### 3D Few Phases Grain Boundary Motion Code

 This is Matlab code, with a C subroutines (mex file), that implements grain boundary motion of networks with arbitrary surface tensions and fixed mobilities, in three space dimensions. Note carefully that the mobility of each interface = 1 / its surface tension, i.e.  ${\mu }_{i,j}=\frac{1}{{\sigma }_{i,j}}$ The algorithm is based on the following paper: Esedoglu, S.; Otto, F. Threshold dynamics for networks with arbitrary surface tensions. Communications on Pure and Applied Mathematics. 68:5 (2015), pp. 808-864. The research that led to this software was supported by the National Science Foundation grant DMS-074333.
 Version 1 December 4, 2015.
 Instructions: After downloading the linked zipped directory, unzip it. For each C source file contained in the directory, issue the command     `mex ls2vf3D.c` from within Matlab. This will compile the auxiliary C routine `ls2vf3D.c` so that it can be called by matlab .m files. The main subroutine is called `td3d.m`. It contains extensive explanations and examples, which can be displayed by issuing the command     `help td3d` in Matlab. Here is an example of how to call the program in Matlab: ```  sampleinitialdata;   clf; showlevelsets(lev0);   lev = td3d(lev0,10,0.001);``` `   clf; showlevelsets(lev);`