Strange round behavior

[Duane Nykamp]

Is this the intended result of rounding to one decimal place?  Sympy needs to go back to school on rounding. :)

In [13]: S(0.06).round(1)
Out[13]: 0.e-1

[Aaron Meurer]

I think it's a bug with the printer. S(0.06).round(1) == 0.1 gives
True. Can you open an issue for it?

Aaron Meurer

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[Chris Smith]

I think it's a corner case in terms of how the result is given precision. It's off by 1 in this case. And being off by one doesn't affect the boolean:

```

>>> Float('.1',0)==.1

True

>>> Float('.1',1)==.1

True

```

[Chris Smith]

It should work now in the most recent build. Thanks for reporting the issue.

[Duane Nykamp]

Thanks for fixing this!

[Duane Nykamp]

More strange round behavior, this time with negative numbers.

In [1]: S(123.6).round(0)
Out[1]: 124.

In [2]: S(-123.6).round(0)
Out[2]: -123.

In [3]: S(-123.7).round(0)
Out[3]: -124.

The rounding up behavior seems to occur between 6 and 7.  This isn't a precision/binary representation issue as the break is occurring far away from the correct 5.  Standard python rounding get it right:

In [4]: round(123.6)
Out[4]: 124.0

In [5]: round(-123.6)
Out[5]: -124.0

Duane