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MathGroup Archive 2005

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ExpToTrig with Real Numbers

  • To: mathgroup at
  • Subject: [mg63334] ExpToTrig with Real Numbers
  • From: "Blimbaum, Jerry CIV NSWC PC" <jerry.blimbaum at>
  • Date: Sat, 24 Dec 2005 07:18:59 -0500 (EST)
  • Sender: owner-wri-mathgroup at
  • Thread-index: AcYH+AuI2LVNWa4RRYe/xe7Lw23ALg==

A calculation gives me the following as a part of the output that I see
on the screen: (i = Imaginary)

-0.262484 i  Exp[-0.951249 i t] +   0.262484 i Exp[0.951249 i t]

I want to apply ExpToTrig and , of course, end up with 0 for the Cosine
part and - .262484*2  Sin [0.951249] for the Sine part ...

instead I get  (which I decided to look at output with InputForm)

(-0.2624844042359744*I)*Cos[0.9512492197250393*t] +
(0.26248440423597375*I)*Cos[0.9512492197250397*t] -
 0.2624844042359744*Sin[0.9512492197250393*t] -

I can see from this that the coefficients and exponent numbers are very
close but not identical  although , I think, in theory they should be.
I'm not worried about the 10th decimal place.    How do i get the result
I want in a general way?

thanks....jerry blimbaum

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