[Date Index] [Thread Index] [Author Index]

Re: Why doesn't TrueQ return True here?

• To: mathgroup at smc.vnet.net
• Subject: [mg119758] Re: Why doesn't TrueQ return True here?
• From: oleksandr_rasputinov at hmamail.com
• Date: Mon, 20 Jun 2011 19:38:27 -0400 (EDT)
• References: <itm0p5$14k$1@smc.vnet.net>

> I would expect TrueQ to return True, not False. Why does it return False?

TrueQ returns True only for an explicitly True argument. That is,

TrueQ = (# === True)&

> And how can I test whether t2-t1 is positive?

For known (or assumed) t1 and t2:

TrueQ@Simplify@Positive[t2-t1]

If either t1 or t2 is undefined, the above returns False. If this is not what
you want, don't use TrueQ here.