Walker: Integrating the Ornstein-Uhlenbeck SDE
This example runs Walker to integrate the Ornstein-Uhlenbeck SDE (see DiffEq/OrnsteinUhlenbeck.h) using constant coefficients.
Control file
title "Example problem" walker #nstep 1 # Max number of time steps term 5.0 # Max time dt 0.001 # Time step size npar 1000000 # Number of particles (this many only to have a reasonably # smooth bivariated PDF ttyi 1000 # TTY output interval rngs mkl_mrg32k3a seed 0 end end ornstein-uhlenbeck depvar r init raw coeff const ncomp 3 theta 1.0 2.0 3.0 end mu 0.0 0.5 1.0 end # Upper triangle of the square of the diffusion matrix 'sigma-square'. # Must be symmetric positive semi-definite. sigmasq 4.0 2.5 1.1 32.0 5.6 23.0 end rng mkl_mrg32k3a end statistics interval 2 <R> <rr> <R2> <r2r2> <R3> <r3r3> <r1r2> <r1r3> <r2r3> end pdfs interval 1000 filetype gmshbin policy overwrite centering node #format scientific #precision 4 f2( r1 r2 : 2.0e-1 2.0e-1 ) #; -2 2 -2 2 ) end end
Example run on 4 CPUs
./charmrun +p4 Main/walker -v -c ../../tmp/ou.q -u 0.9
Output
Running on 4 processors: Main/walker -v -c ../../tmp/ou.q -u 0.9 charmrun> /usr/bin/setarch x86_64 -R mpirun -np 4 Main/walker -v -c ../../tmp/ou.q -u 0.9 Charm++> Running on MPI version: 3.0 Charm++> level of thread support used: MPI_THREAD_SINGLE (desired: MPI_THREAD_SINGLE) Charm++> Running in non-SMP mode: numPes 4 Converse/Charm++ Commit ID: b8b2735 CharmLB> Load balancer assumes all CPUs are same. Charm++> Running on 1 unique compute nodes (4-way SMP). Charm++> cpu topology info is gathered in 0.000 seconds. ,::,` `. .;;;'';;;: ;;# ;;;@+ +;;; ;;;;;, ;;;;. ;;;;;, ;;;; ;;;; `;;;;;;: ;;; :;;@` :;;' .;;;@, ,;@, ,;;;@: .;;;' .;+;. ;;;@#:';;; ;;;;' ;;;# ;;;: ;;;' ;: ;;;' ;;;;; ;# ;;;@ ;;; ;+;;' .;;+ ;;;# ;;;' ;: ;;;' ;#;;;` ;# ;;@ `;;+ .;#;;;. ;;;# :;;' ;;;' ;: ;;;' ;# ;;; ;# ;;;@ ;;; ;# ;;;+ ;;;# .;;; ;;;' ;: ;;;' ;# ,;;; ;# ;;;# ;;;: ;@ ;;; ;;;# .;;' ;;;' ;: ;;;' ;# ;;;; ;# ;;;' ;;;+ ;', ;;;@ ;;;+ ,;;+ ;;;' ;: ;;;' ;# ;;;' ;# ;;;' ;;;' ;':::;;;; `;;; ;;;@ ;;;' ;: ;;;' ;# ;;;';# ;;;@ ;;;:,;+++++;;;' ;;;; ;;;@ ;;;# .;. ;;;' ;# ;;;;# `;;+ ;;# ;# ;;;' .;;; :;;@ ,;;+ ;+ ;;;' ;# ;;;# ;;; ;;;@ ;@ ;;;. ';;; ;;;@, ;;;;``.;;@ ;;;' ;+ .;;# ;;; :;;@ ;;; ;;;+ :;;;;;;;+@` ';;;;;'@ ;;;;;, ;;;; ;;+ +;;;;;;#@ ;;;;. .;;;;;; .;;#@' `#@@@: ;::::; ;:::: ;@ '@@@+ ;:::; ;:::::: :;;;;;;. __ __ .__ __ .;@+@';;;;;;' / \ / \_____ | | | | __ ___________ ` '#''@` \ \/\/ /\__ \ | | | |/ // __ \_ __ \ \ / / __ \| |_| <\ ___/| | \/ \__/\ / (____ /____/__|_ \\___ >__| \/ \/ \/ \/ < ENVIRONMENT > ------ o ------ * Build environment: -------------------- Hostname : sprout Executable : walker Version : 0.1 Release : LA-CC-XX-XXX Revision : e26d8f8514a11ade687ba460f42dfae5af53d4d6 CMake build type : DEBUG Asserts : on (turn off: CMAKE_BUILD_TYPE=RELEASE) Exception trace : on (turn off: CMAKE_BUILD_TYPE=RELEASE) MPI C++ wrapper : /opt/openmpi/1.8/clang/system/bin/mpicxx Underlying C++ compiler : /usr/bin/clang++-3.5 Build date : Fri Feb 6 06:39:01 MST 2015 * Run-time environment: ----------------------- Date, time : Sat Feb 7 11:58:53 2015 Work directory : /home/jbakosi/code/quinoa/build/clang Executable (rel. to work dir) : Main/walker Command line arguments : '-v -c ../../tmp/ou.q -u 0.9' Output : verbose (quiet: omit -v) Control file : ../../tmp/ou.q Parsed control file : success < FACTORY > ---- o ---- * Particle properties data layout policy (CMake: LAYOUT): --------------------------------------------------------- particle-major * Registered differential equations: ------------------------------------ Unique equation types : 8 With all policy combinations : 18 Legend: equation name : supported policies Policy codes: * i: initialization policy: R-raw, Z-zero * c: coefficients policy: C-const, J-jrrj Beta : i:RZ, c:CJ Diagonal Ornstein-Uhlenbeck : i:RZ, c:C Dirichlet : i:RZ, c:C Gamma : i:RZ, c:C Generalized Dirichlet : i:RZ, c:C Ornstein-Uhlenbeck : i:RZ, c:C Skew-Normal : i:RZ, c:C Wright-Fisher : i:RZ, c:C < PROBLEM > ---- o ---- * Title: Example problem ------------------------ * Differential equations integrated (1): ---------------------------------------- < Ornstein-Uhlenbeck > kind : stochastic dependent variable : r initialization policy : R coefficients policy : C start offset in particle array : 0 number of components : 3 random number generator : MKL MRG32K3A coeff sigmasq [6, upper tri] : { 4 2.5 1.1 32 5.6 23 } coeff theta [3] : { 1 2 3 } coeff mu [3] : { 0 0.5 1 } * Output filenames: ------------------- Statistics : stat.txt PDF : pdf * Discretization parameters: ---------------------------- Number of time steps : 18446744073709551615 Terminate time : 5 Initial time step size : 0.001 * Output intervals: ------------------- TTY : 1000 Statistics : 2 PDF : 1000 * Statistical moments and distributions: ---------------------------------------- Estimated statistical moments : <R1> <R2> <R3> <r1r1> <r1r2> <r1r3> <r2r2> <r2r3> <r3r3> PDFs : f2(r1,r2:0.2,0.2) PDF output file type : gmshbin PDF output file policy : overwrite PDF output file centering : node Text floating-point format : default Text precision in digits : 6 * Load distribution: -------------------- Virtualization [0.0...1.0] : 0.9 Load (number of particles) : 1000000 Number of processing elements : 4 Number of work units : 40 (39*25000+25000) * Time integration: Differential equations testbed -------------------------------------------------- Legend: it - iteration count t - time dt - time step size ETE - estimated time elapsed (h:m:s) ETA - estimated time for accomplishment (h:m:s) out - output-saved flags (S: statistics, P: PDFs) it t dt ETE ETA out --------------------------------------------------------------- 1000 1.000000e+00 1.000000e-03 000:04:16 000:17:04 SP 2000 2.000000e+00 1.000000e-03 000:08:33 000:12:49 SP 3000 3.000000e+00 1.000000e-03 000:12:51 000:08:34 SP 4000 4.000000e+00 1.000000e-03 000:17:06 000:04:16 SP 5000 5.000000e+00 1.000000e-03 000:21:19 000:00:00 SP Normal finish, maximum time reached: 5.000000 * Timers (h:m:s): ----------------- Initial conditions : 0:0:0 Migration of global-scope data : 0:0:0 Total runtime : 0:21:19 [Partition 0][Node 0] End of program
Estimated moments
Left – time evolution of the means and the means of the invariant distribution, right – time evolution of the components of the covariance matrix and those of the invariant.
Gnuplot commands to reproduce the above plots:
plot "stat.txt" u 2:3 w l t "<R1>", "stat.txt" u 2:4 w l t "<R2>", "stat.txt" u 2:5 w l t "<R3>", 0 lt 1, 0.5 lt 2, 1.0 lt 3 plot "stat.txt" u 2:6 w l t "<r1r1>", "stat.txt" u 2:7 w l t "<r1r2>", "stat.txt" u 2:8 w l t "<r1r3>", "stat.txt" u 2:9 w l t "<r2r2>", "stat.txt" u 2:10 w l t "<r2r3>", "stat.txt" u 2:11 w l t "<r3r3>", 4.0/2 lt 1, 2.5/3 lt 2, 1.1/4 lt 3, 32.0/4 lt 4, 5.6/5 lt 5, 23.0/6 lt 6
Estimated bivariate PDF
Example visualization of the estimated bivariate PDF at the final time step using gmsh.