pg_query_params doesn't substitute parameters

From manual page: https://php.net/function.pg-query-params

Code:

$result = pg_query_params($dbconn_postgres, 'CREATE DATABASE $1', array("Joe's Widgets"));

Error:

PHP Warning:  pg_query_params(): Query failed: ERROR:  syntax error at or near "$1"
LINE 1: CREATE DATABASE $1
                        ^ in /root/db_test.php on line 38

PHP Version:

# php8.1 --version
PHP 8.1.2-1ubuntu2.11 (cli) (built: Feb 22 2023 22:56:18) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.1.2, Copyright (c) Zend Technologies
    with Zend OPcache v8.1.2-1ubuntu2.11, Copyright (c), by Zend Technologies

Postgres version:

psql (PostgreSQL) 15.2 (Ubuntu 15.2-1.pgdg22.04+1)

OS:

Linux [HOSTNAME-EDITED] 5.15.0-69-generic #76-Ubuntu SMP Fri Mar 17 17:19:29 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

Start with the pg_query_params manual page linked in the issue and reproduce the supplied CREATE DATABASE example using PHP 8.1 and PostgreSQL 15. Compare the documented behavior with the observed syntax error, then clarify the page's parameter-substitution guidance and example so the documented usage matches PostgreSQL behavior.