This is the readme for the model associated with the papers: Lee SG, Kim S (2006) Bifurcation analysis of mode-locking structure in a Hodgkin-Huxley neuron under sinusoidal current. Phys Rev E Stat Nonlin Soft Matter Phys 73:041924 Gangal et al., under preparation. To run the code, follow these simple guidelines: 1) Unzip this archive and change directory to the new HHNeuron folder 2) compile any or each C file (most unix systems allow you to just type a command like): make c_file_name_without_the_dot_c_on_the_end which should compile the C language file. 3) You will be able to run the C codes now with a command like ./c_file_name_without_the_dot_c_on_the_end 4) after a short time (less than a minute) data files will appear that you can analyze with your favorite graphing program. File Utilities : a) HHneuron_27June2013.c This file solves the 4 parameters differential equations according to Runge Kutta 4th order method , and generates text files with Voltage , Current , gate probabilities etc . Using thesis you can generate action potential figures and find the gate probability information for any input external current b) Poincaremap_9thJuly2013.c This is a mathematical tool that we used to find periodicity in the system . Application of non linear dynamics to data analysis and physical systems . c) SpikeStatistics4thJulynight.c This code returns the repeating spiking sequences in the output voltages , and also the mode locking ratios of the O/P vs I/P in terms of their frequencies d) par_diag.h , par_HH.h We used the input to be sinusoidal , hence through the .h files we specify the input frequency and the amplitude . You can also set a range of frequencies or amplitudes or both . To provide a constant input you just need to set the frequency to 0 and give the desired amplitude . You can also modify the input to anything you want Except the input current , the h files contains information of the simulation time , delta frequency , delta amplitude etc For any query on intricate functionality and bug reports , please mail to himanshugangalcoursera@gmail.com