# [Tutor] Need to write a python and call it within a python main program

Kermit Rose kermit at polaris.net
Sat Feb 18 04:09:05 CET 2006

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I need to write a function that modifies its 4 imput values,
a,b,c,d according to the following rules.

set j = 8 * mod(a,2) + 4 * mod(b,2) + 2 * mod(c,2) + mod(d,2)

if j = 0,  a,b,c,d = a/2,b/2,c/2,d/2
if j = 1,  a,b,c,d = -1,-1,-1,-1
if j = 2,  a,b,c,d = a,b/2,c,d/2
if j = 3,  a,b,c,d = a,(a+b)/2,c,(d-c)/2
if j = 4,  a,b,c,d = a,b,c/2,d/2
if j = 5,  a,b,c,d = a,b,(a+c)/2,(d-b)/2
if j = 6,  a,b,c,d = b,a,d,c
if j = 7,  a,b,c,d = b,a,d,c
if j = 8,  a,b,c,d = -1,-1,-1,-1
if j = 9,  a,b,c,d = 2*a,a+b,a+c,(d-a-b-c)/2
if j = 10, a,b,c,d = b,a,d,c
if j = 11, a,b,c,d = 2*a,a+b,c,(d-c)/2
if j = 12, a,b,c,d = b,a,d,c
if j = 13, a,b,c,d = 2*a,b,a+c,(d-b)/2
if j = 14, a,b,c,d = b,a,d,c
if j = 15, a,b,c,d = a,a+b,a+c,d-a-b-c

I also need to find out how to write the main program that calls this
function repeatedly, testing
the output values for the solution to the equation.

Kermit   <         kermit at polaris.net    >

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