xref: /libCEED/rust/libceed/src/elem_restriction.rs (revision daaf13a462f999a7d367f3df68e0e3c34270722c)
1 // Copyright (c) 2017-2024, Lawrence Livermore National Security, LLC and other CEED contributors.
2 // All Rights Reserved. See the top-level LICENSE and NOTICE files for details.
3 //
4 // SPDX-License-Identifier: BSD-2-Clause
5 //
6 // This file is part of CEED:  http://github.com/ceed
7 
8 //! A Ceed ElemRestriction decomposes elements and groups the degrees of freedom
9 //! (dofs) according to the different elements they belong to.
10 
11 use crate::prelude::*;
12 
13 // -----------------------------------------------------------------------------
14 // ElemRestriction option
15 // -----------------------------------------------------------------------------
16 #[derive(Debug)]
17 pub enum ElemRestrictionOpt<'a> {
18     Some(&'a ElemRestriction<'a>),
19     None,
20 }
21 /// Construct a ElemRestrictionOpt reference from a ElemRestriction reference
22 impl<'a> From<&'a ElemRestriction<'_>> for ElemRestrictionOpt<'a> {
23     fn from(rstr: &'a ElemRestriction) -> Self {
24         debug_assert!(rstr.ptr != unsafe { bind_ceed::CEED_ELEMRESTRICTION_NONE });
25         Self::Some(rstr)
26     }
27 }
28 impl<'a> ElemRestrictionOpt<'a> {
29     /// Transform a Rust libCEED ElemRestrictionOpt into C libCEED
30     /// CeedElemRestriction
31     pub(crate) fn to_raw(self) -> bind_ceed::CeedElemRestriction {
32         match self {
33             Self::Some(rstr) => rstr.ptr,
34             Self::None => unsafe { bind_ceed::CEED_ELEMRESTRICTION_NONE },
35         }
36     }
37 
38     /// Check if an ElemRestrictionOpt is Some
39     ///
40     /// ```
41     /// # use libceed::prelude::*;
42     /// # fn main() -> libceed::Result<()> {
43     /// # let ceed = libceed::Ceed::default_init();
44     /// let nelem = 3;
45     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
46     /// for i in 0..nelem {
47     ///     ind[2 * i + 0] = i as i32;
48     ///     ind[2 * i + 1] = (i + 1) as i32;
49     /// }
50     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
51     /// let r_opt = ElemRestrictionOpt::from(&r);
52     /// assert!(r_opt.is_some(), "Incorrect ElemRestrictionOpt");
53     ///
54     /// let r_opt = ElemRestrictionOpt::None;
55     /// assert!(!r_opt.is_some(), "Incorrect ElemRestrictionOpt");
56     /// # Ok(())
57     /// # }
58     /// ```
59     pub fn is_some(&self) -> bool {
60         match self {
61             Self::Some(_) => true,
62             Self::None => false,
63         }
64     }
65 
66     /// Check if an ElemRestrictionOpt is None
67     ///
68     /// ```
69     /// # use libceed::prelude::*;
70     /// # fn main() -> libceed::Result<()> {
71     /// # let ceed = libceed::Ceed::default_init();
72     /// let nelem = 3;
73     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
74     /// for i in 0..nelem {
75     ///     ind[2 * i + 0] = i as i32;
76     ///     ind[2 * i + 1] = (i + 1) as i32;
77     /// }
78     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
79     /// let r_opt = ElemRestrictionOpt::from(&r);
80     /// assert!(!r_opt.is_none(), "Incorrect ElemRestrictionOpt");
81     ///
82     /// let r_opt = ElemRestrictionOpt::None;
83     /// assert!(r_opt.is_none(), "Incorrect ElemRestrictionOpt");
84     /// # Ok(())
85     /// # }
86     /// ```
87     pub fn is_none(&self) -> bool {
88         match self {
89             Self::Some(_) => false,
90             Self::None => true,
91         }
92     }
93 }
94 
95 // -----------------------------------------------------------------------------
96 // ElemRestriction context wrapper
97 // -----------------------------------------------------------------------------
98 #[derive(Debug)]
99 pub struct ElemRestriction<'a> {
100     pub(crate) ptr: bind_ceed::CeedElemRestriction,
101     _lifeline: PhantomData<&'a ()>,
102 }
103 
