Script to plot some Amdahl's law curves.

amdahl.py

# Copyright (c) 2015 Radovan Bast
# Licensed under the MIT license - http://opensource.org/licenses/MIT


from pylab import *


def get_amdahl(p, n):
    s = 1.0/((1.0 - p) + (p/n))
    return s


def get_function(p, num_elements):
    return map(get_amdahl, [p]*num_elements, range(1, num_elements+1))


m = 60

plot(get_function(1.00, m), label='ideal', linewidth=2.0)
plot(get_function(0.99, m), label='99%',   linewidth=2.0)
plot(get_function(0.90, m), label='90%',   linewidth=2.0)
plot(get_function(0.75, m), label='75%',   linewidth=2.0)
plot(get_function(0.50, m), label='50%',   linewidth=2.0)

grid(True)
ylabel("Speedup")
xlabel("Number of processes")
legend()
savefig("amdahl.png", dpi=72)