单边裂纹梁的前四阶频率计算，完成以后进行系数的计算，然后得到振型，并画出图片-Unilateral cracked beam of the first four frequency bands calculated after the completion of the coefficient calculation, and then get mode shapes, and draw pictures

断裂资料，对于初学者来说很有用。裂纹扩展的例子，手把手教-Fracture data, useful for beginners. Examples of crack propagation, Shoubashoujiao