104 // -----------------------------------------------------------------------------
105 // Destructor
106 // -----------------------------------------------------------------------------
107 impl<'a> Drop for ElemRestriction<'a> {
108     fn drop(&mut self) {
109         unsafe {
110             if self.ptr != bind_ceed::CEED_ELEMRESTRICTION_NONE {
111                 bind_ceed::CeedElemRestrictionDestroy(&mut self.ptr);
112             }
113         }
114     }
115 }
116 
117 // -----------------------------------------------------------------------------
118 // Display
119 // -----------------------------------------------------------------------------
120 impl<'a> fmt::Display for ElemRestriction<'a> {
121     /// View an ElemRestriction
122     ///
123     /// ```
124     /// # use libceed::prelude::*;
125     /// # fn main() -> libceed::Result<()> {
126     /// # let ceed = libceed::Ceed::default_init();
127     /// let nelem = 3;
128     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
129     /// for i in 0..nelem {
130     ///     ind[2 * i + 0] = i as i32;
131     ///     ind[2 * i + 1] = (i + 1) as i32;
132     /// }
133     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
134     /// println!("{}", r);
135     /// # Ok(())
136     /// # }
137     /// ```
138     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
139         let mut ptr = std::ptr::null_mut();
140         let mut sizeloc = crate::MAX_BUFFER_LENGTH;
141         let cstring = unsafe {
142             let file = bind_ceed::open_memstream(&mut ptr, &mut sizeloc);
143             bind_ceed::CeedElemRestrictionView(self.ptr, file);
144             bind_ceed::fclose(file);
145             CString::from_raw(ptr)
146         };
147         cstring.to_string_lossy().fmt(f)
148     }
149 }
150 
151 // -----------------------------------------------------------------------------
152 // Implementations
153 // -----------------------------------------------------------------------------
154 impl<'a> ElemRestriction<'a> {
155     // Constructors
156     pub fn create(
157         ceed: &crate::Ceed,
158         nelem: usize,
159         elemsize: usize,
160         ncomp: usize,
161         compstride: usize,
162         lsize: usize,
163         mtype: crate::MemType,
164         offsets: &[i32],
165     ) -> crate::Result<Self> {
166         let mut ptr = std::ptr::null_mut();
167         let (nelem, elemsize, ncomp, compstride, lsize, mtype) = (
168             i32::try_from(nelem).unwrap(),
169             i32::try_from(elemsize).unwrap(),
170             i32::try_from(ncomp).unwrap(),
171             i32::try_from(compstride).unwrap(),
172             isize::try_from(lsize).unwrap(),
173             mtype as bind_ceed::CeedMemType,
174         );
175         let ierr = unsafe {
176             bind_ceed::CeedElemRestrictionCreate(
177                 ceed.ptr,
178                 nelem,
179                 elemsize,
180                 ncomp,
181                 compstride,
182                 lsize,
183                 mtype,
184                 crate::CopyMode::CopyValues as bind_ceed::CeedCopyMode,
185                 offsets.as_ptr(),
186                 &mut ptr,
187             )
188         };
189         ceed.check_error(ierr)?;
190         Ok(Self {
191             ptr,
192             _lifeline: PhantomData,
193         })
194     }
195 
196     pub(crate) fn from_raw(ptr: bind_ceed::CeedElemRestriction) -> crate::Result<Self> {
197         Ok(Self {
198             ptr,
199             _lifeline: PhantomData,
200         })
201     }
202 
203     pub fn create_oriented(
204         ceed: &crate::Ceed,
205         nelem: usize,
206         elemsize: usize,
207         ncomp: usize,
208         compstride: usize,
209         lsize: usize,
210         mtype: crate::MemType,
211         offsets: &[i32],
212         orients: &[bool],
213     ) -> crate::Result<Self> {
214         let mut ptr = std::ptr::null_mut();
