[Pull Request] Added a set of functions, Removed some files.

Common.BasicHelper/Math/Equation.cs

@@ -0,0 +1,122 @@
+namespace Common.BasicHelper.Math;
+
+public class Equation
+{
+    /// <summary>
+    /// 解方程 - 二元一次
+    /// </summary>
+    /// <param name="a1">方程一的系数 a</param>
+    /// <param name="b1">方程一的系数 b</param>
+    /// <param name="c1">方程一的结果 c</param>
+    /// <param name="a2">方程二的系数 a</param>
+    /// <param name="b2">方程二的系数 b</param>
+    /// <param name="c2">方程二的系数 c</param>
+    /// <returns>结果 - x，y - 组成的数组</returns>
+    public static double[] SolveEquation(
+        double a1, double b1, double c1,
+        double a2, double b2, double c2)
+    {
+        var rst = new double[2];
+        rst[1] = (c2 - (a2 * c1 / a1)) / (b2 - (a2 * b1 / a1));
+        rst[0] = (c1 - (b1 * rst[1])) / a1;
+        return rst;
+    }
+
+    /// <summary>
+    /// 解方程 - 三元一次
+    /// </summary>
+    /// <param name="a1">方程一的系数 a</param>
+    /// <param name="b1">方程一的系数 b</param>
+    /// <param name="c1">方程一的系数 c</param>
+    /// <param name="d1">方程一的结果 d</param>
+    /// <param name="a2">方程二的系数 a</param>
+    /// <param name="b2">方程二的系数 b</param>
+    /// <param name="c2">方程二的系数 c</param>
+    /// <param name="d2">方程二的结果 d</param>
+    /// <returns>结果 - x，y - 组成的数组</returns>
+    public static double[] SolveEquation(
+        double a1, double b1, double c1, double d1,
+        double a2, double b2, double c2, double d2,
+        double a3, double b3, double c3, double d3
+        )
+    {
+        var rst = new double[3];
+        double na1, nb1, nc1, na2, nb2, nc2, x, y, z;
+
+        na1 = a1 * b2 - a2 * b1; nb1 = a1 * c2 - a2 * c1; nc1 = a1 * d2 - a2 * d1;
+
+        na2 = a1 * b3 - a3 * b1; nb2 = a1 * c3 - a3 * c1; nc2 = a1 * d3 - a3 * d1;
+
+        var y_z = SolveEquation(na1, nb1, nc1, na2, nb2, nc2);
+        y = y_z[0]; z = y_z[1];
+        x = (d1 - b1 * y - c1 * z) / a1;
+        rst[0] = x; rst[1] = y; rst[2] = z;
+        return rst;
+    }
+
+    /* a1x+b1y+c1z+d1m=e1
+     * a2x+b2y+c2z+d2m=e2
+     * a3x+b3y+c3z+d3m=e3
+     * a4x+b4y+c4z+d4m=e4
+     * 
+     * a1x=e1-b1y-c1z-d1m
+     * x=(e1-b1y-c1z-d1m)/a1
+     * 
+     * a2(e1-b1y-c1z-d1m)/a1+b2y+c2z+d2m=e2
+     * a3(e1-b1y-c1z-d1m)/a1+b3y+c3z+d3m=e3
+     * a4(e1-b1y-c1z-d1m)/a1+b4y+c4z+d4m=e4
+     * 
+     * (a1*b2-a2*b1)y+(a1*c2-a2*c1)z+(a1*d2-a2*d1)m=a1*e2-a2*e1
+     * (a1*b3-a3*b1)y+(a1*c3-a3*c1)z+(a1*d3-a3*d1)m=a1*e3-a3*e1
+     * (a1*b4-a4*b1)y+(a1*c4-a4*c1)z+(a1*d4-a4*d1)m=a1*e4-a4*e1
+     */
+
+    /// <summary>
+    /// 解方程组 - 四元一次
+    /// </summary>
+    /// <param name="a1">方程一的系数 a</param>
+    /// <param name="b1">方程一的系数 b</param>
+    /// <param name="c1">方程一的系数 c</param>
+    /// <param name="d1">方程一的系数 d</param>
+    /// <param name="e1">方程一的结果 e</param>
+    /// <param name="a2">方程二的系数 a</param>
+    /// <param name="b2">方程二的系数 b</param>
+    /// <param name="c2">方程二的系数 c</param>
+    /// <param name="d2">方程二的系数 d</param>
+    /// <param name="e2">方程二的结果 e</param>
+    /// <param name="a3">方程三的系数 a</param>
+    /// <param name="b3">方程三的系数 b</param>
+    /// <param name="c3">方程三的系数 c</param>
+    /// <param name="d3">方程三的系数 d</param>
+    /// <param name="e3">方程三的结果 e</param>
+    /// <param name="a4">方程四的系数 a</param>
+    /// <param name="b4">方程四的系数 b</param>
+    /// <param name="c4">方程四的系数 c</param>
+    /// <param name="d4">方程四的系数 d</param>
+    /// <param name="e4">方程四的结果 e</param>
+    /// <returns>x_y_z_t 的数组，对应角标分别为 0,1,2,3</returns>
+    public static double[] SolveEquation(
+        double a1, double b1, double c1, double d1, double e1,
+        double a2, double b2, double c2, double d2, double e2,
+        double a3, double b3, double c3, double d3, double e3,
+        double a4, double b4, double c4, double d4, double e4
+        )
+    {
+        var rst = new double[4];
+        double na1, nb1, nc1, nd1, na2, nb2, nc2, nd2, na3, nb3, nc3, nd3, x, y, z, m;
+        na1 = a1 * b2 - a2 * b1; nb1 = a1 * c2 - a2 * c1;
+        nc1 = a1 * d2 - a2 * d1; nd1 = a1 * e2 - a2 * e1;
+        na2 = a1 * b3 - a3 * b1; nb2 = a1 * c3 - a3 * c1;
+        nc2 = a1 * d3 - a3 * d1; nd2 = a1 * e3 - a3 * e1;
+        na3 = a1 * b4 - a4 * b1; nb3 = a1 * c4 - a4 * c1;
+        nc3 = a1 * d4 - a4 * d1; nd3 = a1 * e4 - a4 * e1;
+        var y_z_m = SolveEquation(
+            na1, nb1, nc1, nd1,
+            na2, nb2, nc2, nd2,
+            na3, nb3, nc3, nd3);
+        y = y_z_m[0]; z = y_z_m[1]; m = y_z_m[2];
+        x = (e1 - b1 * y - c1 * z - d1 * m) / a1;
+        rst[0] = x; rst[1] = y; rst[2] = z; rst[3] = m;
+        return rst;
+    }
+}

