Add DataType::Time

This adds a Logical Type Time to Series.
Arrow time32/time64 will be converted to
arrow time64(nanosecond) when converted to
polars.

polars/Cargo.toml

@@ -103,6 +103,7 @@ private = []
 dtype-full = [
     "dtype-date",
     "dtype-datetime",
+    "dtype-time",
     "dtype-i8",
     "dtype-i16",
     "dtype-u8",
@@ -116,8 +117,9 @@ dtype-slim = [
 ]
 
 # opt-in datatypes for Series
-dtype-date = ["polars-core/dtype-date", "polars-lazy/dtype-date"]
-dtype-datetime= ["polars-core/dtype-datetime", "polars-lazy/dtype-datetime"]
+dtype-date = ["polars-core/dtype-date", "polars-lazy/dtype-date", "polars-io/dtype-date"]
+dtype-datetime= ["polars-core/dtype-datetime", "polars-lazy/dtype-datetime", "polars-io/dtype-datetime"]
+dtype-time= ["polars-core/dtype-time", "polars-io/dtype-time"]
 dtype-i8 = ["polars-core/dtype-i8", "polars-lazy/dtype-i8"]
 dtype-i16 = ["polars-core/dtype-i16", "polars-lazy/dtype-i16"]
 dtype-u8 = ["polars-core/dtype-u8", "polars-lazy/dtype-u8"]

polars/polars-core/Cargo.toml

@@ -80,6 +80,7 @@ moment = []
 # opt-in datatypes for Series
 dtype-date = ["temporal"]
 dtype-datetime= ["temporal"]
+dtype-time = ["temporal"]
 dtype-i8 = []
 dtype-i16 = []
 dtype-u8 = []

polars/polars-core/src/chunked_array/cast.rs

@@ -20,6 +20,8 @@ fn cast_impl(name: &str, chunks: &[ArrayRef], dtype: &DataType) -> Result<Series
     use DataType::*;
     let out = match dtype {
         Date | Datetime => out.into_date(),
+        #[cfg(feature = "dtype-time")]
+        Time => out.into_time(),
         _ => out,
     };
 

polars/polars-core/src/chunked_array/kernels/temporal.rs

@@ -1,7 +1,11 @@
-use crate::chunked_array::temporal::conversions_utils::*;
+//! macros that define kernels for extracting
+//! `week`, `weekday`, `year`, `hour` etc. from primitive arrays.
 use crate::prelude::*;
 use arrow::array::{ArrayRef, PrimitiveArray};
 use arrow::compute::arity::unary;
+#[cfg(feature = "dtype-time")]
+use arrow::temporal_conversions::time64ns_to_time;
+use arrow::temporal_conversions::{date32_to_datetime, timestamp_ms_to_datetime};
 use chrono::{Datelike, NaiveDate, NaiveDateTime, Timelike};
 use std::sync::Arc;
 
@@ -42,115 +46,164 @@ macro_rules! to_temporal_unit {
         }
     };
 }
+#[cfg(feature = "dtype-date")]
 to_temporal_unit!(
     date_to_week,
     week,
-    date_as_datetime,
+    date32_to_datetime,
     i32,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-date")]
 to_temporal_unit!(
     date_to_weekday,
     p_weekday,
-    date_as_datetime,
+    date32_to_datetime,
     i32,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-date")]
 to_temporal_unit!(
     date_to_year,
     year,
-    date_as_datetime,
+    date32_to_datetime,
     i32,
     ArrowDataType::Int32
 );
+#[cfg(feature = "dtype-date")]
 to_temporal_unit!(
     date_to_month,
     month,
-    date_as_datetime,
+    date32_to_datetime,
     i32,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-date")]
 to_temporal_unit!(
     date_to_day,
     day,
-    date_as_datetime,
+    date32_to_datetime,
     i32,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-date")]
 to_temporal_unit!(
     date_to_ordinal,
     ordinal,
-    date_as_datetime,
+    date32_to_datetime,
     i32,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_week,
     week,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_weekday,
     p_weekday,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_year,
     year,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::Int32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_month,
     month,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_day,
     day,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_hour,
     hour,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_minute,
     minute,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_second,
     second,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_nanosecond,
     nanosecond,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
     i64,
     ArrowDataType::UInt32
 );
+#[cfg(feature = "dtype-datetime")]
 to_temporal_unit!(
     datetime_to_ordinal,
     ordinal,
-    datetime_as_datetime,
+    timestamp_ms_to_datetime,
+    i64,
+    ArrowDataType::UInt32
+);
+
+#[cfg(feature = "dtype-time")]
+to_temporal_unit!(
+    time_to_hour,
+    hour,
+    time64ns_to_time,
+    i64,
+    ArrowDataType::UInt32
+);
+#[cfg(feature = "dtype-time")]
+to_temporal_unit!(
+    time_to_minute,
+    minute,
+    time64ns_to_time,
+    i64,
+    ArrowDataType::UInt32
+);
+#[cfg(feature = "dtype-time")]
+to_temporal_unit!(
+    time_to_second,
+    second,
+    time64ns_to_time,
+    i64,
+    ArrowDataType::UInt32
+);
+#[cfg(feature = "dtype-time")]
+to_temporal_unit!(
+    time_to_nanosecond,
+    nanosecond,
+    time64ns_to_time,
     i64,
     ArrowDataType::UInt32
 );

polars/polars-core/src/chunked_array/logical/mod.rs

@@ -1,7 +1,8 @@
 mod date;
 mod datetime;
+mod time;
 
-pub use {date::*, datetime::*};
+pub use {date::*, datetime::*, time::*};
 
 use crate::prelude::*;
 use std::marker::PhantomData;

polars/polars-core/src/chunked_array/logical/time.rs

@@ -0,0 +1,22 @@
+use super::*;
+use crate::prelude::*;
+
+pub type TimeChunked = Logical<TimeType, Int64Type>;
+
+impl From<Int64Chunked> for TimeChunked {
+    fn from(ca: Int64Chunked) -> Self {
+        TimeChunked::new(ca)
+    }
+}
+
+impl Int64Chunked {
+    pub fn into_time(self) -> TimeChunked {
+        TimeChunked::new(self)
+    }
+}
+
+impl LogicalType for TimeChunked {
+    fn dtype(&self) -> &'static DataType {
+        &DataType::Time
+    }
+}