215         let (nelem, elemsize, ncomp, compstride, lsize, mtype) = (
216             i32::try_from(nelem).unwrap(),
217             i32::try_from(elemsize).unwrap(),
218             i32::try_from(ncomp).unwrap(),
219             i32::try_from(compstride).unwrap(),
220             isize::try_from(lsize).unwrap(),
221             mtype as bind_ceed::CeedMemType,
222         );
223         let ierr = unsafe {
224             bind_ceed::CeedElemRestrictionCreateOriented(
225                 ceed.ptr,
226                 nelem,
227                 elemsize,
228                 ncomp,
229                 compstride,
230                 lsize,
231                 mtype,
232                 crate::CopyMode::CopyValues as bind_ceed::CeedCopyMode,
233                 offsets.as_ptr(),
234                 orients.as_ptr(),
235                 &mut ptr,
236             )
237         };
238         ceed.check_error(ierr)?;
239         Ok(Self {
240             ptr,
241             _lifeline: PhantomData,
242         })
243     }
244 
245     pub fn create_curl_oriented(
246         ceed: &crate::Ceed,
247         nelem: usize,
248         elemsize: usize,
249         ncomp: usize,
250         compstride: usize,
251         lsize: usize,
252         mtype: crate::MemType,
253         offsets: &[i32],
254         curlorients: &[i8],
255     ) -> crate::Result<Self> {
256         let mut ptr = std::ptr::null_mut();
257         let (nelem, elemsize, ncomp, compstride, lsize, mtype) = (
258             i32::try_from(nelem).unwrap(),
259             i32::try_from(elemsize).unwrap(),
260             i32::try_from(ncomp).unwrap(),
261             i32::try_from(compstride).unwrap(),
262             isize::try_from(lsize).unwrap(),
263             mtype as bind_ceed::CeedMemType,
264         );
265         let ierr = unsafe {
266             bind_ceed::CeedElemRestrictionCreateCurlOriented(
267                 ceed.ptr,
268                 nelem,
269                 elemsize,
270                 ncomp,
271                 compstride,
272                 lsize,
273                 mtype,
274                 crate::CopyMode::CopyValues as bind_ceed::CeedCopyMode,
275                 offsets.as_ptr(),
276                 curlorients.as_ptr(),
277                 &mut ptr,
278             )
279         };
280         ceed.check_error(ierr)?;
281         Ok(Self {
282             ptr,
283             _lifeline: PhantomData,
284         })
285     }
286 
287     pub fn create_strided(
288         ceed: &crate::Ceed,
289         nelem: usize,
290         elemsize: usize,
291         ncomp: usize,
292         lsize: usize,
293         strides: [i32; 3],
294     ) -> crate::Result<Self> {
295         let mut ptr = std::ptr::null_mut();
296         let (nelem, elemsize, ncomp, lsize) = (
297             i32::try_from(nelem).unwrap(),
298             i32::try_from(elemsize).unwrap(),
299             i32::try_from(ncomp).unwrap(),
300             isize::try_from(lsize).unwrap(),
301         );
302         let ierr = unsafe {
303             bind_ceed::CeedElemRestrictionCreateStrided(
304                 ceed.ptr,
305                 nelem,
306                 elemsize,
307                 ncomp,
308                 lsize,
309                 strides.as_ptr(),
310                 &mut ptr,
311             )
312         };
313         ceed.check_error(ierr)?;
314         Ok(Self {
315             ptr,
316             _lifeline: PhantomData,
317         })
318     }
319 
320     // Error handling
321     #[doc(hidden)]
322     fn check_error(&self, ierr: i32) -> crate::Result<i32> {
323         let mut ptr = std::ptr::null_mut();
324         unsafe {
325             bind_ceed::CeedElemRestrictionGetCeed(self.ptr, &mut ptr);
326         }
327         crate::check_error(ptr, ierr)
328     }
329 
330     /// Create an Lvector for an ElemRestriction
331     ///
332     /// ```
333     /// # use libceed::prelude::*;
