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2357 lines (2354 loc) · 84.4 KB
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace MatrixTool
{
[Serializable]
public class Matrix
{
/// <summary>
/// 提供矩阵求逆、特殊变换和特殊矩阵生成的方法
/// </summary>
int rows;
int columns;
double[,] value;
/// <summary>
/// 获取矩阵行数
/// </summary>
public int Rows
{
get
{
return rows;
}
set
{
rows = value;
}
}
/// <summary>
/// 获取矩阵列数
/// </summary>
public int Columns
{
get
{
return columns;
}
set
{
columns = value;
}
}
/// <summary>
/// 获取与设置矩阵元素值的二维数组
/// </summary>
public double[,] Value
{
get
{
return this.value;
}
set
{
this.value = value;
}
}
/// <summary>
/// 获取与设置矩阵指定行列元素
/// </summary>
/// <param name="i">行号</param>
/// <param name="j">列号</param>
/// <returns></returns>
public double this[int i, int j]//索引器
{
set
{
this.value[i, j] = value;
}
get
{
return this.value[i, j];
}
}
#region 构造函数
private Matrix()//这是一个快速创建什么字段都没有初始化的矩阵对象的方法,只允许内部使用!
{
}
private Matrix(int rows, int cols)
{
this.rows = rows;
this.columns = cols;
this.value = new double[rows, cols];
}
/// <summary>
/// 构造一个一行一列矩阵
/// </summary>
/// <param name="num"></param>
public Matrix(double num)
{
rows = 1;
columns = 1;
value = new double[1, 1] { {num} };
}
/// <summary>
/// 构造一个行向量
/// </summary>
/// <param name="num"></param>
public Matrix(double[] num)
{
rows = 1;
columns = num.GetLength(0);
value = new double[1,columns];
for (int i = 0; i < columns; i++)
{
value[0, i] = num[i];
}
}
/// <summary>
/// 以二维数组初始化一个矩阵
/// </summary>
/// <param name="num"></param>
public Matrix(double[,] num)
{
rows = num.GetLength(0);
columns = num.GetLength(1);
value = new double[rows, columns];
for (int i = 0; i < rows; i++)
for (int j = 0; j < columns; j++)
value[i, j] = num[i, j];
}
/// <summary>
/// 以指定矩阵初始化一个矩阵(产生一个内容相同引用不同的矩阵)
/// </summary>
/// <param name="inMatrix"></param>
public Matrix(Matrix inMatrix)
{
rows = inMatrix.rows;
columns = inMatrix.columns;
value = new double[rows, columns];
for (int i = 0; i < rows; i++)
for (int j = 0; j < columns; j++)
value[i, j] = inMatrix.value[i, j];
}
#endregion
#region 特殊矩阵生成
/// <summary>
/// 生成一个指定阶的元素全为1的方阵
/// </summary>
/// <param name="dimension"></param>
/// <returns></returns>
public static Matrix Ones(int dimension)
{
Matrix result = new Matrix();
result.rows = dimension;
result.columns = dimension;
result.value = new double[dimension, dimension];
for (int i = 0; i < dimension; i++)
for (int j = 0; j < dimension; j++)
result.value[i, j] = 1;
return result;
}
/// <summary>
/// 生成一个指定行列的元素全为1的矩阵
/// </summary>
/// <param name="row"></param>
/// <param name="column"></param>
/// <returns></returns>
public static Matrix Ones(int row, int column)
{
Matrix result = new Matrix();
result.rows = row;
result.columns = column;
result.value = new double[row, column];
for (int i = 0; i < row; i++)
for (int j = 0; j < column; j++)
result.value[i, j] = 1;
return result;
}
/// <summary>
/// 生成一个指定阶数的单位矩阵
/// </summary>
/// <param name="dimension"></param>
/// <returns></returns>
public static Matrix Eye(int dimension)
{
Matrix result = new Matrix();
result.rows = dimension;
result.columns = dimension;
