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[Lapack] bug in dstemr.f when N = 2


Dear Ashutosh,
thanks for the bug report and the fix, all you have written looks correct 
to me, we will patch this,
Julien.


On Thu, 10 Dec 2009, Ashutosh Mahajan wrote:

I think we have a bug in dstemr.f for the case when N is 2. The following
block:

392:                   IF (CS.NE.ZERO) THEN
393:                      ISUPPZ(2*M-1) = 1
394:                      ISUPPZ(2*M-1) = 2
395:                   ELSE
396:                      ISUPPZ(2*M-1) = 1
397:                      ISUPPZ(2*M-1) = 1
398:                   END IF

should really be (note lines 394, 397):

392:                   IF (CS.NE.ZERO) THEN
393:                      ISUPPZ(2*M-1) = 1
394:                      ISUPPZ(2*M) = 2
395:                   ELSE
396:                      ISUPPZ(2*M-1) = 1
397:                      ISUPPZ(2*M) = 1
398:                   END IF

similarly the block:
415:                IF (SN.NE.ZERO) THEN
416:                   IF (CS.NE.ZERO) THEN
417:                      ISUPPZ(2*M-1) = 1
418:                      ISUPPZ(2*M-1) = 2
419:                   ELSE
420:                      ISUPPZ(2*M-1) = 1
421:                      ISUPPZ(2*M-1) = 1
422:                   END IF
423:                ELSE

should really be (note lines 418, 421):

415:                IF (SN.NE.ZERO) THEN
416:                   IF (CS.NE.ZERO) THEN
417:                      ISUPPZ(2*M-1) = 1
418:                      ISUPPZ(2*M) = 2
419:                   ELSE
420:                      ISUPPZ(2*M-1) = 1
421:                      ISUPPZ(2*M) = 1
422:                   END IF
423:                ELSE

--
regards
Ashutosh Mahajan
http://coral.ie.lehigh.edu/~asm4

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