On Fri, 13 Aug 2010, Raymond Toy wrote:
< On 8/13/10 4:51 PM, Leo Butler wrote:
< > After building 5.22.1 with cmucl 19d, I've
< > got the following errors:
< Perhaps these are bugs in 19d. Cmucl 2010-08 gives no errors in the
< testsuite.
< >
< >
< > Error found in
< > /knoppix-home/work/maxima/sandbox/maxima-5.22.1/tests/rtest4.mac,
< > problem:
< > (86)
< According to the logs, this test was added in Dec 2007. This might be
< an issue with that version of cmucl. IIRC, maxima sometimes computes
< 1^N for very large N. Cmucl would warn about raising a number to a
< large N. At some point cmucl added a test so that 1^N doesn't produce
< that warning, since, obviously, it's not a problem for any N.
The issue here is that the CMUCL from the Ubuntu repositories has a
ridiculously low maximum exponent:
(%i1) is(errcatch(rat(x^2^128)) = []);
(%o1) true
(%i2) rat(x^2^128);
Maxima encountered a Lisp error:
Error in function KERNEL::INTEXP:
The absolute value of 340282366920938463463374607431768211456 exceeds
EXTENSIONS:*INTEXP-MAXIMUM-EXPONENT*.
Automatically continuing.
To enable the Lisp debugger set *debugger-hook* to nil.
(%i3) :lisp EXTENSIONS:*INTEXP-MAXIMUM-EXPONENT*
100000
(%i3) :lisp (setq EXTENSIONS:*INTEXP-MAXIMUM-EXPONENT* (expt 2 129))
680564733841876926926749214863536422912
(%i3) rat(x^2^128);
(%o3) x^340282366920938463463374607431768211456
It seems to me that this test ought to be more careful about
how it does this test, to prevent a spurious error as seen
here.
Is there a low bound on the maximum exponent that Maxima would
like to see? If so, let's implement that.
< >
< > Errors found in
< > /knoppix-home/work/maxima/sandbox/maxima-5.22.1/tests/rtest16.mac,
< > problems:
< > (383)
< This test is fairly new. I'm almost positive this is an issue in 19d
< where (expt 2d0 3) doesn't have full double-float precision.
< > Errors found in
< > /knoppix-home/work/maxima/sandbox/maxima-5.22.1/tests/rtest8.mac,
< > problems:
< > (100 109)
< Tests 100 and 109 were added in Mar 2008. I don't know why cmucl 19d
< fails these. Is the accuracy less than expected?
If anything, it is greater than expected:
********************** Problem 100 ***************
Input:
ev(e4, foo(u) = u)
Result:
[2.0, 0.0, 25, 0]
This differed from the expected result:
[1.999999999999999, 2.220446049250313e-16, 25, 0]
********************** Problem 109 ***************
Input:
ev(e7, alfa = 2, vita = 1)
Result:
[.05296102778655729, 4.85722573273506e-17, 50, 0]
This differed from the expected result:
[.05296102778655729, 5.551115123125782e-17, 50, 0]
Leo
<
< Ray
<
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