result.value = new double[dimension, dimension];
for (int i = 0; i < dimension; i++)
for (int j = 0; j < dimension; j++)
{
if (i == j)
result.value[i, j] = 1;
else
result.value[i, j] = 0;
}
return result;
}
/// <summary>
/// 生成一个互换初等矩阵
/// </summary>
/// <param name="dimension"></param>
/// <param name="i"></param>
/// <param name="j"></param>
/// <returns></returns>
public static Matrix ElementarySwitch(int dimension, int i, int j)//互换初等矩阵,i、j行(列)互换
{
if (i >= dimension)
throw new Exception("行列互换初等矩阵互换的行列号必须为0到dimension-1");
if (j >= dimension)
throw new Exception("行列互换初等矩阵互换的行列号必须为0到dimension-1");
Matrix result = Matrix.Eye(dimension);
if (i!=j)
{
result.value[i, i] = 0;
result.value[i, j] = 1;
result.value[j, i] = 1;
result.value[j, j] = 0;
}
return result;
}
/// <summary>
/// 生成一个倍乘初等矩阵
/// </summary>
/// <param name="dimension"></param>
/// <param name="i"></param>
/// <param name="k"></param>
/// <returns></returns>
public static Matrix ElementaryMultiple(int dimension, int i, double k)//倍乘初等矩阵,k倍i行(列)
{
if (i >= dimension)
throw new Exception("倍乘初等矩阵的行列号必须为0到dimension-1");
Matrix result = Matrix.Eye(dimension);
result.value[i, i] = k * result.value[i, i];
return result;
}
/// <summary>
/// 生成一个倍加初等矩阵
/// </summary>
/// <param name="dimension"></param>
/// <param name="i"></param>
/// <param name="k"></param>
/// <param name="j"></param>
/// <returns></returns>
public static Matrix ElementaryMulAdd(int dimension, int i, double k, int j)//倍加初等矩阵,i行加k倍的j行(j列加k倍i列)
{
if (i >= dimension)
throw new Exception("行列倍加初等矩阵倍加的行列号必须为0到dimension-1");
if (j >= dimension)
throw new Exception("行列倍加初等矩阵倍加的行列号必须为0到dimension-1");
Matrix result = Matrix.Eye(dimension);
if (i!=j)
{
result.value[i, j] = k;
}
return result;
}
/// <summary>
/// 生成一个指定阶数的零矩阵
/// </summary>
/// <param name="dimension"></param>
/// <returns></returns>
public static Matrix Zeros(int dimension)
{
Matrix result = new Matrix();
result.rows = dimension;
result.columns = dimension;
result.value = new double[dimension, dimension];
for (int i = 0; i < dimension; i++)
for (int j = 0; j < dimension; j++)
result.value[i, j] = 0;
return result;
}
/// <summary>
/// 生成一个指定行列数的零矩阵
/// </summary>
/// <param name="row"></param>
/// <param name="column"></param>
/// <returns></returns>
public static Matrix Zeros(int row, int column)
{
Matrix result = new Matrix();
result.rows = row;
result.columns = column;
result.value = new double[row, column];
for (int i = 0; i < row; i++)
for (int j = 0; j < column; j++)
result.value[i, j] = 0;
return result;
}
/// <summary>
/// 生成一个指定阶数的伪随机数矩阵
/// </summary>
/// <param name="dimension"></param>
/// <returns></returns>
public static Matrix Random(int dimension)
{
Matrix result = new Matrix();
result.rows = dimension;
result.columns = dimension;
result.value = new double[dimension, dimension];
for (int i = 0; i < dimension; i++)
for (int j = 0; j < dimension; j++)
result.value[i, j] = Matrix.GetRandomNum();
return result;
}
/// <summary>
/// 生成一个指定行列数的伪随机数矩阵
/// </summary>
/// <param name="row"></param>
/// <param name="column"></param>
/// <returns></returns>
public static Matrix Random(int row, int column)
