Set option-value pairs on the command line if the default value is not suitable:
Terminal> python decay_argparse.py --I 1.5 --a 2 --dt 0.8 0.4
Code:
def define_command_line_options():
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--I', '--initial_condition', type=float,
default=1.0, help='initial condition, u(0)',
metavar='I')
parser.add_argument('--a', type=float,
default=1.0, help='coefficient in ODE',
metavar='a')
parser.add_argument('--T', '--stop_time', type=float,
default=1.0, help='end time of simulation',
metavar='T')
parser.add_argument('--makeplot', action='store_true',
help='display plot or not')
parser.add_argument('--dt', '--time_step_values', type=float,
default=[1.0], help='time step values',
metavar='dt', nargs='+', dest='dt_values')
return parser
(metavar
is the symbol used in help output)