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# Demonstrate round-off error
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# Matt Bishop, ECS 10, Fall 2012
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# First, set x to 1.0 and print it
x = 0.1
print("This should print the value of x as 0.1:", x)
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# Now, add x to itself 10 times and print the value
y = x + x + x + x + x + x + x + x + x + x
print("This should print 1.0, the value of x added to itself 10 times:", y)
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# Now compare it to 1.0 -- note it's not the same!
print("Now compare y to 1.0:", y == 1.0)
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# And here's why -- go out to 20 decimal places
print("The actual value of y, to 20 places:", "%.20f" % y)