{
Matrix result = new Matrix();
result.rows = row;
result.columns = column;
result.value = new double[row, column];
for (int i = 0; i < row; i++)
for (int j = 0; j < column; j++)
result.value[i, j] = Matrix.GetRandomNum();
return result;
}
/// <summary>
/// 生成一个指定阶数和随机范围的伪随机数矩阵
/// </summary>
/// <param name="dimension"></param>
/// <param name="min">伪随机数下限</param>
/// <param name="max">伪随机数上限</param>
/// <returns></returns>
public static Matrix Random(int dimension, double min, double max)
{
if (min > max)
{
min = max + min;
max = min - max;
min = min - max;
}
Matrix result = new Matrix();
result.rows = dimension;
result.columns = dimension;
result.value = new double[dimension, dimension];
for (int i = 0; i < dimension; i++)
for (int j = 0; j < dimension; j++)
result.value[i, j] = Matrix.GetRandomNum() * (max - min) + min;
return result;
}
/// <summary>
/// 生成一个指定行列数和伪随机数范围的矩阵
/// </summary>
/// <param name="row"></param>
/// <param name="column"></param>
/// <param name="min">伪随机数下限</param>
/// <param name="max">伪随机数上限</param>
/// <returns></returns>
public static Matrix Random(int row, int column, double min, double max)
{
if (min > max)
{
min = max + min;
max = min - max;
min = min - max;
}
Matrix result = new Matrix();
result.rows = row;
result.columns = column;
result.value = new double[row, column];
for (int i = 0; i < row; i++)
for (int j = 0; j < column; j++)
{
result.value[i, j] = Matrix.GetRandomNum() * (max - min) + min;
}
return result;
}
/// <summary>
/// 生成一个由指定数组元素填充对角线的对角矩阵
/// </summary>
/// <param name="diag"></param>
/// <returns></returns>
public static Matrix Diagonal(double[] diag)
{
Matrix result = Matrix.Zeros(diag.GetLength(0));
for (int i = 0; i < result.rows; i++)
{
result.value[i, i] = diag[i];
}
return result;
}
/// <summary>
/// 生成一个指定对角元素和行列数的对角矩阵
/// </summary>
/// <param name="diag"></param>
/// <param name="row"></param>
/// <param name="column"></param>
/// <returns></returns>
public static Matrix Diagonal(double[] diag,int row, int column)
{
Matrix result = Matrix.Zeros(row, column);
int num = row > column ? column : row;
num = num > diag.GetLength(0) ? diag.GetLength(0) : num;
for (int i = 0; i < num; i++)
{
result.value[i, i] = diag[i];
}
return result;
}
/// <summary>
/// 生成一个指定对角元素和偏移量的对角矩阵
/// </summary>
/// <param name="diag"></param>
/// <param name="move">偏移量为正表示向右移,为负表示向左移</param>
/// <returns></returns>
public static Matrix Diagonal(double[] diag, int move)
{
Matrix result = Matrix.Zeros(diag.GetLength(0));
for (int i = 0; i < result.rows; i++)
{
int col=(i + move) % result.columns;
col = col >= 0 ? col : (col + result.columns);
result.value[i, col] = diag[i];
}
return result;
}
/// <summary>
/// 生成一个取参数矩阵上三角部分元素矩阵
/// </summary>
/// <param name="x"></param>
/// <param name="fill">默认其他元素填充为0,可设置</param>
/// <returns></returns>
public static Matrix TriUp(Matrix x, double fill = 0)//上三角
{
Matrix result = new Matrix(x);
for (int i = 0; i < result.rows; i++)
{
for (int j = 0; j < result.columns; j++)
{
if (i > j)
{
result.value[i, j] = fill;
}
}
}
return result;
}
/// <summary>
/// 生成一个取参数矩阵下三角部分元素矩阵
/// </summary>
