#!/usr/bin/env python

# import required modules
#
import os
import sys
import numpy as np

# a simple function
#
def add0(x, y):
    z = x + y
    return z

# a more intesting function
#
def add1(x = -1, y = -99):
    z = x + y
    return z

# a more intesting function
#
def add2(x = -1, y = -1):
    z = x + y
    return x, y, z

# a more intesting function
#
def myresize(ml, str):
    ml.append(str)
    return ml

# main: this is the main function of this Python
#
def main(argv):

    # call the simple version
    #
    value = add0(float(1.0), float(2.0))
    print("value = ", value)
            
    # call the simple version with command line values
    #
    value = add0(float(sys.argv[1]), float(sys.argv[2]))
    print("value = ", value)

    # call the simple version with command line values
    #
    value = add1()
    print("value = ", value)

    # call the simple version with command line values
    #
    value = add1(y = 2, x = 3)
    print("value = ", value)

    # call the simple version with command line values
    #
    value = add1(y = 12345)
    print("value = ", value)

    # call the simple version with command line values
    #
    a, b, c = add2(y = 1, x = -1)
    _, _, value = add2(y = 1, x = -1)
    print("value = ", value)
    arg1, _, value = add2(y = 1, x = -1)
    print("arg1 = %f" % (arg1), "value = %f" % (value))

    # dynamic memory allocation
    #
    mylist = ["one", "two", "three"]
    print("Before: ", mylist)
    myresize(mylist, "four")
    print("After: ", mylist)

    print("-------------")
    # matrices
    #
    v1 = np.array([1.5, 2.25, 3.1111], np.float32)
    print(v1)

    v2 = np.array([3.0, 2.0, 1.0], np.float32)
    print(v2)

    v3 = v1 + v2
    print(v3)

    vi = np.array([8, 9, 10], np.int32)
    print(vi)
    print("Sum: ", vi + v1)

    m4 = [[1], [1, 2], [1, 2, 3]]
    print(m4)

    m5 = np.array([[1, 0, 0], [0, 1, 0], [0, 0, 1]], np.float32)
    print(m5)

    m6 = m5 + m5
    print(m6)

    # exit gracefully
    #
    return 0

# begin gracefully
#
if __name__ == "__main__":
    main(sys.argv)

#
# end of file