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Author Comment/Response
Michael
05/27/12 07:20am

In Response To 'Re: Re: Re: Re: making a transformation'
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The key is the expression you are applying the replacement to.

Case Init:
In[140]:=
A = 2; B = 4; w = 1000;
FullSimplify[A Cos[w t] - B Sin[w t]]
Out[141]=
2 (Cos[1000 t] - 2 Sin[1000 t])

Case Cleared:
In[142]:=
Clear[A, B, w];
FullSimplify[A Cos[w t] - B Sin[w t]]
Out[143]=
A Cos[t w] - B Sin[t w]

In Case Init, where the coefficients are numbers, the simplified expression has no coefficient in front of Cos. So your pattern, a_ Cos[c_] - b_ Sin[c_], does not match any subexpression.

In Case Cleared, where the coefficient are symbols, the simplified expression does have a coefficient in front of Cos. So your pattern matches the whole expression.

URL: mroge02@emory.edu,

Subject (listing for 'making a transformation')
Author Date Posted
making a transformation Ed Nowak 05/16/12 05:19am
Re: making a transformation Bill Simpson 05/16/12 1:18pm
Re: Re: making a transformation Ed Nowak 05/19/12 00:18am
Re: Re: making a transformation Ed Nowak 05/19/12 02:14am
Re: Re: Re: making a transformation Bill Simpson 05/21/12 00:41am
Re: Re: Re: Re: making a transformation Ed Nowak 05/25/12 01:18am
Re: Re: Re: Re: making a transformation Ed Nowak 05/25/12 02:23am
Re: Re: Re: Re: Re: making a transformation Bill Simpson 05/26/12 10:14pm
Re: Re: Re: Re: Re: Re: making a transformation Ed Nowak 05/28/12 7:22pm
Re: Re: Re: Re: Re: making a transformation Michael 05/27/12 07:20am
Re: making a transformation Ed Nowak 05/18/12 07:25am
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