GNU Astronomy Utilities

5 Extensions and Tables

This chapter documents those Gnuastro programs that don’t directly operate on the contents of the data file, they just print information, or convert from different data types. Before working on a FITS file, it is commonly the case that you are not sure how many extensions it has within it and also what each extension is (image, table or blank). In such cases, Header (see Header) can be handy by printing the full header of a FITS file to the terminal for easy inspection.

In other cases you want to use the data in a FITS file in other programs (for example in reports) that don’t recognize the FITS format, for example converting a FITS image into a Jpeg, or PDF format image. ConvertType (see ConvertType) was built for such situations. Finally, the FITS format is not just for images, it can also store tables. Binary tables in particular can be very useful in storing very large catalogs or tables compared to a plain text file. Table (see Table) can be used to choose certain table columns in a FITS table and see them as a human readable output on the terminal, or to save them in another plain text or FITS table.

Read in other formats.

GNU Astronomy Utilities 0.2.28-34fb manual, October 2016.