How to use addition, substraction, division and multiplicationΒΆ

Pretty sanely it is a leaf by leaf operation, and will work as long as element supports the operations.

>>> from vector_dict.VectorDict import convert_tree, VectorDict,Element,Path
>>> a = convert_tree(dict(a = dict(aint=1,afloat=2.0  , anarray=[1,2], astring="yo"), c= False))
>>> (a+a).tprint()
{
    a = {
        aint : 2,
        anarray : [1, 2, 1, 2],
        astring : 'yoyo',
        afloat : 4.0,
    },
    c = 0,
}
>>> (a*2).tprint()
{
    a : {
        aint : 2,
        anarray : [1, 2, 1, 2],
        astring : 'yoyo',
        afloat : 4.0,
    },
    c : 0,
}
>>> (a*a).tprint()
#Traceback (most recent call last):
#File "<input>", line 1, in <module>
#File "vector_dict/VectorDict.py", line 537, in __mul__
#  return self.__opfactory__(other, True)
#File "vector_dict/VectorDict.py", line 557, in __opfactory__
#  return getattr(a_copy, intern_operation)(other)
#File "vector_dict/VectorDict.py", line 852, in __internal_mul__
#  new_dict[k] = (self[k]).__internal_mul__( other[k] )
#File "vector_dict/VectorDict.py", line 854, in __internal_mul__
#  new_dict[k] = self[k] * other[k]
#TypeError: can't multiply sequence by non-int of type 'list'

It also works (in the rules of conservation) by creating new path/value in the new tree if it does not exists for addition. In multiplication if values are not present in both trees they are skipped.

>>> a = convert_tree(dict(a = dict(x=1, y=2.0, z=3), c= 1))
>>> b = convert_tree(dict(a = dict(x=-1.0, y=2.0, z=6), d= 1))
>>> (a+b).tprint()
{
    a : {
        y : 4.0,
        x : 0.0,
        z : 9,
    },
    c : 1,
    d : 1,
}
>>> (a*b).tprint()
{
    a : {
        y : 4.0,
        x : -1.0,
        z : 18,
    },
}
>>> (a-b).tprint()
{
    a : {
        y : 0.0,
        x : 2.0,
        z : -3,
    },
    c : 1,
    d : -1,
}
>>> (1.0*a/b).tprint()
{
    a : {
        y : 1.0,
        x : -1.0,
        z : 0.5,
    },
}

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