import sys, math
args = len(sys.argv)
if ((args < 2) or (args > 3)):
        print('Please enter either 1 or 2 numerical command line arguments')
if (len(sys.argv)==2):
	num=eval(sys.argv[-1])
	print('The log of ', num,' (to base e) is ',math.log(num))
elif (len(sys.argv)==3):
	num=eval(sys.argv[-1])
	base=eval(sys.argv[-2])
	print('The log of ', num,' (to base ', base,') is ',math.log(num,base))