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""" 

8 

9import os 

10import sys 

11import json 

12import numpy as np 

13from mpi4py import MPI 

14 

15from pySDC.projects.parallelSDC_reloaded.utils import solutionExact, getParamsSDC, solutionSDC, getParamsRK 

16from pySDC.implementations.sweeper_classes.generic_implicit_MPI import generic_implicit_MPI 

17 

18PATH = '/' + os.path.join(*__file__.split('/')[:-1]) 

19SCRIPT = __file__.split('/')[-1].split('.')[0] 

20 

21COMM_WORLD = MPI.COMM_WORLD 

22 

23# SDC parameters 

24nNodes = 4 

25quadType = 'RADAU-RIGHT' 

26nodeType = 'LEGENDRE' 

27parEfficiency = 0.8 # 1/nNodes 

28nSweeps = 4 

29 

30# Problem parameters 

31pName = "ALLEN-CAHN" 

32tEnd = 50 

33pParams = { 

34 "periodic": False, 

35 "nvars": 2**11 - 1, 

36 "epsilon": 0.04, 

37} 

38 

39# ----------------------------------------------------------------------------- 

40# %% Convergence and error VS cost plots 

41# ----------------------------------------------------------------------------- 

42nStepsList = np.array([5, 10, 20, 50, 100, 200, 500]) 

43dtVals = tEnd / nStepsList 

44 

45 

46def getError(uNum, uRef): 

47 if uNum is None: 

48 return np.inf 

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

50 

51 

52def getCost(counters): 

53 _, _, tComp = counters 

54 return tComp 

55 

56 

57try: 

58 qDelta = sys.argv[1] 

59 if qDelta.startswith("--"): 

60 qDelta = "MIN-SR-FLEX" 

61except IndexError: 

62 qDelta = "MIN-SR-FLEX" 

63 

64try: 

65 params = getParamsRK(qDelta) 

66except KeyError: 

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

68 

69useMPI = False 

70if COMM_WORLD.Get_size() == 4 and qDelta in ["MIN-SR-NS", "MIN-SR-S", "MIN-SR-FLEX", "VDHS"]: # pragma: no cover 

71 params['sweeper_class'] = generic_implicit_MPI 

72 useMPI = True 

73 

74errors = [] 

75costs = [] 

76 

77root = COMM_WORLD.Get_rank() == 0 

78if root: 

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

80 

81for nSteps in nStepsList: 

82 if root: 

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

84 

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

86 

87 if root: 

88 err = getError(uSDC, uRef) 

89 errors.append(err) 

90 

91 cost = getCost(counters) 

92 costs.append(cost) 

93 

94if COMM_WORLD.Get_rank() == 0: 

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

96 

97 print("errors : ", errors) 

98 print("tComps : ", costs) 

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

100 timings = {} 

101 if os.path.isfile(fileName): 

102 with open(fileName, "r") as f: 

103 timings = json.load(f) 

104 

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

106 

107 with open(fileName, 'w') as f: 

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