df_interchange/
from_polars.rs

1use paste::paste;
2use std::mem::transmute;
3
4use crate::{error::InterchangeError, ArrowArray, ArrowSchema, Interchange};
5
6macro_rules! polars_to_ffi {
7    ($from_ver:literal) => {
8        paste! {
9            impl Interchange {
10                #[doc = "Move Polars version `" $from_ver "` to the Arrow data interchange format."]
11                pub fn [<from_polars_ $from_ver>](df: [<polars_crate_ $from_ver>]::frame::DataFrame) -> Result<Self, InterchangeError> {
12                    Ok(Self {
13                        chunks_aligned: !df.should_rechunk(),
14                        ffi: {
15                            // Number of columns
16                            let num_cols = df.width();
17
18                            // Prepare ffi series vec
19                            let mut ffi = Vec::with_capacity(num_cols);
20
21                            // Get the columns from the df, as series
22                            let series: Vec<[<polars_crate_ $from_ver>]::series::Series> = df
23                                .take_columns()
24                                .into_iter()
25                                .map(|s| s.take_materialized_series())
26                                .collect();
27
28                            for s in series {
29                                // Get arrow-type fields
30                                let field = &s
31                                    .field()
32                                    .to_arrow([<polars_crate_ $from_ver>]::datatypes::CompatLevel::newest());
33
34                                // Get name of column
35                                let name = s.name().to_string();
36
37                                // Get number of chunks in each column
38                                let n_chunks = s.n_chunks();
39
40                                // Prepare chunk vec
41                                let mut ffi_chunk = Vec::with_capacity(num_cols);
42
43                                for c in 0..n_chunks {
44
45                                    // Get ffi array
46                                    let ffi_array = [<polars_arrow_ $from_ver>]::ffi::export_array_to_c(
47                                        s.to_arrow(c, [<polars_crate_ $from_ver>]::datatypes::CompatLevel::newest()),
48                                    );
49
50                                    // Get ffi field
51                                    let ffi_field = [<polars_arrow_ $from_ver>]::ffi::export_field_to_c(field);
52
53                                    // Convert ffi array from polars-arrow to this crate's version of ArrowArray
54                                    let ffi_array = unsafe { transmute::<
55                                        [<polars_arrow_ $from_ver>]::ffi::ArrowArray,
56                                        ArrowArray,
57                                    >(ffi_array)};
58
59                                    // Convert ffi field from polars-arrow to this crate's version of ArrowField
60                                    let ffi_field = unsafe{transmute::<
61                                        [<polars_arrow_ $from_ver>]::ffi::ArrowSchema,
62                                        ArrowSchema,
63                                    >(ffi_field)};
64
65                                    // Create series
66                                    ffi_chunk.push((ffi_array, ffi_field));
67                                }
68
69                                ffi.push((name, ffi_chunk));
70                            }
71
72                            ffi
73                        }
74                    })
75                }
76            }
77        }
78    };
79}
80#[cfg(feature = "polars_0_44")]
81polars_to_ffi!("0_44");
82
83#[cfg(feature = "polars_0_45")]
84polars_to_ffi!("0_45");
85
86#[cfg(feature = "polars_0_46")]
87polars_to_ffi!("0_46");
88
89#[cfg(feature = "polars_0_47")]
90polars_to_ffi!("0_47");
91
92#[cfg(feature = "polars_0_48")]
93polars_to_ffi!("0_48");
94
95#[cfg(feature = "polars_0_49")]
96polars_to_ffi!("0_49");
97
98#[cfg(feature = "polars_0_50")]
99polars_to_ffi!("0_50");
100
101macro_rules! polars_to_ffi {
102    ($from_ver:literal) => {
103        paste! {
104            impl Interchange {
105                #[doc = "Move Polars version `" $from_ver "` to the Arrow data interchange format."]
