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