def solve(positions, num_trials):
"""
For a given position list and number of trials, run the experiments
and draw the plots.
"""
for position in positions:
# create a new class
investment = Investment(position)
daily_ret = []
for trial in range(num_trials):
# do a invest each time
investment.invest()
# calculate the corresponding daily_ret, using double
daily_ret.append(investment.ret * 1.0 / 1000.0 - 1.0)
print("The mean of position", position, "is", mean(daily_ret))
print("The standard deviation of position", position, "is",
stdev(daily_ret))
plt.hist(daily_ret, 100, range=[-1, 1])
plt.show()