334     /// # fn main() -> libceed::Result<()> {
335     /// # let ceed = libceed::Ceed::default_init();
336     /// let nelem = 3;
337     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
338     /// for i in 0..nelem {
339     ///     ind[2 * i + 0] = i as i32;
340     ///     ind[2 * i + 1] = (i + 1) as i32;
341     /// }
342     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
343     ///
344     /// let lvector = r.create_lvector()?;
345     ///
346     /// assert_eq!(lvector.length(), nelem + 1, "Incorrect Lvector size");
347     /// # Ok(())
348     /// # }
349     /// ```
350     pub fn create_lvector<'b>(&self) -> crate::Result<Vector<'b>> {
351         let mut ptr_lvector = std::ptr::null_mut();
352         let null = std::ptr::null_mut() as *mut _;
353         let ierr =
354             unsafe { bind_ceed::CeedElemRestrictionCreateVector(self.ptr, &mut ptr_lvector, null) };
355         self.check_error(ierr)?;
356         Vector::from_raw(ptr_lvector)
357     }
358 
359     /// Create an Evector for an ElemRestriction
360     ///
361     /// ```
362     /// # use libceed::prelude::*;
363     /// # fn main() -> libceed::Result<()> {
364     /// # let ceed = libceed::Ceed::default_init();
365     /// let nelem = 3;
366     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
367     /// for i in 0..nelem {
368     ///     ind[2 * i + 0] = i as i32;
369     ///     ind[2 * i + 1] = (i + 1) as i32;
370     /// }
371     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
372     ///
373     /// let evector = r.create_evector()?;
374     ///
375     /// assert_eq!(evector.length(), nelem * 2, "Incorrect Evector size");
376     /// # Ok(())
377     /// # }
378     /// ```
379     pub fn create_evector<'b>(&self) -> crate::Result<Vector<'b>> {
380         let mut ptr_evector = std::ptr::null_mut();
381         let null = std::ptr::null_mut() as *mut _;
382         let ierr =
383             unsafe { bind_ceed::CeedElemRestrictionCreateVector(self.ptr, null, &mut ptr_evector) };
384         self.check_error(ierr)?;
385         Vector::from_raw(ptr_evector)
386     }
387 
388     /// Create Vectors for an ElemRestriction
389     ///
390     /// ```
391     /// # use libceed::prelude::*;
392     /// # fn main() -> libceed::Result<()> {
393     /// # let ceed = libceed::Ceed::default_init();
394     /// let nelem = 3;
395     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
396     /// for i in 0..nelem {
397     ///     ind[2 * i + 0] = i as i32;
398     ///     ind[2 * i + 1] = (i + 1) as i32;
399     /// }
400     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
401     ///
402     /// let (lvector, evector) = r.create_vectors()?;
403     ///
404     /// assert_eq!(lvector.length(), nelem + 1, "Incorrect Lvector size");
405     /// assert_eq!(evector.length(), nelem * 2, "Incorrect Evector size");
406     /// # Ok(())
407     /// # }
408     /// ```
409     pub fn create_vectors<'b, 'c>(&self) -> crate::Result<(Vector<'b>, Vector<'c>)> {
410         let mut ptr_lvector = std::ptr::null_mut();
411         let mut ptr_evector = std::ptr::null_mut();
412         let ierr = unsafe {
413             bind_ceed::CeedElemRestrictionCreateVector(self.ptr, &mut ptr_lvector, &mut ptr_evector)
414         };
415         self.check_error(ierr)?;
416         let lvector = Vector::from_raw(ptr_lvector)?;
417         let evector = Vector::from_raw(ptr_evector)?;
418         Ok((lvector, evector))
419     }
420 
421     /// Restrict an Lvector to an Evector or apply its transpose
422     ///
423     /// # arguments
424     ///
425     /// * `tmode` - Apply restriction or transpose
426     /// * `u`     - Input vector (of size `lsize` when `TransposeMode::NoTranspose`)
427     /// * `ru`    - Output vector (of shape `[nelem * elemsize]` when
428     ///               `TransposeMode::NoTranspose`). Ordering of the Evector is
429     ///               decided by the backend.
