Coverage for pySDC/projects/parallelSDC_reloaded/scripts/fig06_allenCahnMPI.py: 95%

1#!/usr/bin/env python3 

2# -*- coding: utf-8 -*- 

3""" 

4Created on Thu Jan 11 11:14:01 2024 

5 

6Figures with experiments on the Allen-Cahn problem (MPI runs) 

7""" 

8import os 

9import sys 

10import json 

11import numpy as np 

12from mpi4py import MPI 

13 

14from pySDC.projects.parallelSDC_reloaded.utils import solutionExact, getParamsSDC, solutionSDC, getParamsRK 

15from pySDC.implementations.sweeper_classes.generic_implicit_MPI import generic_implicit_MPI 

16 

17PATH = '/' + os.path.join(*__file__.split('/')[:-1]) 

18SCRIPT = __file__.split('/')[-1].split('.')[0] 

19 

20COMM_WORLD = MPI.COMM_WORLD 

21 

22# SDC parameters 

23nNodes = 4 

24quadType = 'RADAU-RIGHT' 

25nodeType = 'LEGENDRE' 

26parEfficiency = 0.8 # 1/nNodes 

27nSweeps = 4 

28 

29# Problem parameters 

30pName = "ALLEN-CAHN" 

31tEnd = 50 

32pParams = { 

33 "periodic": False, 

34 "nvars": 2**11 - 1, 

35 "epsilon": 0.04, 

36} 

37 

38# ----------------------------------------------------------------------------- 

39# %% Convergence and error VS cost plots 

40# ----------------------------------------------------------------------------- 

41nStepsList = np.array([5, 10, 20, 50, 100, 200, 500]) 

42dtVals = tEnd / nStepsList 

43 

44 

45def getError(uNum, uRef): 

46 if uNum is None: 

47 return np.inf 

48 return np.linalg.norm(uRef[-1, :] - uNum[-1, :], ord=2) 

49 

50 

51def getCost(counters): 

52 _, _, tComp = counters 

53 return tComp 

54 

55 

56try: 

57 qDelta = sys.argv[1] 

58 if qDelta.startswith("--"): 

59 qDelta = "MIN-SR-FLEX" 

60except IndexError: 

61 qDelta = "MIN-SR-FLEX" 

62 

63try: 

64 params = getParamsRK(qDelta) 

65except KeyError: 

66 params = getParamsSDC(quadType=quadType, numNodes=nNodes, nodeType=nodeType, qDeltaI=qDelta, nSweeps=nSweeps) 

67 

68useMPI = False 

69if COMM_WORLD.Get_size() == 4 and qDelta in ["MIN-SR-NS", "MIN-SR-S", "MIN-SR-FLEX", "VDHS"]: # pragma: no cover 

70 params['sweeper_class'] = generic_implicit_MPI 

71 useMPI = True 

72 

73errors = [] 

74costs = [] 

75 

76root = COMM_WORLD.Get_rank() == 0 

77if root: 

78 print(f"Running simulation with {qDelta}") 

79 

80for nSteps in nStepsList: 

81 if root: 

82 uRef = solutionExact(tEnd, nSteps, pName, **pParams) 

83 

84 uSDC, counters, parallel = solutionSDC(tEnd, nSteps, params, pName, verbose=root, noExcept=True, **pParams) 

85 

86 if root: 

87 err = getError(uSDC, uRef) 

88 errors.append(err) 

89 

90 cost = getCost(counters) 

91 costs.append(cost) 

92 

93if COMM_WORLD.Get_rank() == 0: 

94 errors = [float(e) for e in errors] 

95 

96 print("errors : ", errors) 

97 print("tComps : ", costs) 

98 fileName = f"{PATH}/fig06_compTime.json" 

99 timings = {} 

100 if os.path.isfile(fileName): 

101 with open(fileName, "r") as f: 

102 timings = json.load(f) 

103 

104 timings[qDelta + "_MPI" * useMPI] = {"errors": errors, "costs": costs} 

105 

106 with open(fileName, 'w') as f: 

107 json.dump(timings, f, indent=4)