Added support for scalar comparison of dictionary.

Cargo.toml

@@ -158,7 +158,7 @@ compute_bitwise = []
 compute_boolean = []
 compute_boolean_kleene = []
 compute_cast = ["lexical-core", "compute_take"]
-compute_comparison = []
+compute_comparison = ["compute_take"]
 compute_concatenate = []
 compute_contains = []
 compute_filter = []

src/compute/comparison/mod.rs

@@ -56,6 +56,7 @@ pub mod utf8;
 mod simd;
 pub use simd::{Simd8, Simd8Lanes, Simd8PartialEq, Simd8PartialOrd};
 
+use super::take::take_boolean;
 pub(crate) use primitive::{
     compare_values_op as primitive_compare_values_op,
     compare_values_op_scalar as primitive_compare_values_op_scalar,
@@ -166,6 +167,11 @@ pub fn eq(lhs: &dyn Array, rhs: &dyn Array) -> BooleanArray {
     compare!(lhs, rhs, eq, match_eq)
 }
 
+/// Returns whether a [`DataType`] is comparable is supported by [`eq`].
+pub fn can_eq(data_type: &DataType) -> bool {
+    can_partial_eq(data_type)
+}
+
 /// `!=` between two [`Array`]s.
 /// Use [`can_neq`] to check whether the operation is valid
 /// # Panic
@@ -177,6 +183,11 @@ pub fn neq(lhs: &dyn Array, rhs: &dyn Array) -> BooleanArray {
     compare!(lhs, rhs, neq, match_eq)
 }
 
+/// Returns whether a [`DataType`] is comparable is supported by [`neq`].
+pub fn can_neq(data_type: &DataType) -> bool {
+    can_partial_eq(data_type)
+}
+
 /// `<` between two [`Array`]s.
 /// Use [`can_lt`] to check whether the operation is valid
 /// # Panic
@@ -188,6 +199,11 @@ pub fn lt(lhs: &dyn Array, rhs: &dyn Array) -> BooleanArray {
     compare!(lhs, rhs, lt, match_eq_ord)
 }
 
+/// Returns whether a [`DataType`] is comparable is supported by [`lt`].
+pub fn can_lt(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord(data_type)
+}
+
 /// `<=` between two [`Array`]s.
 /// Use [`can_lt_eq`] to check whether the operation is valid
 /// # Panic
@@ -199,6 +215,11 @@ pub fn lt_eq(lhs: &dyn Array, rhs: &dyn Array) -> BooleanArray {
     compare!(lhs, rhs, lt_eq, match_eq_ord)
 }
 
+/// Returns whether a [`DataType`] is comparable is supported by [`lt`].
+pub fn can_lt_eq(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord(data_type)
+}
+
 /// `>` between two [`Array`]s.
 /// Use [`can_gt`] to check whether the operation is valid
 /// # Panic
@@ -210,6 +231,11 @@ pub fn gt(lhs: &dyn Array, rhs: &dyn Array) -> BooleanArray {
     compare!(lhs, rhs, gt, match_eq_ord)
 }
 
+/// Returns whether a [`DataType`] is comparable is supported by [`gt`].
+pub fn can_gt(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord(data_type)
+}
+
 /// `>=` between two [`Array`]s.
 /// Use [`can_gt_eq`] to check whether the operation is valid
 /// # Panic
@@ -221,6 +247,11 @@ pub fn gt_eq(lhs: &dyn Array, rhs: &dyn Array) -> BooleanArray {
     compare!(lhs, rhs, gt_eq, match_eq_ord)
 }
 
+/// Returns whether a [`DataType`] is comparable is supported by [`gt_eq`].
+pub fn can_gt_eq(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord(data_type)
+}
+
 macro_rules! compare_scalar {
     ($lhs:expr, $rhs:expr, $op:tt, $p:tt) => {{
         let lhs = $lhs;
@@ -266,13 +297,21 @@ macro_rules! compare_scalar {
                 let rhs = rhs.as_any().downcast_ref::<BinaryScalar<i64>>().unwrap();
                 binary::$op::<i64>(lhs, rhs.value().unwrap())
             }
+            Dictionary(key_type) => {
+                match_integer_type!(key_type, |$T| {
+                    let lhs = lhs.as_any().downcast_ref::<DictionaryArray<$T>>().unwrap();
+                    let values = $op(lhs.values().as_ref(), rhs);
+
+                    take_boolean(&values, lhs.keys())
+                })
+            }
             _ => todo!("Comparisons of {:?} are not yet supported", lhs.data_type()),
         }
     }};
 }
 
 /// `==` between an [`Array`] and a [`Scalar`].
-/// Use [`can_eq`] to check whether the operation is valid
+/// Use [`can_eq_scalar`] to check whether the operation is valid
 /// # Panic
 /// Panics iff either:
 /// * they do not have have the same logical type
@@ -281,8 +320,13 @@ pub fn eq_scalar(lhs: &dyn Array, rhs: &dyn Scalar) -> BooleanArray {
     compare_scalar!(lhs, rhs, eq_scalar, match_eq)
 }
 
