3D plots from the DP0.2 data.
The Zoom recording of the presentations is available on the Rubin Observatory YouTube channel here .
