Struct arrow2::bitmap::MutableBitmap
source · [−]pub struct MutableBitmap { /* private fields */ }
Expand description
A container of booleans. MutableBitmap
is semantically equivalent
to Vec<bool>
.
The two main differences against Vec<bool>
is that each element stored as a single bit,
thereby:
- it uses 8x less memory
- it cannot be represented as
&[bool]
(i.e. no pointer arithmetics).
A MutableBitmap
can be converted to a Bitmap
at O(1)
.
Examples
use arrow2::bitmap::MutableBitmap;
let bitmap = MutableBitmap::from([true, false, true]);
assert_eq!(bitmap.iter().collect::<Vec<_>>(), vec![true, false, true]);
// creation directly from bytes
let mut bitmap = MutableBitmap::try_new(vec![0b00001101], 5).unwrap();
// note: the first bit is the left-most of the first byte
assert_eq!(bitmap.iter().collect::<Vec<_>>(), vec![true, false, true, true, false]);
// we can also get the slice:
assert_eq!(bitmap.as_slice(), [0b00001101u8].as_ref());
// debug helps :)
assert_eq!(format!("{:?}", bitmap), "[0b___01101]".to_string());
// It supports mutation in place
bitmap.set(0, false);
assert_eq!(format!("{:?}", bitmap), "[0b___01100]".to_string());
// and `O(1)` random access
assert_eq!(bitmap.get(0), false);
Implementation
This container is internally a Vec<u8>
.
Implementations
sourceimpl MutableBitmap
impl MutableBitmap
sourcepub fn new() -> Self
pub fn new() -> Self
Initializes an empty MutableBitmap
.
sourcepub fn try_new(bytes: Vec<u8>, length: usize) -> Result<Self, Error>
pub fn try_new(bytes: Vec<u8>, length: usize) -> Result<Self, Error>
Initializes a new MutableBitmap
from a Vec<u8>
and a length.
Errors
This function errors iff length > bytes.len() * 8
sourcepub fn from_vec(buffer: Vec<u8>, length: usize) -> Self
pub fn from_vec(buffer: Vec<u8>, length: usize) -> Self
Initializes a MutableBitmap
from a Vec<u8>
and a length.
This function is O(1)
.
Panic
Panics iff the length is larger than the length of the buffer times 8.
sourcepub fn with_capacity(capacity: usize) -> Self
pub fn with_capacity(capacity: usize) -> Self
Initializes a pre-allocated MutableBitmap
with capacity for capacity
bits.
sourcepub fn push(&mut self, value: bool)
pub fn push(&mut self, value: bool)
Pushes a new bit to the MutableBitmap
, re-sizing it if necessary.
sourcepub fn pop(&mut self) -> Option<bool>
pub fn pop(&mut self) -> Option<bool>
Pop the last bit from the MutableBitmap
.
Note if the MutableBitmap
is empty, this method will return None.
sourcepub fn iter(&self) -> BitmapIter<'_>ⓘNotable traits for BitmapIter<'a>impl<'a> Iterator for BitmapIter<'a> type Item = bool;
pub fn iter(&self) -> BitmapIter<'_>ⓘNotable traits for BitmapIter<'a>impl<'a> Iterator for BitmapIter<'a> type Item = bool;
constructs a new iterator over the bits of MutableBitmap
.
sourcepub fn clear(&mut self)
pub fn clear(&mut self)
Empties the MutableBitmap
.
sourcepub fn extend_constant(&mut self, additional: usize, value: bool)
pub fn extend_constant(&mut self, additional: usize, value: bool)
Extends MutableBitmap
by additional
values of constant value
.
