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Calc formula from table

To: mathgroup@smc.vnet.net
Subject: [mg10808] Calc formula from table
From: Pieter van Wyk <modeltec@icon.co.za>
Date: Thu, 5 Feb 1998 00:58:53 -0500
Organization: Modeltec

Could anyone help me: I need to know how to calculate a third order
parabolic
formula from a table. I.o.w. I have a table of data and I need a manual
way to calculate the formula for the curve of the data . 3rd order
formula to be obtained:
Y=AX**3 + BX**2 + CX + D

example data:
y = 338.7    263.5    198.6    150.5    114.7    80.3    55.5    41.9
30.2    19.3    16.5  12.4 10.1
x=  30        40            50        60        70        80 90       
100    110    120    130  140  150

    answer: Y=-0.0002X**3 + 0.0896X**2 -12.945X +651.3

I need a manual method to calculate this formula.

Can it be done without using integration/differentiation. Maybe lin log
exp?

Answers will be appreciated. Regards, Pieter.

Follow-Ups:
- Re: Calc formula from table
  - From: Daniel Lichtblau <danl@wolfram.com>

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