TOPCAT

About

TOPCAT (Tool for OPerations on Catalogues And Tables) is an interactive graphical viewer and editor for tabular data. It is designed to provide most of the facilities astronomers need for analysing and manipulating source catalogues and other tables, though it can also be used with non-astronomical data. It reads a range of astronomical formats (such as FITS, VOTable, and CDF) and general-purpose formats (such as CSV, ASCII, and Parquet), and it is especially suited to exploring very large tables with millions of rows and many columns. Users can browse cell data and table and column metadata, define new columns with algebraic expressions, select row subsets, create interactive plots, calculate statistics, and join tables using flexible matching. Edited tables can be written out in a variety of formats. TOPCAT is a stand-alone application that works without a network connection, and it uses Virtual Observatory standards to interoperate with other tools and services.