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_ $from_ver>]::ffi::ArrowSchema,
62                                        ArrowSchema,
63                                    >(ffi_field)};
64
65                                    // Create series
66                                    ffi_chunk.push((ffi_array, ffi_field));
67                                }
68
69                                ffi.push((name, ffi_chunk));
70                            }
71
72                            ffi
73                        }
74                    })
75                }
76            }
77        }
78    };
79}
80#[cfg(feature = "polars_0_44")]
81polars_to_ffi!("0_44");
82
83#[cfg(feature = "polars_0_45")]
84polars_to_ffi!("0_45");
85
86#[cfg(feature = "polars_0_46")]
87polars_to_ffi!("0_46");
88
89#[cfg(feature = "polars_0_47")]
90polars_to_ffi!("0_47");
91
92#[cfg(feature = "polars_0_48")]
93polars_to_ffi!("0_48");
94
95#[cfg(feature = "polars_0_49")]
96polars_to_ffi!("0_49");
97
98#[cfg(feature = "polars_0_50")]
99polars_to_ffi!("0_50");
100
101#[cfg(feature = "polars_0_51")]
102polars_to_ffi!("0_51");
103
104macro_rules! polars_to_ffi {
105    ($from_ver:literal) => {
106        paste! {
107            impl Interchange {
108                #[doc = "Move Polars version `" $from_ver "` to the Arrow data interchange format."]
109                pub fn [<from_polars_ $from_ver>](df: [<polars_crate_ $from_ver>]::frame::DataFrame) -> Result<Self, InterchangeError> {
110                    Ok(Self {
111                        chunks_aligned: !df.should_rechunk(),
112                        ffi: {
113                            // Number of columns
114                            let num_cols = df.width();
115
116                            // Prepare ffi series vec
117                            let mut ffi = Vec::with_capacity(num_cols);
118
119                            // Get the series from the df
120                            let series: Vec<[<polars_crate_ $from_ver>]::series::Series> = df.take_columns();
121
122                            for s in series {
123                                // Get arrow-type fields
124                                let field = &s
125                                    .field()
126                                    .to_arrow([<polars_crate_ $from_ver>]::datatypes::CompatLevel::newest());
127
128                                // Get name of column
129                                let name = s.name().to_string();
130
131                                // Get number of chunks in each column
132                                let n_chunks = s.n_chunks();
133
134                                // Prepare chunk vec
135                                let mut ffi_chunk = Vec::with_capacity(num_cols);
136
137                                for c in 0..n_chunks {
138
139                                    // Get ffi array
140                                    let ffi_array = [<polars_arrow_ $from_ver>]::ffi::export_array_to_c(
141                                        s.to_arrow(c, [<polars_crate_ $from_ver>]::datatypes::CompatLevel::newest()),
142                                    );
143
144                                    // Get ffi field
145                                    let ffi_field = [<polars_arrow_ $from_ver>]::ffi::export_field_to_c(field);
146
147                                    // Convert ffi array from polars-arrow to this crate's version of ArrowArray
148                                    let ffi_array = unsafe { transmute::<
149                                        [<polars_arrow_ $from_ver>]::ffi::ArrowArray,
150                                        ArrowArray,
151                                    >(ffi_array)};
152
153                                    // Convert ffi field from polars-arrow to this crate's version of ArrowField
154                                    let ffi_field = unsafe{transmute::<
155                                        [<polars_arrow_ $from_ver>]::ffi::ArrowSchema,
156                                        ArrowSchema,
157                                    >(ffi_field)};
158
159                                    // Create series
160                                    ffi_chunk.push((ffi_array, ffi_field));
161                                }
162
163                                ffi.push((name, ffi_chunk));
164                            }
165
166                            ffi
167                        }
168                    })
169                }
170            }
171        }
172    };
173}
174
175#[cfg(feature = "polars_0_42")]
176polars_to_ffi!("0_42");
177
178#[cfg(feature = "polars_0_43")]
179polars_to_ffi!("0_43");
180
181macro_rules! polars_to_ffi {
182    ($from_ver:literal) => {
183        paste! {
184            impl Interchange {
185                #[doc = "Move Polars version `" $from_ver "` to the Arrow data interchange format."]
186                pub fn [<from_polars_ $from_ver>](df: [<polars_crate_ $from_ver>]::frame::DataFrame) -> Result<Self, InterchangeError> {
187                    Ok(Self {
188                        chunks_aligned: !df.should_rechunk(),
189                        ffi: {
190                            // Number of columns
191                            let num_cols = df.width();
192
193                            // Prepare ffi series vec
194                            let mut ffi = Vec::with_capacity(num_cols);
195
196                            // Get column names to remove them one by one
197                            let names = df.get_column_names();
198
199                            // Get the series from the df
200                            let series: Vec<[<polars_crate_ $from_ver>]::series::Series> = df.select_series(names)?;
201
202                            for s in series {
203                                // Get arrow-type fields
204                                let field = &s
205                                    .field()
206                                    .to_arrow(false);
207
208                                // Get name of column
209                                let name = s.name().to_string();
210
211                                // Get number of chunks in each column
212                                let n_chunks = s.n_chunks();
213
214                                // Prepare chunk vec
215                                let mut ffi_chunk = Vec::with_capacity(num_cols);
216
217                                for c in 0..n_chunks {
218
219                                    // Get ffi array
220                                    let ffi_array = [<polars_arrow_ $from_ver>]::ffi::export_array_to_c(
221                                        s.to_arrow(c, false),
222                                    );
223
224                                    // Get ffi field
225                                    let ffi_field = [<polars_arrow_ $from_ver>]::ffi::export_field_to_c(field);
226
227                                    // Convert ffi array from polars-arrow to this crate's version of ArrowArray
228                                    let ffi_array = unsafe { transmute::<
229                                        [<polars_arrow_ $from_ver>]::ffi::ArrowArray,
230                                        ArrowArray,
231                                    >(ffi_array)};
232
233                                    // Convert ffi field from polars-arrow to this crate's version of ArrowField
234                                    let ffi_field = unsafe{transmute::<
235                                        [<polars_arrow_ $from_ver>]::ffi::ArrowSchema,
236                                        ArrowSchema,
237                                    >(ffi_field)};
238
239                                    // Create series
240                                    ffi_chunk.push((ffi_array, ffi_field));
241                                }
242
243                                ffi.push((name, ffi_chunk));
244                            }
245
246                            ffi
247                        }
248                    })
249                }
250            }
251        }
252    };
253}
254
255#[cfg(feature = "polars_0_40")]
256polars_to_ffi!("0_40");
257
258#[cfg(feature = "polars_0_41")]
259polars_to_ffi!("0_41");