Difference between area under curve and integrate



This is a abs_integrate bug; if you report it, I'll try to fix it.

--Barton

-----maxima-bounces at math.utexas.edu wrote: -----
To: "Maxima List" <maxima at math.utexas.edu>
From: "Richard Hennessy" 
Sent by: maxima-bounces at math.utexas.edu
Date: 01/08/2012 08:35PM
Subject: Difference between area under curve and integrate

  
 
 
Hi list, 
? 
Is there a way to force Maxima to try to find a real solution to an  integration problem so that it represents the area under the curve in cases  where you get a complex number??  
? 
Consider, 
kill(all)$ 
load(abs_integrate)$ 
rectform(float(rectform(integrate(exp(-signum(x-1)*x^3),x,-1,2)))); 
0.22200130530517 - 1.162123315419017 %i 
? 
If you plot the integrand it is just a real valued function with a well  defined area under it but in this case it gives a complex number for an  answer. 
? 
Rich 
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