+/// Returns whether a [`DataType`] is supported by [`eq_scalar`].
+pub fn can_eq_scalar(data_type: &DataType) -> bool {
+    can_partial_eq_scalar(data_type)
+}
+
 /// `!=` between an [`Array`] and a [`Scalar`].
-/// Use [`can_neq`] to check whether the operation is valid
+/// Use [`can_neq_scalar`] to check whether the operation is valid
 /// # Panic
 /// Panics iff either:
 /// * they do not have have the same logical type
@@ -291,8 +335,13 @@ pub fn neq_scalar(lhs: &dyn Array, rhs: &dyn Scalar) -> BooleanArray {
     compare_scalar!(lhs, rhs, neq_scalar, match_eq)
 }
 
+/// Returns whether a [`DataType`] is supported by [`neq_scalar`].
+pub fn can_neq_scalar(data_type: &DataType) -> bool {
+    can_partial_eq_scalar(data_type)
+}
+
 /// `<` between an [`Array`] and a [`Scalar`].
-/// Use [`can_lt`] to check whether the operation is valid
+/// Use [`can_lt_scalar`] to check whether the operation is valid
 /// # Panic
 /// Panics iff either:
 /// * they do not have have the same logical type
@@ -301,8 +350,13 @@ pub fn lt_scalar(lhs: &dyn Array, rhs: &dyn Scalar) -> BooleanArray {
     compare_scalar!(lhs, rhs, lt_scalar, match_eq_ord)
 }
 
+/// Returns whether a [`DataType`] is supported by [`lt_scalar`].
+pub fn can_lt_scalar(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord_scalar(data_type)
+}
+
 /// `<=` between an [`Array`] and a [`Scalar`].
-/// Use [`can_lt_eq`] to check whether the operation is valid
+/// Use [`can_lt_eq_scalar`] to check whether the operation is valid
 /// # Panic
 /// Panics iff either:
 /// * they do not have have the same logical type
@@ -311,8 +365,13 @@ pub fn lt_eq_scalar(lhs: &dyn Array, rhs: &dyn Scalar) -> BooleanArray {
     compare_scalar!(lhs, rhs, lt_eq_scalar, match_eq_ord)
 }
 
+/// Returns whether a [`DataType`] is supported by [`lt_eq_scalar`].
+pub fn can_lt_eq_scalar(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord_scalar(data_type)
+}
+
 /// `>` between an [`Array`] and a [`Scalar`].
-/// Use [`can_gt`] to check whether the operation is valid
+/// Use [`can_gt_scalar`] to check whether the operation is valid
 /// # Panic
 /// Panics iff either:
 /// * they do not have have the same logical type
@@ -321,8 +380,13 @@ pub fn gt_scalar(lhs: &dyn Array, rhs: &dyn Scalar) -> BooleanArray {
     compare_scalar!(lhs, rhs, gt_scalar, match_eq_ord)
 }
 
+/// Returns whether a [`DataType`] is supported by [`gt_scalar`].
+pub fn can_gt_scalar(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord_scalar(data_type)
+}
+
 /// `>=` between an [`Array`] and a [`Scalar`].
-/// Use [`can_gt_eq`] to check whether the operation is valid
+/// Use [`can_gt_eq_scalar`] to check whether the operation is valid
 /// # Panic
 /// Panics iff either:
 /// * they do not have have the same logical type
@@ -331,33 +395,16 @@ pub fn gt_eq_scalar(lhs: &dyn Array, rhs: &dyn Scalar) -> BooleanArray {
     compare_scalar!(lhs, rhs, gt_eq_scalar, match_eq_ord)
 }
 
-/// Returns whether a [`DataType`] is comparable (either array or scalar).
-pub fn can_eq(data_type: &DataType) -> bool {
-    can_partial_eq(data_type)
-}
-
-/// Returns whether a [`DataType`] is comparable (either array or scalar).
-pub fn can_neq(data_type: &DataType) -> bool {
-    can_partial_eq(data_type)
+/// Returns whether a [`DataType`] is supported by [`gt_eq_scalar`].
+pub fn can_gt_eq_scalar(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord_scalar(data_type)
 }
 
-/// Returns whether a [`DataType`] is comparable (either array or scalar).
-pub fn can_lt(data_type: &DataType) -> bool {
-    can_partial_eq_and_ord(data_type)
-}
-
-/// Returns whether a [`DataType`] is comparable (either array or scalar).
-pub fn can_lt_eq(data_type: &DataType) -> bool {
-    can_partial_eq_and_ord(data_type)
-}
-
-/// Returns whether a [`DataType`] is comparable (either array or scalar).
-pub fn can_gt(data_type: &DataType) -> bool {
-    can_partial_eq_and_ord(data_type)
-}
-
-/// Returns whether a [`DataType`] is comparable (either array or scalar).
-pub fn can_gt_eq(data_type: &DataType) -> bool {
+// The list of operations currently supported.
+fn can_partial_eq_and_ord_scalar(data_type: &DataType) -> bool {
+    if let DataType::Dictionary(_, values, _) = data_type.to_logical_type() {
+        return can_partial_eq_and_ord_scalar(values.as_ref());
+    }
     can_partial_eq_and_ord(data_type)
 }
 