Common.BasicHelper/Math/Standard.cs

@@ -53,4 +53,19 @@ public static T Max<T>(params T[] input) where T : IComparable<T>
 
         return max;
     }
+
+    /// <summary>
+    /// 获取指定位数的数字
+    /// 例如：456 取 2 位数返回 5，6892 取 4 位数返回 6
+    /// </summary>
+    /// <param name="number">指示要被获取指定位数字的数字</param>
+    /// <param name="bit">指示要获取的位数</param>
+    /// <returns>返回指定位上数字</returns>
+    public static int GetBit(int number, int bit)
+    {
+        var pow = 10;
+        for (var i = 0; i < bit - 1; ++i)
+            pow *= pow;
+        return (number % pow) / (pow / 10);
+    }
 }

Common.BasicHelper/Math/Tricks.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Common.BasicHelper.Math;
+
+public class Tricks
+{
+    /// <summary>
+    /// 获取一个乘法表
+    /// </summary>
+    /// <param name="from">乘法表从哪开始</param>
+    /// <param name="to">乘法表从哪结束</param>
+    /// <param name="direction">方向, true 为正三角, false 为反三角, 默认为正</param>
+    /// <returns>一个分行的乘法表</returns>
+    public static string GetMultiplicationTable(int from, int to, bool direction = true)
+    {
+        var sb = new StringBuilder();
+
+        if (direction)
+        {
+            for (var x = from; x <= to; ++x)
+            {
+                for (var y = from; y <= x; ++y)
+                    sb.Append($"{y}*{x}={x * y}\t");
+                sb.AppendLine();
+            }
+        }
+        else
+        {
+            for (var x = from; x >= from; --x)
+            {
+                for (var y = from; y <= x; ++y)
+                    sb.Append($"{y}*{x}={x * y}\t");
+                sb.AppendLine();
+            }
+        }
+
+        return sb.ToString();
+    }
+}
+
+public static class TricksExtensions
+{
+    /// <summary>
+    /// 获取一个乘法表
+    /// </summary>
+    /// <param name="from">乘法表从哪开始</param>
+    /// <param name="to">乘法表从哪结束</param>
+    /// <param name="direction">方向, true 为正三角, false 为反三角, 默认为正</param>
+    /// <returns>一个分行的乘法表</returns>
+    public static string GetMultiplicationTableTo(this int from, int to, bool direction = true)
+        => Tricks.GetMultiplicationTable(from, to, direction);
+}

Common.BasicHelper/Util/Extension/CleanHelper.cs

@@ -6,7 +6,6 @@ namespace Common.BasicHelper.Util.Extension;
 
 public static class CleanHelper
 {
-
     /// <summary>
     /// 关闭并释放对象
     /// </summary>