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BiDict

BiDict

BiDict (Bidirectional Dictionary) provides a one-to-one mapping between keys and values.

Supports both forward and reverse lookup.

Source code in pyrad2/bidict.py 
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class BiDict:
    """BiDict (Bidirectional Dictionary) provides a one-to-one mapping
    between keys and values.

    Supports both forward and reverse lookup.
    """

    def __init__(self) -> None:
        """Initialize empty forward and reverse dictionaries."""
        self.forward: Dict[Hashable, Any] = {}
        self.backward: Dict[Hashable, Any] = {}

    def Add(self, one: Hashable, two: Hashable) -> None:
        """Add a bidirectional mapping between 'one' and 'two'."""
        self.forward[one] = two
        self.backward[two] = one

    def __len__(self) -> int:
        """Return the number of entries in the dictionary."""
        return len(self.forward)

    def __getitem__(self, key: Hashable) -> Any:
        """Retrieve the value associated with the given key."""
        return self.GetForward(key)

    def __delitem__(self, key: Hashable) -> None:
        """Remove key and its associated value from the dictionary."""
        if key in self.forward:
            del self.backward[self.forward[key]]
            del self.forward[key]
        else:
            del self.forward[self.backward[key]]
            del self.backward[key]

    def GetForward(self, key: Hashable) -> Any:
        """Return the value associated with 'key' from the forward mapping."""
        return self.forward[key]

    def HasForward(self, key: Hashable) -> bool:
        """Check if 'key' exists in the forward mapping."""
        return key in self.forward

    def GetBackward(self, key: Hashable) -> Any:
        """Return the key associated with 'value' from the reverse mapping."""
        return self.backward[key]

    def HasBackward(self, key: Hashable) -> bool:
        """Check if 'value' exists in the reverse mapping."""
        return key in self.backward

__init__()

Initialize empty forward and reverse dictionaries.

Source code in pyrad2/bidict.py 
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def __init__(self) -> None:
    """Initialize empty forward and reverse dictionaries."""
    self.forward: Dict[Hashable, Any] = {}
    self.backward: Dict[Hashable, Any] = {}

Add(one, two)

Add a bidirectional mapping between 'one' and 'two'.

Source code in pyrad2/bidict.py 
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def Add(self, one: Hashable, two: Hashable) -> None:
    """Add a bidirectional mapping between 'one' and 'two'."""
    self.forward[one] = two
    self.backward[two] = one

__len__()

Return the number of entries in the dictionary.

Source code in pyrad2/bidict.py 
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def __len__(self) -> int:
    """Return the number of entries in the dictionary."""
    return len(self.forward)

__getitem__(key)

Retrieve the value associated with the given key.

Source code in pyrad2/bidict.py 
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def __getitem__(self, key: Hashable) -> Any:
    """Retrieve the value associated with the given key."""
    return self.GetForward(key)

__delitem__(key)

Remove key and its associated value from the dictionary.

Source code in pyrad2/bidict.py 
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def __delitem__(self, key: Hashable) -> None:
    """Remove key and its associated value from the dictionary."""
    if key in self.forward:
        del self.backward[self.forward[key]]
        del self.forward[key]
    else:
        del self.forward[self.backward[key]]
        del self.backward[key]

GetForward(key)

Return the value associated with 'key' from the forward mapping.

Source code in pyrad2/bidict.py 
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def GetForward(self, key: Hashable) -> Any:
    """Return the value associated with 'key' from the forward mapping."""
    return self.forward[key]

HasForward(key)

Check if 'key' exists in the forward mapping.

Source code in pyrad2/bidict.py 
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def HasForward(self, key: Hashable) -> bool:
    """Check if 'key' exists in the forward mapping."""
    return key in self.forward

GetBackward(key)

Return the key associated with 'value' from the reverse mapping.

Source code in pyrad2/bidict.py 
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def GetBackward(self, key: Hashable) -> Any:
    """Return the key associated with 'value' from the reverse mapping."""
    return self.backward[key]

HasBackward(key)

Check if 'value' exists in the reverse mapping.

Source code in pyrad2/bidict.py 
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def HasBackward(self, key: Hashable) -> bool:
    """Check if 'value' exists in the reverse mapping."""
    return key in self.backward