# Section Requirements

<table><thead><tr><th width="224">Section Type</th><th>Requirements</th></tr></thead><tbody><tr><td>All sections</td><td><ul><li>Data items cannot contain commas.</li><li>Supported line endings are <code>\n, \r\n,</code> and .</li><li>Required characters are all ASCII characters except for <code>*</code> and the control characters <code>CR</code> and <code>LF</code>.</li></ul></td></tr><tr><td>Standalone</td><td><ul><li>Only key-value pairs are supported.</li><li>Each key must have exactly one value.</li><li>The same key cannot be specified more than one time in a single standalone section.</li><li>Opening and closing brackets are both required, and must be the first and last character in the section header line (other than whitespace and commas).</li><li>A standalone section cannot be empty.</li><li>Data in standalone sections must not contain brackets.</li></ul></td></tr><tr><td>Header</td><td><ul><li>There can only be one data item in a section header line.</li><li>Section headers are required to start with an opening square bracket, and end with a closing square bracket</li><li>Opening and closing brackets are both required, and must be the first and last character in the section header line (other than whitespace and commas)</li></ul></td></tr><tr><td>Application</td><td><ul><li>The application name cannot include <code>Settings</code> or <code>Data</code>.</li><li>The application name cannot be empty.</li><li>The application name cannot include -.</li><li>Each application can have a maximum of one <code>Settings</code> section and one <code>Data</code> section.</li></ul></td></tr><tr><td>Application Settings</td><td><ul><li>Settings sections can support only key-value pairs.</li><li>Each key can have only one value.</li><li>The application name cannot include -.</li><li>Applications sections cannot be empty. At least one key-value pair must be specified.</li><li>Keys and values cannot contain <code>[</code> or <code>]</code>.</li><li><mark style="color:red;">Note: The Settings section is applied globally to all samples.</mark></li></ul></td></tr><tr><td>Application Data</td><td><ul><li>For each line that follows the column header line in the application data section, the number of empty plus non-empty data items cannot be less than the number of column headers.</li><li>For each line that follows the column header line in the Application Data section, the number of non-empty values cannot be greater than the number of column headers.</li><li>Column headers must all be unique.</li><li>Each application data section must contain a column header called <code>Sample_ID</code>.</li><li>Column headers and values cannot contain <code>[</code> or <code>]</code>.</li><li><mark style="color:red;">Note: The Data section is uniquely applied to each sample.</mark></li></ul></td></tr></tbody></table>


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