On Feb. 14, 2012, I wrote
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> I am not getting erf(%i) to produce a float
> value. So this is a "feature request".
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Two possible routes to the correct answer in terms
of existing Maxima functions are:
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(%i1) %i*float(erfi(1));
(%o1) 1.650425758797543*%i
(%i2) %i*imagpart(expand(float(1-gamma_incomplete(1/2,-1)/sqrt(%pi))));
(%o2) 1.650425758797543*%i
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Ted Woollett