- allows for simpler unpacking of a full list, or list range into any
sufficiently large integral type.
For example,
processorPolyPatch pp = ...;
UOPstream toNbr(pp.neighbProcNo(), pBufs);
toNbr << faceValues.unpack<char>(pp.range());
- The bitSet class replaces the old PackedBoolList class.
The redesign provides better block-wise access and reduced method
calls. This helps both in cases where the bitSet may be relatively
sparse, and in cases where advantage of contiguous operations can be
made. This makes it easier to work with a bitSet as top-level object.
In addition to the previously available count() method to determine
if a bitSet is being used, now have simpler queries:
- all() - true if all bits in the addressable range are empty
- any() - true if any bits are set at all.
- none() - true if no bits are set.
These are faster than count() and allow early termination.
The new test() method tests the value of a single bit position and
returns a bool without any ambiguity caused by the return type
(like the get() method), nor the const/non-const access (like
operator[] has). The name corresponds to what std::bitset uses.
The new find_first(), find_last(), find_next() methods provide a faster
means of searching for bits that are set.
This can be especially useful when using a bitSet to control an
conditional:
OLD (with macro):
forAll(selected, celli)
{
if (selected[celli])
{
sumVol += mesh_.cellVolumes()[celli];
}
}
NEW (with const_iterator):
for (const label celli : selected)
{
sumVol += mesh_.cellVolumes()[celli];
}
or manually
for
(
label celli = selected.find_first();
celli != -1;
celli = selected.find_next()
)
{
sumVol += mesh_.cellVolumes()[celli];
}
- When marking up contiguous parts of a bitset, an interval can be
represented more efficiently as a labelRange of start/size.
For example,
OLD:
if (isA<processorPolyPatch>(pp))
{
forAll(pp, i)
{
ignoreFaces.set(i);
}
}
NEW:
if (isA<processorPolyPatch>(pp))
{
ignoreFaces.set(pp.range());
}
- eliminate iterators from PackedList since they were unused, had
lower performance than direct access and added unneeded complexity.
- eliminate auto-vivify for the PackedList '[] operator.
The set() method provides any required auto-vivification and
removing this ability from the '[]' operator allows for a lower
when accessing the values. Replaced the previous cascade of iterators
with simpler reference class.
PackedBoolList:
- (temporarily) eliminate logic and addition operators since
these contained partially unclear semantics.
- the new test() method tests the value of a single bit position and
returns a bool without any ambiguity caused by the return type
(like the get() method), nor the const/non-const access (like
operator[] has). The name corresponds to what std::bitset uses.
- more consistent use of PackedBoolList test(), set(), unset() methods
for fewer operation and clearer code. Eg,
if (list.test(index)) ... | if (list[index]) ...
if (!list.test(index)) ... | if (list[index] == 0u) ...
list.set(index); | list[index] = 1u;
list.unset(index); | list[index] = 0u;
- deleted the operator=(const labelUList&) and replaced with a setMany()
method for more clarity about the intended operation and to avoid any
potential inadvertent behaviour.
- relocated ListAppendEqOp and ListUniqueEqOp to ListOps::appendEqOp
and ListOps::UniqueEqOp, respectively for better code isolation and
documentation of purpose.
- relocated setValues to ListOps::setValue() with many more
alternative selectors possible
- relocated createWithValues to ListOps::createWithValue
for better code isolation. The default initialization value is itself
now a default parameter, which allow for less typing.
Negative indices in the locations to set are now silently ignored,
which makes it possible to use an oldToNew mapping that includes
negative indices.
- additional ListOps::createWithValue taking a single position to set,
available both in copy assign and move assign versions.
Since a negative index is ignored, it is possible to combine with
the output of List::find() etc.
STYLE: changes for PackedList
- code simplication in the PackedList iterators, including dropping
the unused operator() on iterators, which is not available in plain
list versions either.
- improved sizing for PackedBoolList creation from a labelUList.
ENH: additional List constructors, for handling single element list.
- can assist in reducing constructor ambiguity, but can also helps
memory optimization when creating a single element list.
For example,
labelListList labels(one(), identity(mesh.nFaces()));
The compact ASCII format is a block of index/value tuples for the
non-zero entries:
{ (index1 value1) (index2 value2) (index3 value3) }
For PackedList<1>, and thus PackedBoolList, the compact ASCII format is
a block of indices for the non-zero entries:
{ index1 index2 index3 }
Thus either of the following could be used - for PackedList<2>:
- a list of all values:
16(0 3 0 2 0 0 3 1 0 0 0 0 0 0 0 1)
- a block of index/value tuples:
{(1 3) (3 2) (7 3) (8 1) (15 1)}
For PackedList<1> and PackedBoolList, either of the following could be
used:
- a list of all values, using any valid bool representation:
16(0 1 0 true 0 0 t 1 0 n n 0 0 0 0 yes)
- a block of the indices for non-zero entries:
{1 3 7 8 15}
ENH: adjust internal storage of PackedList to ensure that all unused
internal storage elements are guaranteed to always be bit-wise
zero. This makes the PackedBoolList implementation easier, and
also greatly eases much of the book-keeping.
Bits are now also zeroed on PackedList::clear()
Note: in PackedList, require packing at least 2 items otherwise it is
more efficient to use a normal list.
