Floating Point Approximations.

Here's another example of floating point errors, that's even simpler than
the 21200 plus 2.5% example.

int i;
float x = 0;
for (i = 1; i < 100; ++i)
x += 0.01;
x -= 1;
printf (x);

I apologize if I copied the code wrong. The idea is to start with zero,
add one hundredth a hundred times, and subtract one. The answer is not
quite zero.



Many environments will give a small error. This is such a trivial example
that it should make all programmers shudder about using floats, unless they
really know what they are doing.




.

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