feat: Add dt.replace

crates/polars-plan/src/dsl/dt.rs

@@ -331,4 +331,34 @@ impl DateLikeNameSpace {
             TemporalFunction::TotalNanoseconds,
         ))
     }
+
+    /// Replace the time units of a value
+    #[allow(clippy::too_many_arguments)]
+    pub fn replace(
+        self,
+        year: Expr,
+        month: Expr,
+        day: Expr,
+        hour: Expr,
+        minute: Expr,
+        second: Expr,
+        microsecond: Expr,
+        ambiguous: Expr,
+    ) -> Expr {
+        self.0.map_many_private(
+            FunctionExpr::TemporalExpr(TemporalFunction::Replace),
+            &[
+                year,
+                month,
+                day,
+                hour,
+                minute,
+                second,
+                microsecond,
+                ambiguous,
+            ],
+            false,
+            None,
+        )
+    }
 }

crates/polars-plan/src/dsl/function_expr/datetime.rs

@@ -8,6 +8,8 @@ use polars_time::base_utc_offset as base_utc_offset_fn;
 use polars_time::dst_offset as dst_offset_fn;
 #[cfg(feature = "offset_by")]
 use polars_time::impl_offset_by;
+#[cfg(any(feature = "dtype-date", feature = "dtype-datetime"))]
+use polars_time::replace::{replace_date, replace_datetime};
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
 
@@ -62,6 +64,7 @@ pub enum TemporalFunction {
     #[cfg(feature = "timezones")]
     DSTOffset,
     Round,
+    Replace,
     #[cfg(feature = "timezones")]
     ReplaceTimeZone(Option<TimeZone>, NonExistent),
     Combine(TimeUnit),
@@ -117,6 +120,7 @@ impl TemporalFunction {
             #[cfg(feature = "timezones")]
             DSTOffset => mapper.with_dtype(DataType::Duration(TimeUnit::Milliseconds)),
             Round => mapper.with_same_dtype(),
+            Replace => mapper.with_same_dtype(),
             #[cfg(feature = "timezones")]
             ReplaceTimeZone(tz, _non_existent) => mapper.map_datetime_dtype_timezone(tz.as_ref()),
             DatetimeFunction {
@@ -187,6 +191,7 @@ impl Display for TemporalFunction {
             #[cfg(feature = "timezones")]
             DSTOffset => "dst_offset",
             Round => "round",
+            Replace => "replace",
             #[cfg(feature = "timezones")]
             ReplaceTimeZone(_, _) => "replace_time_zone",
             DatetimeFunction { .. } => return write!(f, "dt.datetime"),
@@ -555,3 +560,46 @@ pub(super) fn round(s: &[Column]) -> PolarsResult<Column> {
         dt => polars_bail!(opq = round, got = dt, expected = "date/datetime"),
     })
 }
+
+pub(super) fn replace(s: &[Column]) -> PolarsResult<Column> {
+    let time_series = &s[0];
+    let s_year = &s[1].strict_cast(&DataType::Int32)?;
+    let s_month = &s[2].strict_cast(&DataType::Int8)?;
+    let s_day = &s[3].strict_cast(&DataType::Int8)?;
+    let year = s_year.i32()?;
+    let month = s_month.i8()?;
+    let day = s_day.i8()?;
+
+    match time_series.dtype() {
+        DataType::Datetime(_, _) => {
+            let s_hour = &s[4].strict_cast(&DataType::Int8)?;
+            let s_minute = &s[5].strict_cast(&DataType::Int8)?;
+            let s_second = &s[6].strict_cast(&DataType::Int8)?;
+            let s_microsecond = &s[7].strict_cast(&DataType::Int32)?;
+            let hour = s_hour.i8()?;
+            let minute = s_minute.i8()?;
+            let second = s_second.i8()?;
+            let nanosecond = &(s_microsecond.i32()? * 1_000);
+            let s_ambiguous = &s[8].strict_cast(&DataType::String)?;
+            let ambiguous = s_ambiguous.str()?;
+
+            let out = replace_datetime(
+                time_series.datetime().unwrap(),
+                year,
+                month,
+                day,
+                hour,
+                minute,
+                second,
+                nanosecond,
+                ambiguous,
+            );
+            out.map(|s| s.into_column())
+        },
+        DataType::Date => {
+            let out = replace_date(time_series.date().unwrap(), year, month, day);
+            out.map(|s| s.into_column())
+        },
+        dt => polars_bail!(opq = round, got = dt, expected = "date/datetime"),
+    }
+}

