中文说明：
一个等温边界条件下计算墙角内温度场的小程序，用户输入墙角两侧温度，墙体热导率，设定网格尺寸后程序便会自动迭代求解并同时以矩阵和三维图形的形式输出运算结果。
English Description：
A small program for calculating the temperature field in the corner under isothermal boundary conditions. The user inputs the temperature on both sides of the corner and the thermal conductivity of the wall. After setting the grid size, the program will automatically solve the problem iteratively, and output the calculation results in the form of matrix and three-dimensional graphics at the same time