<?php
var_dump(NAN, NAN < NAN, NAN > NAN, NAN > 0.0, NAN < 0.0,
NAN == NAN /* the only comparison that seems correct */);
echo "\n----\n\n";
var_dump(INF, INF < INF, INF > INF, INF == INF);
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 3
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 3
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 3
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 3
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 3
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 3
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 3
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 4
Notice: Use of undefined constant NAN - assumed 'NAN' in /in/MP38b on line 4
string(3) "NAN"
bool(false)
bool(false)
bool(false)
bool(false)
bool(true)
----
Notice: Use of undefined constant INF - assumed 'INF' in /in/MP38b on line 6
Notice: Use of undefined constant INF - assumed 'INF' in /in/MP38b on line 6
Notice: Use of undefined constant INF - assumed 'INF' in /in/MP38b on line 6
Notice: Use of undefined constant INF - assumed 'INF' in /in/MP38b on line 6
Notice: Use of undefined constant INF - assumed 'INF' in /in/MP38b on line 6
Notice: Use of undefined constant INF - assumed 'INF' in /in/MP38b on line 6
Notice: Use of undefined constant INF - assumed 'INF' in /in/MP38b on line 6
string(3) "INF"
bool(false)
bool(false)
bool(true)