1. Code Name: PEST-I

2. Category: VIIIa. Linear Stability: 2D Ideal

3. Responsible Physicist: J. Manickam

4. Others involved in code development: M. S. Chance, R. L. Dewar, R. C. Grimm, S. C. Jardin, J. Greene, J. Johnson.

5. One line description: Ideal MHD stability analysis of axisymmetric tokamak equilibria.

6. Computer systems which code runs on: NERSC - Cray's, Workstations

7. Typical running time: 1 to 3 min

8. Approximate number of code lines: 20,000

9. Does this code read data files from another code? Uses equilibria calculated by other codes.

10. Does this code produce data files that can be read by another code? Yes, output files read by post-processors.

11. 1-2 paragraph description of code: Linearized stability analysis code based on a minimization of the Lagrangian. Uses a finite element technique. PEST-I solves for all three vector components of the displacement and returns a physical growth-time.

12. Similar codes to this code, and distinguishing differences: NOVA - non- variational approach-PPPL. ERATO - uses a hybrid finite element scheme-Lausanne. GATO - similar to ERATO suited for non up-down symmetric geometry-GA.

13. Journal References describing code (up to 3): 1. Grimm, R. C., Greene, J., and Johnson, J. L. in Meth of Comp. Physics 9 (1976) 253. 2. Grimm, R. C., Dewar, R. L., and Manickam, J., in J. of Comp. Phys. 49 (1983) 94.

14. New code capabilities planned for next 1-2 years: Extension of post- processing capabilities to simulate experimental diagnostics. Integrate with the SeSC equilibrium code.Conversion to NETCDF for universal portability.

15. Code users: PPPL, MIT, Columbia, ORNL, LASL, Hydro-Quebec, LLNL, U. Washington.

16. Present and recent applications of code: Analysis of TFTR and PBX-M. Design studies for NSTX and ITER.

17. Status of code input/output documentation. Check one: ( ) does not exist (X) incomplete ( ) exists

18. Year Code was first used and present frequency of use:1976 - daily

19. Estimate of Man-Years invested in developing code: 4

20. Catagories of usage of Code (Check all that apply): (x ) application code to do analysis and prediction of experiments (x ) numerical testbed of theoretical ideas (x ) physics module to be used in integrated moddelling (x ) code for machine design

21. Language code is writen in: FORTRAN

22. Results of intercomparisons with other codes and results of validation against experiments. Extensively documnented.