/// <param name="x"></param>
/// <param name="fill">默认其他元素填充为0,可设置</param>
/// <returns></returns>
public static Matrix TriLow(Matrix x, double fill = 0)//下三角
{
Matrix result = new Matrix(x);
for (int i = 0; i < result.rows; i++)
{
for (int j = 0; j < result.columns; j++)
{
if (i < j)
{
result.value[i, j] = fill;
}
}
}
return result;
}
/// <summary>
/// 生成一个对称矩阵
/// </summary>
/// <param name="x"></param>
/// <param name="reverse">默认为false,为true表示保留下三角部分元素</param>
/// <returns></returns>
public static Matrix Symmetry(Matrix x, bool reverse=false)//对称,inverse参数表示将上三角(下三角)对称到下方(上方)
{
Matrix result = new Matrix(x);
int num = x.rows < x.columns ? x.rows : x.columns;
result = Matrix.SubMatrix(x, num, num);
if (!reverse)
{
for (int i = 0; i < x.rows; i++)
{
for (int j = 0; j < x.columns; j++)
{
if (i > j)
{
result.value[i, j] = result.value[j, i];
}
}
}
}
else
{
for (int i = 0; i < x.rows; i++)
{
for (int j = 0; j < x.columns; j++)
{
if (i < j)
{
result.value[i, j] = result.value[j, i];
}
}
}
}
return result;
}
/// <summary>
/// 生成一个反对称矩阵
/// </summary>
/// <param name="x"></param>
/// <param name="reverse">默认为false,为true表示保留下三角部分元素</param>
/// <returns></returns>
public static Matrix Antisymmetry(Matrix x, bool reverse = false)//反对称,inverse参数表示将上三角(下三角)反对称到下方(上方)
{
Matrix result = new Matrix(x);
int num = x.rows < x.columns ? x.rows : x.columns;
result = Matrix.SubMatrix(x, num, num);
if (!reverse)
{
for (int i = 0; i < x.rows; i++)
{
for (int j = 0; j < x.columns; j++)
{
if (i > j)
{
result.value[i, j] = -result.value[j, i];
}
}
result.value[i, i] = 0;
}
}
else
{
for (int i = 0; i < x.rows; i++)
{
for (int j = 0; j < x.columns; j++)
{
if (i < j)
{
result.value[i, j] = -result.value[j, i];
}
}
result.value[i, i] = 0;
}
}
return result;
}
/// <summary>
/// 生成一个平面坐标旋转变换矩阵(结构力学中由局部坐标系到整体坐标系转换)
/// </summary>
/// <param name="angle">顺时针旋转角度值(不是弧度)</param>
/// <returns></returns>
public static Matrix TransMatrix(double angle)//转换矩阵,结构力学局部坐标系到整体坐标系转换
{
double cosVal = Math.Cos(angle * Math.PI / 180);
double sinVal = Math.Sin(angle * Math.PI / 180);
return new Matrix(new double[6, 6]{{cosVal,sinVal,0,0,0,0},{-sinVal,cosVal,0,0,0,0},{0,0,1,0,0,0},
{0,0,0,cosVal,sinVal,0},{0,0,0,-sinVal,cosVal,0},{0,0,0,0,0,1}});
}
/// <summary>
/// 生成一个平面刚架计算的刚度矩阵(结构力学)
/// </summary>
/// <param name="EI">弯曲刚度</param>
/// <param name="EA">拉压刚度</param>
/// <param name="L">刚架长度</param>
/// <returns></returns>
public static Matrix StiffnessMatrix(double EI, double EA,double L)//刚度矩阵//结构力学
{
return new Matrix(new double[6, 6]{{EA/L,0,0,-EA/L,0,0},{0,12*EI/(L*L*L),6*EI/(L*L),0,-12*EI/(L*L*L),6*EI/(L*L)},
{0,6*EI/(L*L),4*EI/L,0,-6*EI/(L*L),2*EI/L},{-EA/L,0,0,EA/L,0,0},
{0,-12*EI/(L*L*L),-6*EI/(L*L),0,12*EI/(L*L*L),-6*EI/(L*L)},
{0,6*EI/(L*L),2*EI/L,0,-6*EI/(L*L),4*EI/L}});
}
/// <summary>
/// 生成一个指定范围行向量(默认步距为1)
/// </summary>
/// <param name="begin">起始值</param>
/// <param name="end">终止值</param>
/// <returns></returns>
public static Matrix RangeVector(double begin, double end)
{
Matrix result = Matrix.Zeros(1, (int)Math.Floor(Math.Abs(end - begin))+1);
double incre = end >= begin ? 1 : -1;
int i = 0;
for (double x = begin; i<result.columns; x += incre)
{
result.value[0, i++] = x;
}
return result;
}
/// <summary>
/// 生成一个指定范围和步距的行向量
/// </summary>
/// <param name="begin">起始值</param>
/// <param name="incre">步距</param>
/// <param name="end">终止值</param>
/// <returns></returns>
public static Matrix RangeVector(double begin, double incre, double end)
{
if (end >= begin && incre < 0)
throw new Exception("IncreaseVector函数使用时试图由小数递减到大数");
if (end <= begin && incre > 0)
throw new Exception("IncreaseVector函数使用时试图由大数递增到小数");
if (incre == 0)
throw new Exception("IncreaseVector函数使用时递增量为0错误");
Matrix result = Matrix.Ones(1, (int)Math.Floor((end - begin) / incre) + 1);
decimal val = (decimal)begin;
for (int i = 0; i < result.columns; i++)
{
result.value[0, i] = result.value[0, i] * (double)val;
val += (decimal)incre;
}
return result;
}
/// <summary>
/// 生成一个线性空间行向量
/// </summary>
/// <param name="begin">起始值</param>
/// <param name="end">终止值</param>
/// <param name="num">元素个数</param>
/// <returns></returns>
public static Matrix LinspaceVector(double begin, double end, int num)
{
Matrix result = new Matrix(1, num + 1);
for (int i = 0; i <= num; i++)
{
result.value[0, i] = i * (end - begin) / num + begin;
}
return result;
}
/// <summary>
/// 生成一个对数空间行向量
/// </summary>
/// <param name="begin">起始值</param>
/// <param name="end">终止值</param>
/// <param name="num">元素个数</param>
/// <returns></returns>
public static Matrix LogspaceVector(double begin, double end, int num)
{
Matrix result = new Matrix(1, num + 1);
for (int i = 0; i <= num; i++)
{
result.value[0, i] = Math.Pow(10, i * (end - begin) / num + begin);
}
return result;
}
#endregion
#region 矩阵的控制台显示
/// <summary>
/// 在控制台显示矩阵
/// </summary>
public void DisplayInConsole()
{
for(int i=0;i<rows;i++)
for (int j = 0; j < columns; j++)
{
if (j == 0)
Console.Write("[");
Console.Write("{0}\t", value[i, j]);
if (j == columns - 1)
Console.WriteLine("]");
}
}
/// <summary>
/// 在控制台显示矩阵(元素取四位小数)
/// </summary>
public void DisplayLimited()
{
for (int i = 0; i < rows; i++)
for (int j = 0; j < columns; j++)
{
if (j == 0)
Console.Write("[");
Console.Write("{0:f4}\t", value[i, j]);
if (j == columns - 1)
Console.WriteLine("]");
}
}
#endregion
#region 矩阵的运算处理
/// <summary>
/// 返回参数矩阵的对角元素
/// </summary>
/// <param name="x"></param>
/// <returns></returns>
public static double[] Diagonal(Matrix x)//其实是生成对角矩阵方法的反方法,取矩阵的对角元素
{
int num = x.rows > x.columns ? x.columns : x.rows;
double[] result = new double[num];
for (int i = 0; i < num; i++)
{
result[i] = x.value[i, i];
}
return result;
}
/// <summary>
/// 返回参数矩阵的逆矩阵
/// </summary>
/// <param name="x"></param>
/// <returns></returns>
public static Matrix Reverse(Matrix x)
{
if (x.rows != x.columns)
throw new Exception("Reverse函数使用时,求逆的矩阵必须为方阵,行列数必须相同");
if (x.rows == 1)
if (x.value[0, 0] != 0)
{
return new Matrix(1 / x.value[0, 0]);
}
else
throw new Exception("Reverse函数使用时,对数字0求逆错误");
double detVal=Matrix.Det(x);
if (detVal == 0)
throw new Exception("Reverse函数使用时,方阵的行列式为0不可逆");
detVal = 1 / detVal;
return Matrix.CompanionMatrix(x) * detVal;
}
/// <summary>
/// 返回参数矩阵i行j列的余子式
/// </summary>
/// <param name="x">注意必须为方阵</param>
