classmethod galois.Array.repr(element_repr: 'int' | 'poly' | 'power' = 'int') → Generator[None, None, None]

Sets the element representation for all arrays from this FieldArray subclass.

The element representation can be set to either the integer, polynomial, or power representation. See Element Representation for a further discussion.

This function updates element_repr.

Danger

For the power representation, numpy.log() is computed on each element. So for large fields without lookup tables, displaying arrays in the power representation may take longer than expected.

Parameters:
element_repr: 'int' | 'poly' | 'power' = 'int'

The field element representation.

Returns:

A context manager for use in a with statement. If permanently setting the element representation, disregard the return value.

Examples

The default element representation is the integer representation.

In [1]: GF = galois.GF(3**2)

In [2]: x = GF.elements; x
Out[2]: GF([0, 1, 2, 3, 4, 5, 6, 7, 8], order=3^2)

Permanently set the element representation by calling repr().

In [3]: GF.repr("poly");

In [4]: x
Out[4]: 
GF([     0,      1,      2,      α,  α + 1,  α + 2,     2α, 2α + 1,
    2α + 2], order=3^2)

In [5]: GF.repr("power");

In [6]: x
Out[6]: GF([  0,   1, α^4,   α, α^2, α^7, α^5, α^3, α^6], order=3^2)

Temporarily modify the element representation by using repr() as a context manager.

In [7]: print(x)
[0 1 2 3 4 5 6 7 8]

In [8]: with GF.repr("poly"):
   ...:     print(x)
   ...: 
[     0      1      2      α  α + 1  α + 2     2α 2α + 1 2α + 2]

# Outside the context manager, the element representation reverts to its previous value
In [9]: print(x)
[0 1 2 3 4 5 6 7 8]

In [10]: print(x)
[0 1 2 3 4 5 6 7 8]

In [11]: with GF.repr("power"):
   ....:     print(x)
   ....: 
[  0   1 α^4   α α^2 α^7 α^5 α^3 α^6]

# Outside the context manager, the element representation reverts to its previous value
In [12]: print(x)
[0 1 2 3 4 5 6 7 8]