/src/main/java/org/htmlunit/util/geometry/Line2D.java
isVertical_ = Math.abs( startX_ - yIntercept_) < epsilon;
isVertical_ = Math.abs ( startX_ - endX_ ) < epsilon;
} public Line2D(final double x1, final double y1, final double x2, final double y2) { startX_ = x1; startY_ = y1; endX_ = x2; endY_ = y2; <extra_id_0> if (isVertical_) { slope_ = Double.NaN; yIntercept_ = Double.NaN; } else { slope_ = (endY_ - startY_) / (endX_ - startX_);