430     ///
431     /// ```
432     /// # use libceed::prelude::*;
433     /// # fn main() -> libceed::Result<()> {
434     /// # let ceed = libceed::Ceed::default_init();
435     /// let nelem = 3;
436     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
437     /// for i in 0..nelem {
438     ///     ind[2 * i + 0] = i as i32;
439     ///     ind[2 * i + 1] = (i + 1) as i32;
440     /// }
441     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
442     ///
443     /// let x = ceed.vector_from_slice(&[0., 1., 2., 3.])?;
444     /// let mut y = ceed.vector(nelem * 2)?;
445     /// y.set_value(0.0);
446     ///
447     /// r.apply(TransposeMode::NoTranspose, &x, &mut y)?;
448     ///
449     /// for (i, y) in y.view()?.iter().enumerate() {
450     ///     assert_eq!(
451     ///         *y,
452     ///         ((i + 1) / 2) as Scalar,
453     ///         "Incorrect value in restricted vector"
454     ///     );
455     /// }
456     /// # Ok(())
457     /// # }
458     /// ```
459     pub fn apply(&self, tmode: TransposeMode, u: &Vector, ru: &mut Vector) -> crate::Result<i32> {
460         let tmode = tmode as bind_ceed::CeedTransposeMode;
461         let ierr = unsafe {
462             bind_ceed::CeedElemRestrictionApply(
463                 self.ptr,
464                 tmode,
465                 u.ptr,
466                 ru.ptr,
467                 bind_ceed::CEED_REQUEST_IMMEDIATE,
468             )
469         };
470         self.check_error(ierr)
471     }
472 
473     /// Returns the Lvector component stride
474     ///
475     /// ```
476     /// # use libceed::prelude::*;
477     /// # fn main() -> libceed::Result<()> {
478     /// # let ceed = libceed::Ceed::default_init();
479     /// let nelem = 3;
480     /// let compstride = 1;
481     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
482     /// for i in 0..nelem {
483     ///     ind[2 * i + 0] = i as i32;
484     ///     ind[2 * i + 1] = (i + 1) as i32;
485     /// }
486     /// let r = ceed.elem_restriction(nelem, 2, 1, compstride, nelem + 1, MemType::Host, &ind)?;
487     ///
488     /// let c = r.comp_stride();
489     /// assert_eq!(c, compstride, "Incorrect component stride");
490     /// # Ok(())
491     /// # }
492     /// ```
493     pub fn comp_stride(&self) -> usize {
494         let mut compstride = 0;
495         unsafe { bind_ceed::CeedElemRestrictionGetCompStride(self.ptr, &mut compstride) };
496         usize::try_from(compstride).unwrap()
497     }
498 
499     /// Returns the total number of elements in the range of a ElemRestriction
500     ///
501     /// ```
502     /// # use libceed::prelude::*;
503     /// # fn main() -> libceed::Result<()> {
504     /// # let ceed = libceed::Ceed::default_init();
505     /// let nelem = 3;
506     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
507     /// for i in 0..nelem {
508     ///     ind[2 * i + 0] = i as i32;
509     ///     ind[2 * i + 1] = (i + 1) as i32;
510     /// }
511     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
512     ///
513     /// let n = r.num_elements();
514     /// assert_eq!(n, nelem, "Incorrect number of elements");
515     /// # Ok(())
516     /// # }
517     /// ```
518     pub fn num_elements(&self) -> usize {
519         let mut numelem = 0;
520         unsafe { bind_ceed::CeedElemRestrictionGetNumElements(self.ptr, &mut numelem) };
521         usize::try_from(numelem).unwrap()
522     }
523 
524     /// Returns the size of elements in the ElemRestriction
525     ///
526     /// ```
527     /// # use libceed::prelude::*;
528     /// # fn main() -> libceed::Result<()> {
529     /// # let ceed = libceed::Ceed::default_init();
530     /// let nelem = 3;
531     /// let elem_size = 2;
532     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
533     /// for i in 0..nelem {
534     ///     ind[2 * i + 0] = i as i32;
