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

Re: critical points of a third order polynomial fit (simplification)

• To: mathgroup at smc.vnet.net
• Subject: [mg68481] Re: [mg68466] critical points of a third order polynomial fit (simplification)
• From: "Chris Chiasson" <chris at chiasson.name>
• Date: Mon, 7 Aug 2006 01:40:44 -0400 (EDT)
• References: <200608060656.CAA23460@smc.vnet.net> <5951C758-2C5C-4727-AD67-41E11F62F79E@mimuw.edu.pl> <acbec1a40608060838n1c214499ledaa6ebdc94e0ebc@mail.gmail.com> <A35E92CF-D0AD-4DB3-8BCF-C23ECF0E51A4@mimuw.edu.pl>
• Sender: owner-wri-mathgroup at wolfram.com

Per offlist discussion with Andrzej Kozlowski, it is seen that
Mathematica is capable of detecting the numerical ill conditioning in
this problem when using arbitrary precision numbers. This can be
tested by appending the following replacements to the definition of
bracket:

/. x_Real?InexactNumberQ :> SetPrecision[x, 14]

/. x_Real?InexactNumberQ :> SetPrecision[x, 32]

• References:
  • critical points of a third order polynomial fit (simplification)
    • From: "Chris Chiasson" <chris@chiasson.name>