EwahCompressedBitArray Methods |
The EwahCompressedBitArray type exposes the following members.
Methods| Name | Description | |
|---|---|---|
 | Add(Int64) |
Adding words directly to the bitmap (for expert use).
This is normally how you add data to the array. So you add bits in streams
of 8*8 bits.
|
| Add(Int64, Int32) |
Adding words directly to the bitmap (for expert use).
|
| AddStreamOfEmptyWords |
For experts: You want to add many
zeroes or ones? This is the method you use.
|
| And |
Returns a new compressed bitmap containing the bitwise AND values of the
current bitmap with some other bitmap.
The running time is proportional to the sum of the compressed sizes (as
reported by SizeInBytes).
|
| AndNot |
Returns a new compressed bitmap containing the bitwise AND NOT values of
the current bitmap with some other bitmap.
The running time is proportional to the sum of the compressed sizes (as
reported by SizeInBytes).
|
 | bitCount |
Counts the number of set (1) bits.
|
| BitmapOf | |
| Clone | (Overrides OptimizedPersistableClone.) |
| Equals |
Check to see whether the two compressed bitmaps contain the same data
(effectively check whether the cardinality of a XOR is == 0.
(Overrides OptimizedPersistableEquals(Object).) |
| GetCardinality |
reports the number of bits set to true. Running time is proportional to
compressed size (as reported by SizeInBytes).
|
| GetEnumerator |
Iterator over the set bits (this is what most people will want to use to
browse the content). The location of the set bits is returned, in
increasing order.
|
| GetHashCode |
Returns a customized hash code (based on Karp-Rabin).
Naturally, if the bitmaps are equal, they will hash to the same value.
(Overrides OptimizedPersistableGetHashCode.) |
| GetObjectData | |
| GetPositions |
get the locations of the true values as one vector. (may use more memory
than GetEnumerator() |
| Intersects |
Return true if the two EwahCompressedBitArray have both at least one
true bit in the same Position. Equivalently, you could call "And"
and check whether there is a set bit, but intersects will run faster
if you don't need the result of the "and" operation.
|
| Not |
Negate (bitwise) the current bitmap. To get a negated copy, do
((EwahCompressedBitArray) mybitmap.Clone()).not();
The running time is proportional to the compressed size (as reported by
SizeInBytes).
|
| Or |
Returns a new compressed bitmap containing the bitwise OR values of the
current bitmap with some other bitmap.
The running time is proportional to the sum of the compressed sizes (as
reported by SizeInBytes).
|
| Set |
set the bit at Position i to true, the bits must be set in increasing
order. For example, Set(15) and then Set(7) will fail. You must do Set(7)
and then Set(15).
|
| SetSizeInBits |
Change the reported size in bits of the *uncompressed* bitmap represented
by this compressed bitmap. It is not possible to reduce the SizeInBits, but
it can be extended. The new bits are set to false or true depending on the
value of defaultvalue.
|
| Shrink |
Sets the internal buffer to the minimum possible size required to contain
the current bitarray.
This method is useful when dealing with static bitmasks, if it is called
after the final bit has been set, some memory can be free-ed.
Please note, the next bit set after a call to shrink will cause the memory
usage of the bit-array to double.
|
| ToDebugString |
A more detailed string describing the bitmap (useful for debugging).
|
| ToString |
A string describing the bitmap
(Overrides OptimizedPersistableToString.) |
| Xor |
Returns a new compressed bitmap containing the bitwise XOR values of the
current bitmap with some other bitmap.
The running time is proportional to the sum of the compressed sizes (as
reported by SizeInBytes).
|
Extension Methods| Name | Description | |
|---|---|---|
 | ToStringDetails(SessionBase, Boolean) | Overloaded.
Object details as a string
(Defined by Utilities.) |
| ToStringDetails(Schema, TypeVersion, Boolean) | Overloaded.
Currently only used by Database Manager
(Defined by Utilities.) |
See Also