535     ///     ind[2 * i + 1] = (i + 1) as i32;
536     /// }
537     /// let r = ceed.elem_restriction(nelem, elem_size, 1, 1, nelem + 1, MemType::Host, &ind)?;
538     ///
539     /// let e = r.elem_size();
540     /// assert_eq!(e, elem_size, "Incorrect element size");
541     /// # Ok(())
542     /// # }
543     /// ```
544     pub fn elem_size(&self) -> usize {
545         let mut elemsize = 0;
546         unsafe { bind_ceed::CeedElemRestrictionGetElementSize(self.ptr, &mut elemsize) };
547         usize::try_from(elemsize).unwrap()
548     }
549 
550     /// Returns the size of the Lvector for an ElemRestriction
551     ///
552     /// ```
553     /// # use libceed::prelude::*;
554     /// # fn main() -> libceed::Result<()> {
555     /// # let ceed = libceed::Ceed::default_init();
556     /// let nelem = 3;
557     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
558     /// for i in 0..nelem {
559     ///     ind[2 * i + 0] = i as i32;
560     ///     ind[2 * i + 1] = (i + 1) as i32;
561     /// }
562     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
563     ///
564     /// let lsize = r.lvector_size();
565     /// assert_eq!(lsize, nelem + 1);
566     /// # Ok(())
567     /// # }
568     /// ```
569     pub fn lvector_size(&self) -> usize {
570         let mut lsize = 0;
571         unsafe { bind_ceed::CeedElemRestrictionGetLVectorSize(self.ptr, &mut lsize) };
572         usize::try_from(lsize).unwrap()
573     }
574 
575     /// Returns the number of components in the elements of an ElemRestriction
576     ///
577     /// ```
578     /// # use libceed::prelude::*;
579     /// # fn main() -> libceed::Result<()> {
580     /// # let ceed = libceed::Ceed::default_init();
581     /// let nelem = 3;
582     /// let ncomp = 42;
583     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
584     /// for i in 0..nelem {
585     ///     ind[2 * i + 0] = i as i32;
586     ///     ind[2 * i + 1] = (i + 1) as i32;
587     /// }
588     /// let r = ceed.elem_restriction(nelem, 2, 42, 1, ncomp * (nelem + 1), MemType::Host, &ind)?;
589     ///
590     /// let n = r.num_components();
591     /// assert_eq!(n, ncomp, "Incorrect number of components");
592     /// # Ok(())
593     /// # }
594     /// ```
595     pub fn num_components(&self) -> usize {
596         let mut ncomp = 0;
597         unsafe { bind_ceed::CeedElemRestrictionGetNumComponents(self.ptr, &mut ncomp) };
598         usize::try_from(ncomp).unwrap()
599     }
600 
601     /// Returns the multiplicity of nodes in an ElemRestriction
602     ///
603     /// ```
604     /// # use libceed::prelude::*;
605     /// # fn main() -> libceed::Result<()> {
606     /// # let ceed = libceed::Ceed::default_init();
607     /// let nelem = 3;
608     /// let mut ind: Vec<i32> = vec![0; 2 * nelem];
609     /// for i in 0..nelem {
610     ///     ind[2 * i + 0] = i as i32;
611     ///     ind[2 * i + 1] = (i + 1) as i32;
612     /// }
613     /// let r = ceed.elem_restriction(nelem, 2, 1, 1, nelem + 1, MemType::Host, &ind)?;
614     ///
615     /// let mut mult = ceed.vector(nelem + 1)?;
616     /// mult.set_value(0.0);
617     ///
618     /// r.multiplicity(&mut mult)?;
619     ///
620     /// for (i, m) in mult.view()?.iter().enumerate() {
621     ///     assert_eq!(
622     ///         *m,
623     ///         if (i == 0 || i == nelem) { 1. } else { 2. },
624     ///         "Incorrect multiplicity value"
625     ///     );
626     /// }
627     /// # Ok(())
628     /// # }
629     /// ```
630     pub fn multiplicity(&self, mult: &mut Vector) -> crate::Result<i32> {
631         let ierr = unsafe { bind_ceed::CeedElemRestrictionGetMultiplicity(self.ptr, mult.ptr) };
632         self.check_error(ierr)
633     }
634 }
635 
636 // -----------------------------------------------------------------------------
637