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fix: Avoid precision loss for atan2 with integer args #22516

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fix: Avoid precision loss for atan2 with integer args #22516

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56 changes: 1 addition & 55 deletions datafusion/functions/benches/atan2.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -17,7 +17,7 @@

extern crate criterion;

use arrow::datatypes::{DataType, Field, Float32Type, Float64Type};
use arrow::datatypes::{DataType, Field, Float64Type};
use arrow::util::bench_util::create_primitive_array;
use criterion::{Criterion, criterion_group, criterion_main};
use datafusion_common::ScalarValue;
Expand All @@ -32,34 +32,6 @@ fn criterion_benchmark(c: &mut Criterion) {
let config_options = Arc::new(ConfigOptions::default());

for size in [1024, 4096, 8192] {
let y_f32 = Arc::new(create_primitive_array::<Float32Type>(size, 0.2));
let x_f32 = Arc::new(create_primitive_array::<Float32Type>(size, 0.2));
let f32_args = vec![ColumnarValue::Array(y_f32), ColumnarValue::Array(x_f32)];
let f32_arg_fields = f32_args
.iter()
.enumerate()
.map(|(idx, arg)| {
Field::new(format!("arg_{idx}"), arg.data_type(), true).into()
})
.collect::<Vec<_>>();
let return_field_f32 = Field::new("f", DataType::Float32, true).into();

c.bench_function(&format!("atan2 f32 array: {size}"), |b| {
b.iter(|| {
black_box(
atan2_fn
.invoke_with_args(ScalarFunctionArgs {
args: f32_args.clone(),
arg_fields: f32_arg_fields.clone(),
number_rows: size,
return_field: Arc::clone(&return_field_f32),
config_options: Arc::clone(&config_options),
})
.unwrap(),
)
})
});

let y_f64 = Arc::new(create_primitive_array::<Float64Type>(size, 0.2));
let x_f64 = Arc::new(create_primitive_array::<Float64Type>(size, 0.2));
let f64_args = vec![ColumnarValue::Array(y_f64), ColumnarValue::Array(x_f64)];
Expand Down Expand Up @@ -89,32 +61,6 @@ fn criterion_benchmark(c: &mut Criterion) {
});
}

let scalar_f32_args = vec![
ColumnarValue::Scalar(ScalarValue::Float32(Some(1.0))),
ColumnarValue::Scalar(ScalarValue::Float32(Some(2.0))),
];
let scalar_f32_arg_fields = vec![
Field::new("a", DataType::Float32, false).into(),
Field::new("b", DataType::Float32, false).into(),
];
let return_field_f32 = Field::new("f", DataType::Float32, false).into();

c.bench_function("atan2 f32 scalar", |b| {
b.iter(|| {
black_box(
atan2_fn
.invoke_with_args(ScalarFunctionArgs {
args: scalar_f32_args.clone(),
arg_fields: scalar_f32_arg_fields.clone(),
number_rows: 1,
return_field: Arc::clone(&return_field_f32),
config_options: Arc::clone(&config_options),
})
.unwrap(),
)
})
});

let scalar_f64_args = vec![
ColumnarValue::Scalar(ScalarValue::Float64(Some(1.0))),
ColumnarValue::Scalar(ScalarValue::Float64(Some(2.0))),
Expand Down
79 changes: 23 additions & 56 deletions datafusion/functions/src/macros.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -345,8 +345,8 @@ macro_rules! make_math_unary_udf {

/// Macro to create a binary math UDF.
///
/// A binary math function takes two arguments of types Float32 or Float64,
/// applies a binary floating function to the argument, and returns a value of the same type.
/// A binary math function takes two numeric arguments, coerces them to Float64,
/// applies a binary floating function to the arguments, and returns Float64.
///
/// $UDF: the name of the UDF struct that implements `ScalarUDFImpl`
/// $NAME: the name of the function
Expand All @@ -362,10 +362,9 @@ macro_rules! make_math_binary_udf {
use std::sync::Arc;

use arrow::array::{ArrayRef, AsArray};
use arrow::datatypes::{DataType, Float32Type, Float64Type};
use arrow::datatypes::{DataType, Float64Type};
use datafusion_common::utils::take_function_args;
use datafusion_common::{Result, ScalarValue, internal_err};
use datafusion_expr::TypeSignature;
use datafusion_expr::sort_properties::{ExprProperties, SortProperties};
use datafusion_expr::{
ColumnarValue, Documentation, ScalarFunctionArgs, ScalarUDFImpl,
Expand All @@ -381,11 +380,8 @@ macro_rules! make_math_binary_udf {
pub fn new() -> Self {
use DataType::*;
Self {
signature: Signature::one_of(
vec![
TypeSignature::Exact(vec![Float32, Float32]),
TypeSignature::Exact(vec![Float64, Float64]),
],
signature: Signature::exact(
vec![Float64, Float64],
Volatility::Immutable,
),
}
Expand All @@ -401,14 +397,8 @@ macro_rules! make_math_binary_udf {
&self.signature
}

fn return_type(&self, arg_types: &[DataType]) -> Result<DataType> {
let arg_type = &arg_types[0];