106                pub fn [<from_polars_ $from_ver>](df: [<polars_crate_ $from_ver>]::frame::DataFrame) -> Result<Self, InterchangeError> {
107                    Ok(Self {
108                        chunks_aligned: !df.should_rechunk(),
109                        ffi: {
110                            // Number of columns
111                            let num_cols = df.width();
112
113                            // Prepare ffi series vec
114                            let mut ffi = Vec::with_capacity(num_cols);
115
116                            // Get the series from the df
117                            let series: Vec<[<polars_crate_ $from_ver>]::series::Series> = df.take_columns();
118
119                            for s in series {
120                                // Get arrow-type fields
121                                let field = &s
122                                    .field()
123                                    .to_arrow([<polars_crate_ $from_ver>]::datatypes::CompatLevel::newest());
124
125                                // Get name of column
126                                let name = s.name().to_string();
127
128                                // Get number of chunks in each column
129                                let n_chunks = s.n_chunks();
130
131                                // Prepare chunk vec
132                                let mut ffi_chunk = Vec::with_capacity(num_cols);
133
134                                for c in 0..n_chunks {
135
136                                    // Get ffi array
137                                    let ffi_array = [<polars_arrow_ $from_ver>]::ffi::export_array_to_c(
138                                        s.to_arrow(c, [<polars_crate_ $from_ver>]::datatypes::CompatLevel::newest()),
139                                    );
140
141                                    // Get ffi field
142                                    let ffi_field = [<polars_arrow_ $from_ver>]::ffi::export_field_to_c(field);
143
144                                    // Convert ffi array from polars-arrow to this crate's version of ArrowArray
145                                    let ffi_array = unsafe { transmute::<
146                                        [<polars_arrow_ $from_ver>]::ffi::ArrowArray,
147                                        ArrowArray,
148                                    >(ffi_array)};
149
150                                    // Convert ffi field from polars-arrow to this crate's version of ArrowField
151                                    let ffi_field = unsafe{transmute::<
152                                        [<polars_arrow_ $from_ver>]::ffi::ArrowSchema,
153                                        ArrowSchema,
154                                    >(ffi_field)};
155
156                                    // Create series
157                                    ffi_chunk.push((ffi_array, ffi_field));
158                                }
159
160                                ffi.push((name, ffi_chunk));
161                            }
162
163                            ffi
164                        }
165                    })
166                }
167            }
168        }
169    };
170}
171
172#[cfg(feature = "polars_0_42")]
173polars_to_ffi!("0_42");
174
175#[cfg(feature = "polars_0_43")]
176polars_to_ffi!("0_43");
177
178macro_rules! polars_to_ffi {
179    ($from_ver:literal) => {
180        paste! {
181            impl Interchange {
182                #[doc = "Move Polars version `" $from_ver "` to the Arrow data interchange format."]
183                pub fn [<from_polars_ $from_ver>](df: [<polars_crate_ $from_ver>]::frame::DataFrame) -> Result<Self, InterchangeError> {
184                    Ok(Self {
185                        chunks_aligned: !df.should_rechunk(),
186                        ffi: {
187                            // Number of columns
188                            let num_cols = df.width();
189
190                            // Prepare ffi series vec
191                            let mut ffi = Vec::with_capacity(num_cols);
192
193                            // Get column names to remove them one by one
194                            let names = df.get_column_names();
195
196                            // Get the series from the df
197                            let series: Vec<[<polars_crate_ $from_ver>]::series::Series> = df.select_series(names)?;
198
199                            for s in series {
200                                // Get arrow-type fields
201                                let field = &s
202                                    .field()
203                                    .to_arrow(false);
204
205                                // Get name of column
206                                let name = s.name().to_string();
207
208                                // Get number of chunks in each column
209                                let n_chunks = s.n_chunks();
210
211                                // Prepare chunk vec
212                                let mut ffi_chunk = Vec::with_capacity(num_cols);
213
214                                for c in 0..n_chunks {
215
216                                    // Get ffi array
217                                    let ffi_array = [<polars_arrow_ $from_ver>]::ffi::export_array_to_c(
218                                        s.to_arrow(c, false),
219                                    );
220
221                                    // Get ffi field
222                                    let ffi_field = [<polars_arrow_ $from_ver>]::ffi::export_field_to_c(field);
223
224                                    // Convert ffi array from polars-arrow to this crate's version of ArrowArray
225                                    let ffi_array = unsafe { transmute::<
226                                        [<polars_arrow_ $from_ver>]::ffi::ArrowArray,
227                                        ArrowArray,
228                                    >(ffi_array)};
229
230                                    // Convert ffi field from polars-arrow to this crate's version of ArrowField
231                                    let ffi_field = unsafe{transmute::<
232                                        [<polars_arrow_ $from_ver>]::ffi::ArrowSchema,
233                                        ArrowSchema,
234                                    >(ffi_field)};
235
236                                    // Create series
237                                    ffi_chunk.push((ffi_array, ffi_field));
238                                }
239
240                                ffi.push((name, ffi_chunk));
241                            }
242
243                            ffi
244                        }
245                    })
246                }
247            }
248        }
249    };
250}
251
252#[cfg(feature = "polars_0_40")]
253polars_to_ffi!("0_40");
254
255#[cfg(feature = "polars_0_41")]
256polars_to_ffi!("0_41");