private static LexoDecimal Middle(LexoDecimal left, LexoDecimal right) { var sum = left.Add(right); var mid = sum.Multiply(LexoDecimal.Half(left.GetSystem())); var scale = left.GetScale() > right.GetScale() ? left.GetScale() : right.GetScale(); if (mid.GetScale() > scale) { var roundDown = mid.SetScale(scale, false); if (roundDown.CompareTo(left) > 0) { return(roundDown); } var roundUp = mid.SetScale(scale, true); if (roundUp.CompareTo(right) < 0) { return(roundUp); } } return(mid); }
private static LexoDecimal Between(LexoDecimal oLeft, LexoDecimal oRight) { if (oLeft.GetSystem() != oRight.GetSystem()) { throw new LexoException("Expected same system"); } var left = oLeft; var right = oRight; LexoDecimal nLeft; if (oLeft.GetScale() < oRight.GetScale()) { nLeft = oRight.SetScale(oLeft.GetScale(), false); if (oLeft.CompareTo(nLeft) >= 0) { return(Middle(oLeft, oRight)); } right = nLeft; } if (oLeft.GetScale() > right.GetScale()) { nLeft = oLeft.SetScale(right.GetScale(), true); if (nLeft.CompareTo(right) >= 0) { return(Middle(oLeft, oRight)); } left = nLeft; } LexoDecimal nRight; for (var scale = left.GetScale(); scale > 0; right = nRight) { var nScale1 = scale - 1; var nLeft1 = left.SetScale(nScale1, true); nRight = right.SetScale(nScale1, false); var cmp = nLeft1.CompareTo(nRight); if (cmp == 0) { return(CheckMid(oLeft, oRight, nLeft1)); } if (nLeft1.CompareTo(nRight) > 0) { break; } scale = nScale1; left = nLeft1; } var mid = Middle(oLeft, oRight, left, right); int nScale; for (var mScale = mid.GetScale(); mScale > 0; mScale = nScale) { nScale = mScale - 1; var nMid = mid.SetScale(nScale); if (oLeft.CompareTo(nMid) >= 0 || nMid.CompareTo(oRight) >= 0) { break; } mid = nMid; } return(mid); }