integration error



Maybe this bug was fixed in 5.30?

   (%i66) build_info();
  (%o66) build_info(version="5.30.0",timestamp="2013-06-01 21:29:43",host="i686-pc-mingw32",lisp_name="GNU Common Lisp (GCL)",lisp_version="GCL 2.6.8")

  (%i67) int1:z*(1-z)*log(1-a^2*z*(1-z))$

  (%i68) integrate(int1,z);
  "Is "(a-2)*a^2*(a+2)" positive or negative?"pos;
  (%o68) (-((a^4-2*a^2-8)*log((2*a^2*z-a*sqrt(a^2-4)-a^2)/(2*a^2*z+a*sqrt(a^2-4)-a^2)))/(2*a^3*sqrt(a^2-4))-log(a^2*z^2-a^2*z+1)/2+(4*a^2*z^3-6*a^2*z^2+(-3*a^2-12)*z)/(3*a^2))/6-((2*z^3-3*z^2)*log(1-a^2*(1-z)*z))/6

The error "file_search1: trgsmp.mac not found in file_search_maxima,system." makes me think your Maxima is possibly kaput?

--Barton

________________________________________
From: maxima-bounces at math.utexas.edu [maxima-bounces at math.utexas.edu] on behalf of richard noel fell [fell at brandeis.edu]
Sent: Monday, July 01, 2013 14:02
To: maxima at math.utexas.edu
Subject: integration error

Greetings to all -
With maxima 5.29.1 I find the following bug:

(%i1) int1:z*(1-z)*log(1-a^2*z*(1-z));
                                                                2
(%o1)                                                 log(1 - a  z(1 -
z)) (1 - z) z
(%i2) integrate(int1,z,0,1);
subst: cannot substitute - z for operator z in expression z(1 - z)
  -- an error. To debug this try: debugmode(true);
(%i3) int1:z*(1-z)*log(1-a^2*z*(1-z));
2
(%o3)                                                (1 - z) z log(1 -
a  (1 - z) z)
(%i4) integrate(int1,z,0,1);
Is  a  positive or negative?

p;
Is  a - 2  positive or negative?

n;
file_search1: trgsmp.mac not found in file_search_maxima,system.
#0:
trigsimp(?_l=[-(3*a^3*log(abs(a^2*z^2-a^2*z+1))+(12*a^3*z^3-18*a^3*z^2)*log(a^2*z^2-a^2*z+1)+sqrt(4-a^2)*(6*a^2+1...)
  -- an error. To debug this try: debugmode(true);
(%i5)


Many thanks,
Dick Fell

--
Richard Noel Fell
Fisher School of Physics
Brandeis University
Waltham, Ma 02454
fell at brandeis.edu
       JMJ

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