The project aims to calculate the self-resonant frequency (SRF) of irregular solenoids. The details of the algorithm can be found in the paper W. Zhou, and S. Y. Huang, "An Accurate Model for Fast Calculating the Resonant Frequency of an Irregular Solenoid", IEEE Transactions on Microwave Theory and Techniques. The functions for calculating the SRF of cylindrical solenoids with uniform pitches, cylindrical solenoids with varied pitches, and spherical solenoids are in the files "func_SRF_calculation_cylindrical.m", "func_SRF_calculation_cylindrical_varied_pitch.m", and "func_SRF_calculation_spherical.m", respectively. "calculateB" is a function for calculating magnetic field with Biot-Savart Law. It is called by all the other three functions.