Struct arrow::array::DecimalArray

pub struct DecimalArray { /* private fields */ }

DecimalArray stores fixed width decimal numbers, with a fixed precision and scale.

Examples

   use arrow::array::{Array, DecimalArray};
   use arrow::datatypes::DataType;

   // Create a DecimalArray with the default precision and scale
   let decimal_array: DecimalArray = vec![
      Some(8_887_000_000),
      None,
      Some(-8_887_000_000),
    ]
    .into_iter().collect();

   // set precision and scale so values are interpreted
   // as `8887.000000`, `Null`, and `-8887.000000`
   let decimal_array = decimal_array
    .with_precision_and_scale(23, 6)
    .unwrap();

   assert_eq!(&DataType::Decimal(23, 6), decimal_array.data_type());
   assert_eq!(8_887_000_000, decimal_array.value(0));
   assert_eq!("8887.000000", decimal_array.value_as_string(0));
   assert_eq!(3, decimal_array.len());
   assert_eq!(1, decimal_array.null_count());
   assert_eq!(32, decimal_array.value_offset(2));
   assert_eq!(16, decimal_array.value_length());
   assert_eq!(23, decimal_array.precision());
   assert_eq!(6, decimal_array.scale());

Implementations

impl DecimalArray

pub fn value(&self, i: usize) -> i128

Returns the element at index i as i128.

pub fn value_offset(&self, i: usize) -> i32

Returns the offset for the element at index i.

Note this doesn’t do any bound checking, for performance reason.

pub fn value_length(&self) -> i32

Returns the length for an element.

All elements have the same length as the array is a fixed size.

pub fn value_data(&self) -> Buffer

Returns a clone of the value data buffer

pub fn value_as_string(&self, row: usize) -> String

pub fn from_fixed_size_list_array(
    v: FixedSizeListArray,
    precision: usize,
    scale: usize
) -> Self

pub fn from_iter_values<I: IntoIterator<Item = i128>>(iter: I) -> Self

Creates a DecimalArray with default precision and scale, based on an iterator of i128 values without nulls

pub fn precision(&self) -> usize

Return the precision (total digits) that can be stored by this array

pub fn scale(&self) -> usize

Return the scale (digits after the decimal) that can be stored by this array

pub fn with_precision_and_scale(
    self,
    precision: usize,
    scale: usize
) -> Result<Self>

Returns a DecimalArray with the same data as self, with the specified precision.

Returns an Error if:

1. precision is larger than DECIMAL_MAX_PRECISION
2. scale is larger than DECIMAL_MAX_SCALE;
3. scale is > precision

pub fn default_type() -> DataType

The default precision and scale used when not specified.

impl<'a> DecimalArray

pub fn iter(&'a self) -> DecimalIter<'a>

constructs a new iterator

Trait Implementations

impl Array for DecimalArray

fn as_any(&self) -> &dyn Any

Returns the array as Any so that it can be downcasted to a specific implementation.

fn data(&self) -> &ArrayData

Returns a reference to the underlying data of this array.

fn data_ref(&self) -> &ArrayData

Returns a reference-counted pointer to the underlying data of this array.

fn data_type(&self) -> &DataType

Returns a reference to the DataType of this array.

fn slice(&self, offset: usize, length: usize) -> ArrayRef

Returns a zero-copy slice of this array with the indicated offset and length.

fn len(&self) -> usize

Returns the length (i.e., number of elements) of this array.

fn is_empty(&self) -> bool

Returns whether this array is empty.

fn offset(&self) -> usize

Returns the offset into the underlying data used by this array(-slice). Note that the underlying data can be shared by many arrays. This defaults to 0.

fn is_null(&self, index: usize) -> bool

Returns whether the element at index is null. When using this function on a slice, the index is relative to the slice.

fn is_valid(&self, index: usize) -> bool

Returns whether the element at index is not null. When using this function on a slice, the index is relative to the slice.

fn null_count(&self) -> usize

Returns the total number of null values in this array.

fn get_buffer_memory_size(&self) -> usize

Returns the total number of bytes of memory pointed to by this array. The buffers store bytes in the Arrow memory format, and include the data as well as the validity map.

fn get_array_memory_size(&self) -> usize

Returns the total number of bytes of memory occupied physically by this array. This value will always be greater than returned by get_buffer_memory_size() and includes the overhead of the data structures that contain the pointers to the various buffers.

fn to_raw(&self) -> Result<(*const FFI_ArrowArray, *const FFI_ArrowSchema)>

returns two pointers that represent this array in the C Data Interface (FFI)

impl Debug for DecimalArray

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<ArrayData> for DecimalArray

fn from(data: ArrayData) -> Self

Converts to this type from the input type.

impl From<DecimalArray> for ArrayData

fn from(array: DecimalArray) -> Self

Converts to this type from the input type.

impl<Ptr: Borrow<Option<i128>>> FromIterator<Ptr> for DecimalArray

fn from_iter<I: IntoIterator<Item = Ptr>>(iter: I) -> Self

Creates a value from an iterator.

impl<'a> IntoIterator for &'a DecimalArray

type Item = Option<i128>

The type of the elements being iterated over.

type IntoIter = DecimalIter<'a>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl JsonEqual for DecimalArray

fn equals_json(&self, json: &[&Value]) -> bool

Checks whether arrow array equals to json array.

fn equals_json_values(&self, json: &[Value]) -> bool

Checks whether arrow array equals to json array.

impl PartialEq<DecimalArray> for DecimalArray

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialEq<DecimalArray> for Value

fn eq(&self, arrow: &DecimalArray) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialEq<Value> for DecimalArray

fn eq(&self, json: &Value) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.