datafusion_spark/function/math/
expm1.rs

1// Licensed to the Apache Software Foundation (ASF) under one
2// or more contributor license agreements.  See the NOTICE file
3// distributed with this work for additional information
4// regarding copyright ownership.  The ASF licenses this file
5// to you under the Apache License, Version 2.0 (the
6// "License"); you may not use this file except in compliance
7// with the License.  You may obtain a copy of the License at
8//
9//   http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing,
12// software distributed under the License is distributed on an
13// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14// KIND, either express or implied.  See the License for the
15// specific language governing permissions and limitations
16// under the License.
17
18use crate::function::error_utils::unsupported_data_type_exec_err;
19use arrow::array::{ArrayRef, AsArray};
20use arrow::datatypes::{DataType, Float64Type};
21use datafusion_common::utils::take_function_args;
22use datafusion_common::{Result, ScalarValue};
23use datafusion_expr::{
24    ColumnarValue, ScalarFunctionArgs, ScalarUDFImpl, Signature, Volatility,
25};
26use std::any::Any;
27use std::sync::Arc;
28
29/// <https://spark.apache.org/docs/latest/api/sql/index.html#expm1>
30#[derive(Debug, PartialEq, Eq, Hash)]
31pub struct SparkExpm1 {
32    signature: Signature,
33}
34
35impl Default for SparkExpm1 {
36    fn default() -> Self {
37        Self::new()
38    }
39}
40
41impl SparkExpm1 {
42    pub fn new() -> Self {
43        Self {
44            signature: Signature::exact(vec![DataType::Float64], Volatility::Immutable),
45        }
46    }
47}
48
49impl ScalarUDFImpl for SparkExpm1 {
50    fn as_any(&self) -> &dyn Any {
51        self
52    }
53
54    fn name(&self) -> &str {
55        "expm1"
56    }
57
58    fn signature(&self) -> &Signature {
59        &self.signature
60    }
61
62    fn return_type(&self, _arg_types: &[DataType]) -> Result<DataType> {
63        Ok(DataType::Float64)
64    }
65
66    fn invoke_with_args(&self, args: ScalarFunctionArgs) -> Result<ColumnarValue> {
67        let [arg] = take_function_args(self.name(), args.args)?;
68        match arg {
69            ColumnarValue::Scalar(ScalarValue::Float64(value)) => Ok(
70                ColumnarValue::Scalar(ScalarValue::Float64(value.map(|x| x.exp_m1()))),
71            ),
72            ColumnarValue::Array(array) => match array.data_type() {
73                DataType::Float64 => Ok(ColumnarValue::Array(Arc::new(
74                    array
75                        .as_primitive::<Float64Type>()
76                        .unary::<_, Float64Type>(|x| x.exp_m1()),
77                )
78                    as ArrayRef)),
79                other => Err(unsupported_data_type_exec_err(
80                    "expm1",
81                    format!("{}", DataType::Float64).as_str(),
82                    other,
83                )),
84            },
85            other => Err(unsupported_data_type_exec_err(
86                "expm1",
87                format!("{}", DataType::Float64).as_str(),
88                &other.data_type(),
89            )),
90        }
91    }
92}
datafusion_spark/function/math/expm1.rs

datafusion_spark/function/math/
expm1.rs
