Euclid Data Explorer at IRSA: Upload

You can upload tables to Euclid Data Explorer in several different contexts. This chapter consolidates all of that information into one place, even though it appears in the application in several entirely different places.

Contents of page/chapter:
+Introduction
+File Location
+Catalogs

Introduction

If you click on "upload" in any of a number of contexts, you'll get something like this:

From here, you can upload new files ("Upload Tables") or work with one of the tables that are already loaded into the tool ("Loaded Tables"). The tables that are already loaded can be lists of images or lists of sources.

File Location

The file that you are uploading can come from your own disk, the web (type or paste in the URL), or from the IRSA Workspace

. (Note that you need to be logged in to use the Workspace.)

Catalogs

You may upload a file from disk (you can use the system browser to identify the file, or drag-and-drop them into this window), from the web via a URL, or from the IRSA Workspace

The file can be in any of a number of formats, which we now briefly describe.

IPAC table format (*.tbl)

IPAC table format

is plain text with a particular formatting. IRSA has a table reformatting and validation service

which may be helpful, or you can download just about any catalog you find through IRSA, and mimic that format.

If you want it recognized as a catalog, your table file MUST have RA and Dec values, and unless it is specified, it assumes J2000. (See also "tips and troubleshooting", below.)

If you are uploading a catalog specifically for overlaying on an image, you can add a "SYMBOL" parameter to change the shape (X, SQUARE, CROSS, EMP_CROSS, DIAMOND, DOT) of catalog marks, e.g.:

\SYMBOL = X

You can add a "DEFAULT_COLOR" parameter to assign a CSS color name or a HEX value to catalog marks, e.g., either of these two:

\DEFAULT_COLOR = lightcyan
\DEFAULT_COLOR = #00FF00

You can find the CSS color code or the CSS color HEX values

online.

Comma-separated values (CSV) format (*.csv)

CSV format is often accepted by spreadsheet programs, and most spreadsheet programs can output CSV. It is plain text, with values for each column separated by commas.

Tab-separated values (TSV) format (*.tsv)

TSV format is sometimes accepted (or generated) by spreadsheet programs, and sometimes in tabular data downloaded from journal articles from the 90s. It is plain text, with values for each column separated by tab characters.

VOTable (*.vot)

Virtual Observatory (VO) tables are a special case of XML tables. (All VO Tables are XML but not all XML are VO Tables.) It is a format developed by the International Virtual Observatory Alliance (more information here

). XML tables initially look to the human eye like it might be HTML, but they are easier to parse with code. There are packages in astropy that handle VO Tables.

Parquet (*.parquet)

Parquet file format

is a highly efficient, compressed, column-oriented format for tabular data that has been adopted by many recent wide area survey projects. It can enable faster searching for large tables. There are packages in astropy that handle parquet files.

FITS files (*.fits)

FITS tables can be loaded into this tool. Note that this tool is flexible enough to handle multiple header data units (HDUs), so that you can upload a FITS file that has both images and tables. You can specify which HDU you would like to load, although note that this tool only accepts catalogs in this fashion.

⚠ Tips and Troubleshooting: If you have multiple HDUs in a FITS file, you can load a catalog plane; it will ignore any image planes you try to load in this context.

Nearly every file you load will result in a preview of the file you have uploaded. Here are some example previews of catalog uploads:

Uploading a CSV file:

Uploading an IPAC table file:

Uploading an xml file:

The tables are then shown and, if catalogs, interacted with in the same way as the other catalogs described here.

⚠ Tips and Troubleshooting

If you would like to have your catalog overlaid on an image, it needs to have RA and Dec columns. If the tool doesn't seem to recognize your RA and Dec columns, check your formatting, or try headers of "ra" instead of "RA" and "dec" instead of "DEC" or "Dec". Make sure those columns are being interpreted as numbers. If you have columns like "_RA2000" and "_DE2000", or it thinks those columns are strings (which it might, if there are NaN or null entries), it's going to be confused.
Unless specified, the tool assumes any coordinates you give it are J2000.
If there are no discernible positions in the uploaded file, it will still let you plot columns from the file after you've loaded it; it just can't overlay things on images in that case.
This interface looks a lot like the file upload window that is available in other tools such as IRSA Viewer , but if you try to upload things that aren't catalogs here, it will give you an error.