match arg_type {
DataType::Float32 => Ok(DataType::Float32),
// For other types (possible values float64/null/int), use Float64
_ => Ok(DataType::Float64),
}
fn return_type(&self, _arg_types: &[DataType]) -> Result<DataType> {
Ok(DataType::Float64)
}

fn output_ordering(
Expand All @@ -422,10 +412,7 @@ macro_rules! make_math_binary_udf {
&self,
args: ScalarFunctionArgs,
) -> Result<ColumnarValue> {
let ScalarFunctionArgs {
args, return_field, ..
} = args;
let return_type = return_field.data_type();
let ScalarFunctionArgs { args, .. } = args;
let [y, x] = take_function_args(self.name(), args)?;

match (y, x) {
Expand All @@ -434,21 +421,14 @@ macro_rules! make_math_binary_udf {
ColumnarValue::Scalar(x_scalar),
) => match (&y_scalar, &x_scalar) {
(y, x) if y.is_null() || x.is_null() => {
ColumnarValue::Scalar(ScalarValue::Null)
.cast_to(return_type, None)
Ok(ColumnarValue::Scalar(ScalarValue::Float64(None)))
}
(
ScalarValue::Float64(Some(yv)),
ScalarValue::Float64(Some(xv)),
) => Ok(ColumnarValue::Scalar(ScalarValue::Float64(Some(
f64::$BINARY_FUNC(*yv, *xv),
)))),
(
ScalarValue::Float32(Some(yv)),
ScalarValue::Float32(Some(xv)),
) => Ok(ColumnarValue::Scalar(ScalarValue::Float32(Some(
f32::$BINARY_FUNC(*yv, *xv),
)))),
_ => internal_err!(
"Unexpected scalar types for function {}: {:?}, {:?}",
self.name(),
Expand All @@ -458,38 +438,25 @@ macro_rules! make_math_binary_udf {
},
(y, x) => {
let args = ColumnarValue::values_to_arrays(&[y, x])?;
let arr: ArrayRef = match args[0].data_type() {
DataType::Float64 => {
match (args[0].data_type(), args[1].data_type()) {
(DataType::Float64, DataType::Float64) => {
let y = args[0].as_primitive::<Float64Type>();
let x = args[1].as_primitive::<Float64Type>();
let result =
arrow::compute::binary::<_, _, _, Float64Type>(
y,
x,
|y, x| f64::$BINARY_FUNC(y, x),
)?;
Arc::new(result) as _
}
DataType::Float32 => {
let y = args[0].as_primitive::<Float32Type>();
let x = args[1].as_primitive::<Float32Type>();
let result =
arrow::compute::binary::<_, _, _, Float32Type>(
y,
x,
|y, x| f32::$BINARY_FUNC(y, x),
)?;
Arc::new(result) as _
let result = arrow::compute::binary::<_, _, _, Float64Type>(
y,
x,
|y, x| f64::$BINARY_FUNC(y, x),
)?;

Ok(ColumnarValue::Array(Arc::new(result) as ArrayRef))
}
other => {
return internal_err!(
"Unsupported data type {other:?} for function {}",
(left, right) => {
internal_err!(
"Unexpected array types for function {}: {left:?}, {right:?}",
self.name()
);
)
}
};

Ok(ColumnarValue::Array(arr))
}
}
}
}
Expand Down
10 changes: 5 additions & 5 deletions datafusion/functions/src/math/monotonicity.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -262,11 +262,11 @@ Can be a constant, column, or function, and any combination of arithmetic operat
)
.with_sql_example(r#"```sql
> SELECT atan2(1, 1);
+------------+
| atan2(1,1) |
+------------+
| 0.7853982 |
+------------+
+--------------------+
| atan2(1,1) |
+--------------------+
| 0.7853981633974483 |
+--------------------+
```"#)
.build()
});
Expand Down
18 changes: 17 additions & 1 deletion datafusion/sqllogictest/test_files/scalar.slt
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Expand Up @@ -234,7 +234,23 @@ select round(atanh(a), 5), round(atanh(b), 5), round(atanh(c), 5) from small_flo
query RRR rowsort
select atan2(0, 1), atan2(1, 2), atan2(2, 2);
----
0 0.4636476 0.7853982
0 0.463647609001 0.785398163397

# atan2 always returns Float64, including integer, Float32, and NULL inputs
query TTTT
select
arrow_typeof(atan2(1, 1)),
arrow_typeof(atan2(arrow_cast(1.0, 'Float32'), arrow_cast(1.0, 'Float32'))),
arrow_typeof(atan2(null, null)),
arrow_typeof(atan2(null, 64));
----
Float64 Float64 Float64 Float64

# atan2 with integer inputs is computed in double precision
query B
select atan2(1, 1000000) = atan2(1.0, 1000000.0);
----
true

# atan2 scalar nulls
query R rowsort
Expand Down
10 changes: 5 additions & 5 deletions docs/source/user-guide/sql/scalar_functions.md
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Original file line number Diff line number Diff line change
Expand Up @@ -227,11 +227,11 @@ atan2(expression_y, expression_x)

```sql
> SELECT atan2(1, 1);
+------------+
| atan2(1,1) |
+------------+
| 0.7853982 |
+------------+
+--------------------+
| atan2(1,1) |
+--------------------+
| 0.7853981633974483 |
+--------------------+
```

### `atanh`
Expand Down
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