How to use GNM:
1. Remove excess on PDB file (only keep rows that are labeled "ATOM")

2. Copy those rows into Excel file with headings:

Atom	Number	Unknown	Chain	Unknown	x	y	z	Unknown

3. Save as .xls/.xlsx file

4. Import file into matlab code titled "fluctuations"

5. Create ANOTHER Excel file with headings:

Node #	x	y	z	Fluctuation

6. Copy node # and x,y and z positions from Excel file in step 2.

7. Copy MATLAB results into the fluctuation column of Excel file in step 5. 

8. Import Excel file from step 5 into MATLAB code titled "colorgraph: