今天用此函数做方程求解时发现有误，特此更正：
////// 降阶法计算行列式 /// /// N阶行列式 /// 是否0优化 ///计算结果 public static decimal CalcDeterminantAij(decimal[,] Determinants, bool ZeroOptimization = false) { var theN = Determinants.GetLength(0); //假设为2阶。直接计算 if (theN == 2) { return Determinants[0, 0] * Determinants[1, 1] - Determinants[0, 1] * Determinants[1, 0]; } if (theN == 1) { return Determinants[0, 0]; } if (theN == 0) { throw new Exception("參数错误!"); } if (ZeroOptimization) { //找0最多的行 int theRowIndex = 0; int theMaxZeroCountR = -1; for (int i = 0; i < theN; i++) { int theZeroNum = 0; for (int j = 0; j < theN; j++) { if (Determinants[i, j] == 0) { theZeroNum++; } } if (theZeroNum > theMaxZeroCountR) { theRowIndex = i; theMaxZeroCountR = theZeroNum; } } //找0最多的列 int theColIndex = 0; int theMaxZeroCountC = -1; for (int i = 0; i < theN; i++) { int theZeroNum = 0; for (int j = 0; j < theN; j++) { if (Determinants[j, i] == 0) { theZeroNum++; } } if (theZeroNum > theMaxZeroCountC) { theColIndex = i; theMaxZeroCountC = theZeroNum; } } if (theMaxZeroCountR >= theMaxZeroCountC) { decimal theRetDec = 0; //第i=theRowIndex+1行展开 int i = theRowIndex + 1; for (int j = 1; j <= theN; j++) { var theSign = CalcDeterMijSign(i, j); var theNewMij = GetDeterminantMij(Determinants, i, j); theRetDec += theSign * Determinants[i - 1, j - 1] * CalcDeterminantAij(theNewMij, ZeroOptimization); } return theRetDec; } else { decimal theRetDec = 0; //第j=theColIndex+1列展开 int j = theColIndex + 1; for (int i = 1; i <= theN; i++) { var theSign = CalcDeterMijSign(i, j); var theNewMij = GetDeterminantMij(Determinants, i, j); theRetDec += theSign * Determinants[i, j] * CalcDeterminantAij(theNewMij, ZeroOptimization); } return theRetDec; } } else { //採用随机法展开一行 var i = new Random().Next(1, theN); decimal theRetDec = 0; for (int j = 1; j <= theN; j++) { var theSign = CalcDeterMijSign(i, j); var theNewMij = GetDeterminantMij(Determinants, i, j); //此处改动theRetDec += theSign * Determinants[i, j] * CalcDeterminantAij(theNewMij, ZeroOptimization); theRetDec += theSign * Determinants[i-1, j-1] * CalcDeterminantAij(theNewMij, ZeroOptimization); } return theRetDec; } }