Implementation
This function is an order of magnitude faster than pushing element by element.
sourcepub fn from_len_zeroed(length: usize) -> Self
pub fn from_len_zeroed(length: usize) -> Self
Initializes a zeroed MutableBitmap
.
sourcepub fn from_len_set(length: usize) -> Self
pub fn from_len_set(length: usize) -> Self
Initializes a MutableBitmap
with all values set to valid/ true.
sourcepub fn reserve(&mut self, additional: usize)
pub fn reserve(&mut self, additional: usize)
Reserves additional
bits in the MutableBitmap
, potentially re-allocating its buffer.
sourcepub fn capacity(&self) -> usize
pub fn capacity(&self) -> usize
Returns the capacity of MutableBitmap
in number of bits.
sourcepub unsafe fn push_unchecked(&mut self, value: bool)
pub unsafe fn push_unchecked(&mut self, value: bool)
Pushes a new bit to the MutableBitmap
Safety
The caller must ensure that the MutableBitmap
has sufficient capacity.
sourcepub fn unset_bits(&self) -> usize
pub fn unset_bits(&self) -> usize
Returns the number of unset bits on this MutableBitmap
.
Guaranted to be <= self.len()
.
Implementation
This function is O(N)
sourcepub fn null_count(&self) -> usize
👎 Deprecated since 0.13.0: use unset_bits
instead
pub fn null_count(&self) -> usize
use unset_bits
instead
Returns the number of unset bits on this MutableBitmap
.
sourcepub fn len(&self) -> usize
pub fn len(&self) -> usize
Returns the length of the MutableBitmap
.
sourcepub fn is_empty(&self) -> bool
pub fn is_empty(&self) -> bool
Returns whether MutableBitmap
is empty.
sourcepub unsafe fn set_unchecked(&mut self, index: usize, value: bool)
pub unsafe fn set_unchecked(&mut self, index: usize, value: bool)
sourcepub fn shrink_to_fit(&mut self)
pub fn shrink_to_fit(&mut self)
Shrinks the capacity of the MutableBitmap
to fit its current length.
sourceimpl MutableBitmap
impl MutableBitmap
sourcepub fn extend_from_trusted_len_iter<I: TrustedLen<Item = bool>>(
&mut self,
iterator: I
)
pub fn extend_from_trusted_len_iter<I: TrustedLen<Item = bool>>(
&mut self,
iterator: I
)
Extends self
from a TrustedLen
iterator.
sourcepub unsafe fn extend_from_trusted_len_iter_unchecked<I: Iterator<Item = bool>>(
&mut self,
iterator: I
)
pub unsafe fn extend_from_trusted_len_iter_unchecked<I: Iterator<Item = bool>>(
&mut self,
iterator: I
)
Extends self
from an iterator of trusted len.
Safety
The caller must guarantee that the iterator has a trusted len.
sourcepub unsafe fn from_trusted_len_iter_unchecked<I>(iterator: I) -> Self where
I: Iterator<Item = bool>,
pub unsafe fn from_trusted_len_iter_unchecked<I>(iterator: I) -> Self where
I: Iterator<Item = bool>,
Creates a new MutableBitmap
from an iterator of booleans.
Safety
The iterator must report an accurate length.
sourcepub fn from_trusted_len_iter<I>(iterator: I) -> Self where
I: TrustedLen<Item = bool>,
pub fn from_trusted_len_iter<I>(iterator: I) -> Self where
I: TrustedLen<Item = bool>,
Creates a new MutableBitmap
from an iterator of booleans.
sourcepub fn try_from_trusted_len_iter<E, I>(iterator: I) -> Result<Self, E> where
I: TrustedLen<Item = Result<bool, E>>,
pub fn try_from_trusted_len_iter<E, I>(iterator: I) -> Result<Self, E> where
I: TrustedLen<Item = Result<bool, E>>,
Creates a new MutableBitmap
from an iterator of booleans.
sourcepub unsafe fn try_from_trusted_len_iter_unchecked<E, I>(
iterator: I
) -> Result<Self, E> where
I: Iterator<Item = Result<bool, E>>,
pub unsafe fn try_from_trusted_len_iter_unchecked<E, I>(
iterator: I
) -> Result<Self, E> where
I: Iterator<Item = Result<bool, E>>,
Creates a new MutableBitmap
from an falible iterator of booleans.
Safety
The caller must guarantee that the iterator is TrustedLen
.
sourcepub fn extend_from_slice(&mut self, slice: &[u8], offset: usize, length: usize)
pub fn extend_from_slice(&mut self, slice: &[u8], offset: usize, length: usize)
Extends the MutableBitmap
from a slice of bytes with optional offset.