/// <param name="i">i从0起到行数减1</param>
/// <param name="j">j从0起到列数减1</param>
/// <returns></returns>
public static double Cofactor(Matrix x, int i, int j)//求逆的辅助函数,求余子式,注意判断行列数相同
{
double[,] array = new double[x.rows - 1, x.columns - 1];
for (int m = 0; m < x.rows - 1; m++)
{
for (int n = 0; n < x.columns - 1; n++)
{
int s = m, t = n;
if (s >= i)
s++;
if (t >= j)
t++;
array[m, n] = x.value[s, t];
}
}
Matrix cofactor = new Matrix(array);
return Matrix.Det(cofactor);
}
/// <summary>
/// 返回参数矩阵的代数余子式
/// </summary>
/// <param name="x">注意必须为方阵</param>
/// <param name="i">i从0起到行数减1</param>
/// <param name="j">j从0起到列数减1</param>
/// <returns></returns>
public static double AlgeCofactor(Matrix x, int i, int j)//代数余子式
{
return Math.Pow(-1, i + j) * Matrix.Cofactor(x, i, j);
}
/// <summary>
/// 返回参数矩阵的伴随矩阵
/// </summary>
/// <param name="x">注意必须为方阵</param>
/// <returns></returns>
public static Matrix CompanionMatrix(Matrix x)//伴随矩阵
{
double[,] array = new double[x.rows, x.columns];
for (int i = 0; i < x.rows; i++)
{
for (int j = 0; j < x.columns; j++)
{
array[i, j] = Matrix.AlgeCofactor(x, i, j);
}
}
return Matrix.Transfer(new Matrix(array));
}
/// <summary>
/// 返回参数矩阵的转置矩阵
/// </summary>
/// <param name="x"></param>
/// <returns></returns>
public static Matrix Transfer(Matrix x)
{
Matrix result = new Matrix();
result.rows = x.columns;
result.columns = x.rows;
result.value = new double[result.rows, result.columns];
for (int i = 0; i < result.rows; i++)
for (int j = 0; j < result.columns; j++)
result.value[i, j] = x.value[j, i];
return result;
}
/// <summary>
/// 返回参数矩阵的行列式值
/// </summary>
/// <param name="x">注意必须为方阵</param>
/// <returns></returns>
public static double Det(Matrix x)
{
if(x.rows!=x.columns)
throw new Exception("Det函数使用时,矩阵不为方阵不可求行列式");
if (x.rows == 1)
return x.value[0, 0];
if (x.rows == 2)
return x.value[0, 0] * x.value[1, 1] - x.value[0, 1] * x.value[1, 0];
else
{
Matrix temp = new Matrix(x);
temp = Matrix.ToStepMatrix(temp);
double leftup = temp.value[0, 0];
temp = Matrix.SubMatrix(temp, 2, 2, true);
return leftup * Matrix.Det(temp);
}
}
/// <summary>
/// 返回参数矩阵的前i行j列子阵或i行j列后的子阵
/// </summary>
/// <param name="x"></param>
/// <param name="i">i从0起到行数减1</param>
/// <param name="j">j从0起到列数减1</param>
/// <param name="reverse">为true则为取i行j列之后子阵</param>
/// <returns></returns>
public static Matrix SubMatrix(Matrix x, int i, int j, bool reverse = false)
{
Matrix result = new Matrix(x);
if (i > x.rows || j > x.columns)
throw new Exception("SubMatrix函数使用时,子矩阵的行列数超出矩阵行列数,不可求子矩阵");
else
{
if (!reverse)
{
result.rows = i;
result.columns = j;
result.value = new double[i, j];
for (int m = 0; m < i; m++)
for (int n = 0; n < j; n++)
result.value[m, n] = x.value[m, n];
}
else
{
result.rows = x.rows - i+1;
result.columns = x.columns - j + 1;
result.value = new double[result.rows, result.columns];
for (int m = 0; m < result.rows; m++)
for (int n = 0; n < result.columns; n++)
result.value[m, n] = x.value[m + i - 1, n + j - 1];
}
}
return result;
}
/// <summary>
/// 返回参数矩阵转换的阶梯矩阵
/// </summary>
/// <param name="x"></param>
/// <returns></returns>
public static Matrix ToStepMatrix(Matrix x)
{
