SolrCollapseFunction::__construct

<?php

include "bootstrap.php";

$options = array
(
    'hostname' => SOLR_SERVER_HOSTNAME,
    'login'    => SOLR_SERVER_USERNAME,
    'password' => SOLR_SERVER_PASSWORD,
    'port'     => SOLR_SERVER_PORT,
    'path'     => SOLR_SERVER_PATH
);

$client = new SolrClient($options);

$query = new SolrQuery('*:*');

$func = new SolrCollapseFunction('field_name');

$func->setMax('sum(cscore(),field(some_other_field))');
$func->setSize(100);
$func->setNullPolicy(SolrCollapseFunction::NULLPOLICY_EXPAND);

$query->collapse($func);

$queryResponse = $client->query($query);

$response = $queryResponse->getResponse();

print_r($response);

?>