This is the fastest way to extend a MutableBitmap
.
Implementation
When both MutableBitmap
’s length and offset
are both multiples of 8,
this function performs a memcopy. Else, it first aligns bit by bit and then performs a memcopy.
sourcepub fn extend_from_bitmap(&mut self, bitmap: &Bitmap)
pub fn extend_from_bitmap(&mut self, bitmap: &Bitmap)
Extends the MutableBitmap
from a Bitmap
.
Trait Implementations
sourceimpl<'a> BitAnd<&'a Bitmap> for MutableBitmap
impl<'a> BitAnd<&'a Bitmap> for MutableBitmap
sourceimpl<'a> BitAndAssign<&'a Bitmap> for &mut MutableBitmap
impl<'a> BitAndAssign<&'a Bitmap> for &mut MutableBitmap
sourcefn bitand_assign(&mut self, rhs: &'a Bitmap)
fn bitand_assign(&mut self, rhs: &'a Bitmap)
Performs the &=
operation. Read more
sourceimpl<'a> BitOr<&'a Bitmap> for MutableBitmap
impl<'a> BitOr<&'a Bitmap> for MutableBitmap
sourceimpl<'a> BitOrAssign<&'a Bitmap> for &mut MutableBitmap
impl<'a> BitOrAssign<&'a Bitmap> for &mut MutableBitmap
sourcefn bitor_assign(&mut self, rhs: &'a Bitmap)
fn bitor_assign(&mut self, rhs: &'a Bitmap)
Performs the |=
operation. Read more
sourceimpl<'a> BitXor<&'a Bitmap> for MutableBitmap
impl<'a> BitXor<&'a Bitmap> for MutableBitmap
sourceimpl<'a> BitXorAssign<&'a Bitmap> for &mut MutableBitmap
impl<'a> BitXorAssign<&'a Bitmap> for &mut MutableBitmap
sourcefn bitxor_assign(&mut self, rhs: &'a Bitmap)
fn bitxor_assign(&mut self, rhs: &'a Bitmap)
Performs the ^=
operation. Read more
sourceimpl Clone for MutableBitmap
impl Clone for MutableBitmap
sourcefn clone(&self) -> MutableBitmap
fn clone(&self) -> MutableBitmap
Returns a copy of the value. Read more
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from source
. Read more
sourceimpl Debug for MutableBitmap
impl Debug for MutableBitmap
sourceimpl Default for MutableBitmap
impl Default for MutableBitmap
sourceimpl From<MutableBitmap> for Bitmap
impl From<MutableBitmap> for Bitmap
sourcefn from(buffer: MutableBitmap) -> Self
fn from(buffer: MutableBitmap) -> Self
Converts to this type from the input type.
sourceimpl From<MutableBitmap> for Option<Bitmap>
impl From<MutableBitmap> for Option<Bitmap>
sourcefn from(buffer: MutableBitmap) -> Self
fn from(buffer: MutableBitmap) -> Self
Converts to this type from the input type.
sourceimpl<P: AsRef<[bool]>> From<P> for MutableBitmap
impl<P: AsRef<[bool]>> From<P> for MutableBitmap
sourceimpl FromIterator<bool> for MutableBitmap
impl FromIterator<bool> for MutableBitmap
sourcefn from_iter<I>(iter: I) -> Self where
I: IntoIterator<Item = bool>,
fn from_iter<I>(iter: I) -> Self where
I: IntoIterator<Item = bool>,
Creates a value from an iterator. Read more
sourceimpl<'a> IntoIterator for &'a MutableBitmap
impl<'a> IntoIterator for &'a MutableBitmap
sourceimpl Not for MutableBitmap
impl Not for MutableBitmap
type Output = MutableBitmap
type Output = MutableBitmap
The resulting type after applying the !
operator.
sourceimpl PartialEq<MutableBitmap> for MutableBitmap
impl PartialEq<MutableBitmap> for MutableBitmap
Auto Trait Implementations
impl RefUnwindSafe for MutableBitmap
impl Send for MutableBitmap
impl Sync for MutableBitmap
impl Unpin for MutableBitmap
impl UnwindSafe for MutableBitmap
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more