quad_qags and qag interval bug
- Subject: quad_qags and qag interval bug
- From: Edwin Woollett
- Date: Tue, 27 Mar 2012 16:17:58 -0700
If I use quad_qags or quad_qag to integrate over
an interval [-n, n] an error message results,
changing to interval (-n, n+1) makes the error
message (and error number = 2) go away.
------------------------------------------------------------------------
Maxima 5.26.0 http://maxima.sourceforge.net
using Lisp GNU Common Lisp (GCL) GCL 2.6.8 (a.k.a. GCL)
(%i1) quad_qags(sin(x),x,-1,1);
***MESSAGE FROM ROUTINE DQAGS IN LIBRARY SLATEC.
***INFORMATIVE MESSAGE, PROG CONTINUES, TRACEBACK REQUESTED
* ABNORMAL RETURN
* ERROR NUMBER = 2
*
***END OF MESSAGE
(%o1) [0.0, 1.0165933519183943E-14, 21, 2]
(%i2) quad_qags(sin(x),x,-1,2);
(%o2) [0.95644914241528, 2.0841030850705445E-14, 21, 0]
(%i3) quad_qags(sin(x),x,-2,2);
***MESSAGE FROM ROUTINE DQAGS IN LIBRARY SLATEC.
***INFORMATIVE MESSAGE, PROG CONTINUES, TRACEBACK REQUESTED
* ABNORMAL RETURN
* ERROR NUMBER = 2
*
***END OF MESSAGE
(%o3) [0.0, 3.1278966234842519E-14, 21, 2]
(%i4) quad_qags(sin(x),x,-2,3);
(%o4) [0.5738456600533, 3.7903979626832496E-14, 21, 0]
(%i5) quad_qags(sin(x),x,-3,3);
***MESSAGE FROM ROUTINE DQAGS IN LIBRARY SLATEC.
***INFORMATIVE MESSAGE, PROG CONTINUES, TRACEBACK REQUESTED
* ABNORMAL RETURN
* ERROR NUMBER = 2
*
***END OF MESSAGE
(%o5) [0.0, 4.3812931738840094E-14, 21, 2]
(%i6) build_info();
Maxima version: 5.26.0
Maxima build date: 22:48 1/15/2012
Host type: i686-pc-mingw32
Lisp implementation type: GNU Common Lisp (GCL)
Lisp implementation version: GCL 2.6.8
---------------------------------------------
Same errors show up with quad_qag. Haven't
investigated other quadpack functions.
Ted