crates/polars-plan/src/dsl/function_expr/temporal.rs

@@ -58,6 +58,7 @@ impl From<TemporalFunction> for SpecialEq<Arc<dyn ColumnsUdf>> {
             #[cfg(feature = "timezones")]
             DSTOffset => map!(datetime::dst_offset),
             Round => map_as_slice!(datetime::round),
+            Replace => map_as_slice!(datetime::replace),
             #[cfg(feature = "timezones")]
             ReplaceTimeZone(tz, non_existent) => {
                 map_as_slice!(dispatch::replace_time_zone, tz.as_deref(), non_existent)
@@ -73,14 +74,12 @@ impl From<TemporalFunction> for SpecialEq<Arc<dyn ColumnsUdf>> {
     }
 }
 
+#[cfg(feature = "dtype-datetime")]
 pub(super) fn datetime(
     s: &[Column],
     time_unit: &TimeUnit,
     time_zone: Option<&str>,
 ) -> PolarsResult<Column> {
-    use polars_core::export::chrono::NaiveDate;
-    use polars_core::utils::CustomIterTools;
-
     let col_name = PlSmallStr::from_static("datetime");
 
     if s.iter().any(|s| s.is_empty()) {
@@ -123,91 +122,53 @@ pub(super) fn datetime(
     }
     let year = year.i32()?;
 
-    let mut month = month.cast(&DataType::UInt32)?;
+    let mut month = month.cast(&DataType::Int8)?;
     if month.len() < max_len {
         month = month.new_from_index(0, max_len);
     }
-    let month = month.u32()?;
+    let month = month.i8()?;
 
-    let mut day = day.cast(&DataType::UInt32)?;
+    let mut day = day.cast(&DataType::Int8)?;
     if day.len() < max_len {
         day = day.new_from_index(0, max_len);
     }
-    let day = day.u32()?;
+    let day = day.i8()?;
 
-    let mut hour = hour.cast(&DataType::UInt32)?;
+    let mut hour = hour.cast(&DataType::Int8)?;
     if hour.len() < max_len {
         hour = hour.new_from_index(0, max_len);
     }
-    let hour = hour.u32()?;
+    let hour = hour.i8()?;
 
-    let mut minute = minute.cast(&DataType::UInt32)?;
+    let mut minute = minute.cast(&DataType::Int8)?;
     if minute.len() < max_len {
         minute = minute.new_from_index(0, max_len);
     }
-    let minute = minute.u32()?;
+    let minute = minute.i8()?;
 
-    let mut second = second.cast(&DataType::UInt32)?;
+    let mut second = second.cast(&DataType::Int8)?;
     if second.len() < max_len {
         second = second.new_from_index(0, max_len);
     }
-    let second = second.u32()?;
+    let second = second.i8()?;
 
-    let mut microsecond = microsecond.cast(&DataType::UInt32)?;
-    if microsecond.len() < max_len {
-        microsecond = microsecond.new_from_index(0, max_len);
+    let mut nanosecond = microsecond.cast(&DataType::Int32)? * 1_000;
+    if nanosecond.len() < max_len {
+        nanosecond = nanosecond.new_from_index(0, max_len);
     }
-    let microsecond = microsecond.u32()?;
+    let nanosecond = nanosecond.i32()?;
+
     let mut _ambiguous = ambiguous.cast(&DataType::String)?;
     if _ambiguous.len() < max_len {
         _ambiguous = _ambiguous.new_from_index(0, max_len);
     }
-    let _ambiguous = _ambiguous.str()?;
-
-    let ca: Int64Chunked = year
-        .into_iter()
-        .zip(month)
-        .zip(day)
-        .zip(hour)
-        .zip(minute)
-        .zip(second)
-        .zip(microsecond)
-        .map(|((((((y, m), d), h), mnt), s), us)| {
-            if let (Some(y), Some(m), Some(d), Some(h), Some(mnt), Some(s), Some(us)) =
-                (y, m, d, h, mnt, s, us)
-            {
-                NaiveDate::from_ymd_opt(y, m, d)
-                    .and_then(|nd| nd.and_hms_micro_opt(h, mnt, s, us))
-                    .map(|ndt| match time_unit {
-                        TimeUnit::Milliseconds => ndt.and_utc().timestamp_millis(),
-                        TimeUnit::Microseconds => ndt.and_utc().timestamp_micros(),
-                        TimeUnit::Nanoseconds => ndt.and_utc().timestamp_nanos_opt().unwrap(),
-                    })
-            } else {
-                None
-            }
-        })
-        .collect_trusted();
-
-    let ca = match time_zone {
-        #[cfg(feature = "timezones")]
-        Some(_) => {
-            let mut ca = ca.into_datetime(*time_unit, None);
-            ca = replace_time_zone(&ca, time_zone, _ambiguous, NonExistent::Raise)?;
-            ca
-        },
-        _ => {
-            assert!(
-                time_zone.is_none(),
-                "cannot make use of the `time_zone` argument without the 'timezones' feature enabled."
-            );
-            ca.into_datetime(*time_unit, None)
-        },
-    };
+    let ambiguous = _ambiguous.str()?;
 
