Cornell University

Department of Physics

Phys 480/680, Astro 690 April 14, 2000

Computational Physics, Spring 2000

LargeHomework Assignment # 9

(Due Thursday, April 20 at 8:40 am in Lab.)

Agenda and readings for the remainder of the term

All readings from Numerical Recipes: The Art of Scientific Computing, 2 edition (in Fortran or C).

• • Lab7/HW#8, 04/13: Inner loop optimization; blocking.
• • Lec13, 04/11: Use of discrete Fourier Transform (DFT) to solve Poisson's equation
  • Lab8/HW#9, 04/20: Solution of Poisson's equation in multiple dimensions
• • Lec14, 04/18: Schrödinger's equation in multiple dimensions; conjugate-gradient minimization Reading: 10.0-10.6;
  • Lab9/HW#10, 04/27: Schrödinger's equation in multiple dimensions
• • Lec15, 04/25: Kohn-Sham equations in multiple dimensions
  • Lab10/HW#11, 05/04: DFT solutions of molecules
• • Lec16, 05/02: Tie up any loose-ends

Goals for this assignment: Solution of Poisson's equation in d=3 using the FFT; learn to use overloading to express scientific algorithms succinctly; solution of Poisson's equation in a single line of code:

  phiG=I(Linv((-4*pi)*O(J(rho))));

• Contents
• Infrastructure
  • Working with classes
    • Using classes in the standard C++ library
    • Working with user defined classes: ``vec.C''
  • ``pvector'' class
    • C3tensor() and free_C3tensor()
      • Debugging
    • sum()
    • operator-(), operator*()
    • I()
    • J()
    • O() and Linv()
• Physics
  • evalr()
    • Debugging
  • Potential from a sum of two Gaussian distributions
    • GaussR()
      • Debugging:
    • Computation of total electrostatic potential energy U
      • Debugging:
    • Computation of potential field
      • For fun:
      • Challenge physics question:
• ``complex.C''
• ``vec.C''
• ``pvector.C''
• main() for ``physics.C''
• About this document ...

Postscript Version

PDF Version