From b14689d59b06ec21a9e079c65a0882b7bf457448 Mon Sep 17 00:00:00 2001 From: Miroslav Lichvar Date: Thu, 29 Nov 2012 16:23:22 +0100 Subject: [PATCH] Fix crash and hangs in RGR_FindBestRobustRegression --- regress.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/regress.c b/regress.c index cd5edbd4..3670afb5 100644 --- a/regress.c +++ b/regress.c @@ -588,7 +588,7 @@ RGR_FindBestRobustRegression Estimate standard deviation of b and expand range about b based on that. */ sb = sqrt(s2 * W/V); - if (sb > 0.0) { + if (sb > tol) { incr = 3.0 * sb; } else { incr = 3.0 * tol; @@ -598,6 +598,11 @@ RGR_FindBestRobustRegression bhi = b; do { + /* Make sure incr is significant to blo and bhi */ + while (bhi + incr == bhi || blo - incr == blo) { + incr *= 2; + } + blo -= incr; bhi += incr; @@ -605,8 +610,8 @@ RGR_FindBestRobustRegression eval_robust_residual(x + start, y + start, n_points, blo, &a, &rlo); eval_robust_residual(x + start, y + start, n_points, bhi, &a, &rhi); - } while (rlo * rhi > 0.0); /* fn vals have same sign, i.e. root not - in interval. */ + } while (rlo * rhi >= 0.0); /* fn vals have same sign or one is zero, + i.e. root not in interval (rlo, rhi). */ /* OK, so the root for b lies in (blo, bhi). Start bisecting */ do { @@ -623,7 +628,7 @@ RGR_FindBestRobustRegression } else { assert(0); } - } while ((bhi - blo) > tol); + } while ((bhi - blo) > tol && (bmid - blo) * (bhi - bmid) > 0.0); *b0 = a; *b1 = bmid; -- 2.47.2