Matrix result = new Matrix(x);
int[] firstNotZero = new int[result.rows];//记录每一行不为0个数
for (int i = 0; i < result.rows; i++)
{
firstNotZero[i] = 0;
}
for (int i = 0; i < result.rows; i++)
{
for (int j = 0; j < result.columns; j++)
{
if (result.value[i, j] != 0)
{
break;
}
else
{
firstNotZero[i]++;
}
}
}
if (result.rows > 1)//多于1行要排序,将先出现不为0的一行移到上方
{
for (int i = 0; i < result.rows - 1; i++)
{
for (int j = i + 1; j < result.rows; j++)
{
if (firstNotZero[i] > firstNotZero[j])
{
result = Matrix.RowSwitch(result, i, j);
firstNotZero[i] = firstNotZero[i] + firstNotZero[j];//互换
firstNotZero[j] = firstNotZero[i] - firstNotZero[j];
firstNotZero[i] = firstNotZero[i] - firstNotZero[j];
}
}
}
}
if (result.rows > 1)
{
for (int i = 0; i < result.rows - 1; i++)
{
if (firstNotZero[i] >= result.columns)//某一行不出现不为0的数则无需再变,之后每一行均不会再出现非0
break;
for (int j = i + 1; j < result.rows; j++)
{
double mul = -result.value[j, firstNotZero[i]] / result.value[i, firstNotZero[i]];
for (int k = firstNotZero[i]; k < result.columns; k++)
{
result.value[j, k] = result.value[j, k] + mul * result.value[i, k];
}
}
//每一次消完一列都要重新找出每一行第一个不为0的数,因为消列会改变这一值
for (int m = 0; m < result.rows; m++)
{
firstNotZero[m] = 0;
}
for (int m = 0; m < result.rows; m++)
{
for (int n = 0; n < result.columns; n++)
{
if (result.value[m, n] != 0)
{
break;
}
else
{
firstNotZero[m]++;
}
}
}
//
}
}
return result;
}
/// <summary>
/// 返回参数矩阵的元素相乘运算
/// </summary>
/// <param name="x">必须与后一个矩阵同阶</param>
/// <param name="y">必须与前一个矩阵同阶</param>
/// <returns></returns>
public static Matrix DotMultiple(Matrix x, Matrix y)
{
if (x.rows != y.rows || x.columns != y.columns)
throw new Exception("DotMultiple函数使用时,点乘的两矩阵行列数不一致不能点乘");
Matrix result = new Matrix(x);
for (int i = 0; i < result.rows; i++)
{
for (int j = 0; j < result.columns; j++)
{
result.value[i, j] = result.value[i, j] * y.value[i, j];
}
}
return result;
}
/// <summary>
/// 返回参数矩阵的元素相除运算
/// </summary>
/// <param name="x">必须与后一个矩阵同阶</param>
/// <param name="y">必须与前一个矩阵同阶</param>
/// <returns></returns>
public static Matrix DotDevide(Matrix x, Matrix y)
{
if (x.rows != y.rows || x.columns != y.columns)
throw new Exception("DotDevide函数使用时,点除的两矩阵行列数不一致不能点除");
Matrix result = new Matrix(x);
for (int i = 0; i < result.rows; i++)
{
for (int j = 0; j < result.columns; j++)
{
result.value[i, j] = result.value[i, j] / y.value[i, j];
}
}
return result;
}
/// <summary>
/// 返回参数矩阵重组矩阵
/// </summary>
/// <param name="x"></param>
/// <param name="row">重组后的行数</param>
/// <param name="col">重组后的列数</param>
/// <returns></returns>
public static Matrix Reshape(Matrix x, int row, int col)
{
//row*col<x.rows*x.columns则取x的前row*col项重组,否则把x全部取出重组,不够的用0补
Matrix result = new Matrix(row,col);
double[] arrayOfMatrix = Matrix.ToRowVector(x);
if ((row * col) <= (x.rows * x.columns))
{
for (int i = 0; i < row; i++)
{
for (int j = 0; j < col; j++)
{
result.value[i, j] = arrayOfMatrix[i * col + j];
}
}
}
else
{
result = Matrix.Zeros(row, col);
for (int i = 0; i < row; i++)
{
for (int j = 0; j < col; j++)
{
try
{
result.value[i, j] = arrayOfMatrix[i * col + j];
}
catch (IndexOutOfRangeException)
{
//捕捉数组越界错误不进行处理
}
}
}
}
return result;
}