27 arithmetic operations for parameters

[damskii9992]

No description provided.

[rozyczko]

Apart from code review, a few things I found while testing

__radd__ vs. __add__ - should be consistent

    3+3+p -> "6+p"
    p+3+3 -> "p+3+3"

Nan/inf treatment. Are the p+np.inf bounds correct?

>>> p
<Parameter 'a': 1.0000, bounds=[-inf:inf]>
>>> p+np.inf
<Parameter 'a + inf': inf, bounds=[nan:inf]>
>>> p+np.nan
<Parameter 'a + nan': nan, bounds=[nan:nan]>

___div___ issue with the order (probably a scipp issue, or something wrong with __rdiv__ vs. __div__)

>>> a1
<Parameter 'a1': 2.0000 km, bounds=[-inf:inf]>
>>> a3
<Parameter 'a3': 2.0000 nm, bounds=[-inf:inf]>
>>> a1/a3
<Parameter 'a1 / a3': 1000000000000.0000, bounds=[-inf:inf]>
>>> a3/a1
scipp._scipp.core.UnitError: Conversion from `10e-13` to `2.18154854429043519e+244*s^(-13)*A^(-13)` is not valid.

[henrikjacobsenfys]

b2=Parameter("b2", 2.0)
In [20]: b3=b2+1
In [21]: b3
Out[21]: <Parameter 'b2 + 1': 3.0000, bounds=[-inf:inf]>
In [22]: b3*2
Out[22]: <Parameter 'b2 + 1 * 2': 6.0000, bounds=[-inf:inf]>

Should probably be
<Parameter '(b2 + 1) * 2': 6.0000, bounds=[-inf:inf]>