-    let mut s = ca.into_column();
-    s.rename(col_name);
-    Ok(s)
+    let ca = DatetimeChunked::new_from_parts(
+        year, month, day, hour, minute, second, nanosecond, ambiguous, time_unit, time_zone,
+        col_name,
+    );
+    ca.map(|s| s.into_column())
 }
 
 pub(super) fn combine(s: &[Column], tu: TimeUnit) -> PolarsResult<Column> {

crates/polars-python/src/expr/datetime.rs

@@ -99,6 +99,33 @@ impl PyExpr {
         self.inner.clone().dt().round(every.inner).into()
     }
 
+    fn dt_replace(
+        &self,
+        year: Self,
+        month: Self,
+        day: Self,
+        hour: Self,
+        minute: Self,
+        second: Self,
+        microsecond: Self,
+        ambiguous: Self,
+    ) -> Self {
+        self.inner
+            .clone()
+            .dt()
+            .replace(
+                year.inner,
+                month.inner,
+                day.inner,
+                hour.inner,
+                minute.inner,
+                second.inner,
+                microsecond.inner,
+                ambiguous.inner,
+            )
+            .into()
+    }
+
     fn dt_combine(&self, time: Self, time_unit: Wrap<TimeUnit>) -> Self {
         self.inner
             .clone()

crates/polars-python/src/lazyframe/visitor/expr_nodes.rs

@@ -252,6 +252,7 @@ pub enum PyTemporalFunction {
     BaseUtcOffset,
     DSTOffset,
     Round,
+    Replace,
     ReplaceTimeZone,
     Combine,
     DatetimeFunction,
@@ -1024,6 +1025,7 @@ pub(crate) fn into_py(py: Python<'_>, expr: &AExpr) -> PyResult<PyObject> {
                     #[cfg(feature = "timezones")]
                     TemporalFunction::DSTOffset => (PyTemporalFunction::DSTOffset,).into_py_any(py),
                     TemporalFunction::Round => (PyTemporalFunction::Round,).into_py_any(py),
+                    TemporalFunction::Replace => (PyTemporalFunction::Replace).into_py_any(py),
                     #[cfg(feature = "timezones")]
                     TemporalFunction::ReplaceTimeZone(time_zone, non_existent) => (
                         PyTemporalFunction::ReplaceTimeZone,

crates/polars-time/src/chunkedarray/date.rs

@@ -1,4 +1,6 @@
-use arrow::temporal_conversions::{MILLISECONDS, SECONDS_IN_DAY};
+use arrow::temporal_conversions::{EPOCH_DAYS_FROM_CE, MILLISECONDS, SECONDS_IN_DAY};
+use polars_core::export::chrono::{Datelike, NaiveDate};
+use polars_core::utils::CustomIterTools;
 
 use super::*;
 
@@ -74,6 +76,30 @@ pub trait DateMethods: AsDate {
     }
 
     fn parse_from_str_slice(name: PlSmallStr, v: &[&str], fmt: &str) -> DateChunked;
+
+    /// Construct a date ChunkedArray from individual time components.
+    fn new_from_parts(
+        year: &Int32Chunked,
+        month: &Int8Chunked,
+        day: &Int8Chunked,
+        name: PlSmallStr,
+    ) -> PolarsResult<DateChunked> {
+        let mut ca: Int32Chunked = year
+            .into_iter()
+            .zip(month)
+            .zip(day)
+            .map(|((y, m), d)| {
+                if let (Some(y), Some(m), Some(d)) = (y, m, d) {
+                    NaiveDate::from_ymd_opt(y, m as u32, d as u32)
+                        .map(|t| t.num_days_from_ce() - EPOCH_DAYS_FROM_CE)
+                } else {
+                    None
+                }
+            })
+            .collect_trusted();
+        ca.rename(name);
+        Ok(ca.into_date())
+    }
 }
 
 impl DateMethods for DateChunked {