@@ -400,3 +447,13 @@ fn can_partial_eq(data_type: &DataType) -> bool {
                 | DataType::Interval(IntervalUnit::MonthDayNano)
         )
 }
+
+// The list of operations currently supported.
+fn can_partial_eq_scalar(data_type: &DataType) -> bool {
+    can_partial_eq_and_ord_scalar(data_type)
+        || matches!(
+            data_type.to_logical_type(),
+            DataType::Interval(IntervalUnit::DayTime)
+                | DataType::Interval(IntervalUnit::MonthDayNano)
+        )
+}

src/compute/take/mod.rs

@@ -33,6 +33,8 @@ mod primitive;
 mod structure;
 mod utf8;
 
+pub(crate) use boolean::take as take_boolean;
+
 /// Returns a new [`Array`] with only indices at `indices`. Null indices are taken as nulls.
 /// The returned array has a length equal to `indices.len()`.
 pub fn take<O: Index>(values: &dyn Array, indices: &PrimitiveArray<O>) -> Result<Box<dyn Array>> {

src/types/index.rs

@@ -11,10 +11,10 @@ pub trait Index:
     + std::ops::AddAssign
     + std::ops::Sub<Output = Self>
     + num_traits::One
-    + PartialOrd
     + num_traits::Num
-    + Ord
     + num_traits::CheckedAdd
+    + PartialOrd
+    + Ord
 {
     /// Convert itself to [`usize`].
     fn to_usize(&self) -> usize;
@@ -32,53 +32,30 @@ pub trait Index:
     }
 }
 
-impl Index for i32 {
-    #[inline]
-    fn to_usize(&self) -> usize {
-        *self as usize
-    }
-
-    #[inline]
-    fn from_usize(value: usize) -> Option<Self> {
-        Self::try_from(value).ok()
-    }
-}
-
-impl Index for i64 {
-    #[inline]
-    fn to_usize(&self) -> usize {
-        *self as usize
-    }
-
-    #[inline]
-    fn from_usize(value: usize) -> Option<Self> {
-        Self::try_from(value).ok()
-    }
-}
-
-impl Index for u32 {
-    #[inline]
-    fn to_usize(&self) -> usize {
-        *self as usize
-    }
-
-    #[inline]
-    fn from_usize(value: usize) -> Option<Self> {
-        Self::try_from(value).ok()
-    }
+macro_rules! index {
+    ($t:ty) => {
+        impl Index for $t {
+            #[inline]
+            fn to_usize(&self) -> usize {
+                *self as usize
+            }
+
+            #[inline]
+            fn from_usize(value: usize) -> Option<Self> {
+                Self::try_from(value).ok()
+            }
+        }
+    };
 }
 
-impl Index for u64 {
-    #[inline]
-    fn to_usize(&self) -> usize {
-        *self as usize
-    }
-
-    #[inline]
-    fn from_usize(value: usize) -> Option<Self> {
-        Self::try_from(value).ok()
-    }
-}
+index!(i8);
+index!(i16);
+index!(i32);
+index!(i64);
+index!(u8);
+index!(u16);
+index!(u32);
+index!(u64);
 
 /// Range of [`Index`], equivalent to `(a..b)`.
 /// `Step` is unstable in Rust, which does not allow us to implement (a..b) for [`Index`].

tests/it/compute/comparison.rs

@@ -1,7 +1,7 @@
 use arrow2::array::*;
 use arrow2::compute::comparison::boolean::*;
-use arrow2::datatypes::TimeUnit;
 use arrow2::datatypes::{DataType::*, IntervalUnit};
+use arrow2::datatypes::{IntegerType, TimeUnit};
 use arrow2::scalar::new_scalar;
 
 #[test]
@@ -41,6 +41,7 @@ fn consistency() {
         Duration(TimeUnit::Millisecond),
         Duration(TimeUnit::Microsecond),
         Duration(TimeUnit::Nanosecond),
+        Dictionary(IntegerType::Int32, Box::new(LargeBinary), false),
     ];
 
     // array <> array
@@ -58,11 +59,11 @@ fn consistency() {
     datatypes.into_iter().for_each(|d1| {
         let array = new_null_array(d1.clone(), 10);
         let scalar = new_scalar(array.as_ref(), 0);
-        if can_eq(&d1) {
+        if can_eq_scalar(&d1) {
             eq_scalar(array.as_ref(), scalar.as_ref());
         }
-        if can_lt_eq(&d1) {
-            lt_eq(array.as_ref(), array.as_ref());
+        if can_lt_eq_scalar(&d1) {
+            lt_eq_scalar(array.as_ref(), scalar.as_ref());
         }
     });
 }