Talk About Network

Google


Register and Login
Nick
Password
Register create new account Sign up is FREE and you can post replies, new topics, bookmark posts and more!
Recover lost password


Education > Science > -- Wolfram Rese...
Latest [ Topics | Posts ] Archive Post A New Topic Post a Reply
<< Topic < Post Post 1 of 1 Topic 1804 of 1882
Post > Topic >>

-- Wolfram Research QA process defect: Bug in Mathematica 6 -

by Vladimir Bondarenko <vb@[EMAIL PROTECTED] > Mar 15, 2008 at 12:27 AM

-----------------------------------------------------------------

Maple is OK, while none of the Mathematica versions can calculate
this integral correctly.

-----------------------------------------------------------------
-- NOT FIXED BUGS ARE DANGEROUS:  THEY TEND TO GET MORE SEVERE --
-----------------------------------------------------------------

Quality of CASs is our #1 care.

So our little demo continues.... Hello again from the VM machine
which hopefully soon will be used by CAS manufacturers to the
benefit of their customers.

This example demonstrates YET ANOTHER case of bad defects in the
Wolfram Research Quality Assurance process.  Consider, it cannot
trap & fix efficiently regression bugs.

-----------------------------------------------------------------

N[-Sqrt[3] Log[2-Sqrt[3]]/6 - Sqrt[2] Log[Sqrt[2]-1]/6 - Pi/12]
NIntegrate[1/((1+z^2)^(1/2) + (1+z^2)^(7/2)), {z, 0, Infinity}]

                  0.326115
                  0.326115

-----------------------------------------------------------------

N[Integrate[1/((1+z^2)^(1/2) + (1+z^2)^(7/2)), {z, 0, Infinity}]]

-----------------------------------------------------------------
VERSION           OUTPUT                               RESOLUTION
-----------------------------------------------------------------

Mathematica 6.0   0.849714   <---------------------------- BUG #2

Mathematica 5.2   Unevaluated   <------------------------- BUG #1

Mathematica 4.2   0.849714   <---------------------------- BUG #2

Mathematica 3.0   Unevaluated   <------------------------- BUG #1

-----------------------------------------------------------------

Explanation.

The Unevaluated output is interpreted as a defect in accordance
with our extended point of view of bug we had described, taking
into account its economical aspect.

All Maple versions since 1996 to 2007 calculate this integral
correctly.

-----------------------------------------------------------------

If the same bugs exists through numerous software releases,
I think that is valuable public information.

It just should not happen.

-- Brad Cooper

-----------------------------------------------------------------

Best wishes,

Vladimir Bondarenko

VM and GEMM architect
Co-founder, CEO, Mathematical Director

http://www.cybertester.com/
 Cyber Tester, LLC
http://maple.bug-list.org/
  Maple Bugs Encyclopaedia
http://www.CAS-testing.org/
 CAS Testing

-----------------------------------------------------------------

"We must understand that technologies
like these are the way of the future."

-----------------------------------------------------------------
 




 1 Posts in Topic:
-- Wolfram Research QA process defect: Bug in Mathematica 6 -
Vladimir Bondarenko <v  2008-03-15 00:27:04 

Post A Reply:
  Go here to Signup

AddThis Feed Button


About - Advertising - Contact - Frequently Asked Questions - Privacy Policy - Terms of Use - Signup

Contact
tan12V112 Wed Jul 9 3:14:10 CDT 2008.