# Observing Dark Worlds — Data

来源：https://www.kaggle.com/competitions/DarkWorlds/data

本地 Meta Kaggle 快照；不是本次实时页面。

# Dataset Description

<p><strong>Training Data</strong></p>
<p>The training data consists of 300 simulated skies similar to the final panel in Figure 2 of the
<a href="https://www.kaggle.com/c/DarkWorlds">description page</a>.&nbsp;Each sky contains between 300 and 740 galaxies. Each galaxy will have an x and y position ranging from 0 to 4200 (units are pixels), and a measure of ellipticity: e1 and e2 (see
<a href="https://www.kaggle.com/c/DarkWorlds/details/an-introduction-to-ellipticity">
An Introduction to Ellipticity</a>).&nbsp;</p>
<p>Training galaxy data is provided in a series of 300 files, one file for each Sky (e.g, Training_Sky27.csv or Training_Sky123.csv). These files have 4 columns:</p>
<ul>
<li>galaxy id </li><li>x-coordinate </li><li>y-coordinate </li><li>e1 </li><li>e2 </li></ul>
<div>Dark matter halo locations in each sky are provided in the file <strong>Training_halos.csv</strong>. This file contains 10 columns, namely:</div>
<div>
<ul>
<li>Sky Id </li><li>number of halos (1, 2 or 3) </li><li>reference x-coordinate&nbsp;(used for evalulation metric) </li><li>reference y-coordinate (used for evalulation metric) </li><li>x-coordinate halo 1 </li><li>y-coordinate halo 1 </li><li>x-coordinate halo 2 </li><li>y-coordinate halo 2 </li><li>x-coordinate halo 3 </li><li>y-coordinate halo 3 </li></ul>
<div>In the case of only two or one halo present there will be zeros in the column.</div>
</div>
<p><strong>Test Data</strong></p>
<p>The test data is in a similar format to the training data. There are 120 simulated skies (see final panel in Figure 2 of the
<a href="https://www.kaggle.com/competitions/wizard/(may%20or%20may%20not%20be%20present)">
description</a>). Each sky contains 300 to 740 galaxies. Each galaxy will have an x and y position ranging from 0 to 4200, e1 and e2 values (totalling 4 columns per galaxy in the sky).</p>
<p>In each sky there are either 1, 2 or 3 dark matter halos. The halo counts in each sky are provided in the file
<strong>Test_haloCounts.csv</strong>.&nbsp;</p>
<p>The challenge is to predict the center of each dark matter halo in each test sky based on the galaxy information provided.</p>