star-line

Structure for accelerating line importance sampling
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sln_tree.c (19788B)


      1 /* Copyright (C) 2022, 2026 |Méso|Star> (contact@meso-star.com)
      2  * Copyright (C) 2026 Université de Lorraine
      3  * Copyright (C) 2022 Centre National de la Recherche Scientifique
      4  * Copyright (C) 2022 Université Paul Sabatier
      5  *
      6  * This program is free software: you can redistribute it and/or modify
      7  * it under the terms of the GNU General Public License as published by
      8  * the Free Software Foundation, either version 3 of the License, or
      9  * (at your option) any later version.
     10  *
     11  * This program is distributed in the hope that it will be useful,
     12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
     14  * GNU General Public License for more details.
     15  *
     16  * You should have received a copy of the GNU General Public License
     17  * along with this program. If not, see <http://www.gnu.org/licenses/>. */
     18 
     19 #include "sln.h"
     20 #include "sln_device_c.h"
     21 #include "sln_line.h"
     22 #include "sln_tree_c.h"
     23 
     24 #include <star/shtr.h>
     25 
     26 #include <rsys/algorithm.h>
     27 #include <rsys/cstr.h>
     28 #include <rsys/math.h>
     29 
     30 struct stream {
     31   const char* name;
     32   FILE* fp;
     33   int intern_fp; /* Define if the stream was internally opened */
     34 };
     35 static const struct stream STREAM_NULL = {NULL, NULL, 0};
     36 
     37 /*******************************************************************************
     38  * Helper functions
     39  ******************************************************************************/
     40 /* Check that the sum of the molecular concentrations is equal to 1 */
     41 static res_T
     42 check_molecule_concentration
     43   (struct sln_device* sln,
     44    const char* caller,
     45    const struct sln_tree_create_args* args)
     46 {
     47   int i = 0;
     48   double sum = 0;
     49   ASSERT(sln && caller && args);
     50 
     51   FOR_EACH(i, 0, SHTR_MAX_MOLECULE_COUNT) {
     52     if(i == SHTR_MOLECULE_ID_NULL) continue;
     53     sum += args->molecules[i].concentration;
     54   }
     55 
     56   /* The sum of molecular concentrations must be less than or equal to 1. It may
     57    * be less than 1 if the remaining part of the mixture is (implicitly) defined
     58    * as a radiatively inactive gas */
     59   if(sum > 1 && sum-1 > 1e-6) {
     60     ERROR(sln,
     61       "%s: the sum of molecule concentrations is greater than 1: %g\n",
     62       caller, sum);
     63     return RES_BAD_ARG;
     64   }
     65 
     66   return RES_OK;
     67 }
     68 
     69 /* Verify that the isotope abundance are valids */
     70 static res_T
     71 check_molecule_isotope_abundances
     72   (struct sln_device* sln,
     73    const char* caller,
     74    const struct sln_molecule* molecule)
     75 {
     76   int i = 0;
     77   double sum = 0;
     78   ASSERT(sln && caller && molecule);
     79 
     80   /* The isotopic abundances are the default ones. Nothing to do */
     81   if(!molecule->non_default_isotope_abundances) return RES_OK;
     82 
     83   /* The isotopic abundances are not the default ones.
     84    * Verify that they are valid ... */
     85   FOR_EACH(i, 0, SLN_MAX_ISOTOPES_COUNT) {
     86     if(molecule->isotopes[i].abundance < 0) {
     87       const int isotope_id = i + 1; /* isotope id in [1, 10] */
     88       ERROR(sln, "%s: invalid abundance of isotopie %d of %s: %g.\n",
     89         caller, isotope_id, shtr_molecule_cstr(i),
     90         molecule->isotopes[i].abundance);
     91       return RES_BAD_ARG;
     92     }
     93 
     94     sum += molecule->isotopes[i].abundance;
     95   }
     96 
     97   /* ... and that their sum equals 1 */
     98   if(!eq_eps(sum, 1, 1e-6)) {
     99     ERROR(sln, "%s: the %s isotope abundances does not sum to 1: %g.\n",
    100       caller, shtr_molecule_cstr(i), sum);
    101     return RES_BAD_ARG;
    102   }
    103 
    104   return RES_OK;
    105 }
    106 
    107 static res_T
    108 check_molecules
    109   (struct sln_device* sln,
    110    const char* caller,
    111    const struct sln_tree_create_args* args)
    112 {
    113   char molecule_ok[SHTR_MAX_MOLECULE_COUNT] = {0};
    114 
    115   double concentrations_sum = 0;
    116   size_t iline = 0;
    117   size_t nlines = 0;
    118   res_T res = RES_OK;
    119   ASSERT(args->lines);
    120 
    121   res = check_molecule_concentration(sln, caller, args);
    122   if(res != RES_OK) return res;
    123 
    124   /* Iterate over the lines to define which molecules has to be checked, i.e.,
    125    * the ones used in the mixture */
    126   SHTR(line_list_get_size(args->lines, &nlines));
    127   FOR_EACH(iline, 0, nlines) {
    128     struct shtr_line line = SHTR_LINE_NULL;
    129     const struct sln_molecule* molecule = NULL;
    130 
    131     SHTR(line_list_at(args->lines, iline, &line));
    132 
    133     /* This molecule was already checked */
    134     if(molecule_ok[line.molecule_id]) continue;
    135 
    136     molecule = args->molecules + line.molecule_id;
    137 
    138     if(molecule->concentration == 0) {
    139       /* A molecular concentration of zero is allowed, but may be a user error,
    140        * as 0 is the default concentration in the tree creation arguments.
    141        * Therefore, warn the user about this value so that they can determine
    142        * whether or not it is an error on their part. */
    143       WARN(sln, "%s: the concentration of %s is zero\n.\n",
    144         caller, shtr_molecule_cstr(line.molecule_id));
    145 
    146     } else if(molecule->concentration < 0) {
    147       /* Concentration cannot be negative... */
    148       ERROR(sln, "%s: invalid %s concentration: %g.\n",
    149         FUNC_NAME, shtr_molecule_cstr(line.molecule_id),
    150         molecule->concentration);
    151       return RES_BAD_ARG;
    152     }
    153 
    154     concentrations_sum += molecule->concentration;
    155 
    156     if(molecule->cutoff <= 0) {
    157       /* ... cutoff either */
    158       ERROR(sln, "%s: invalid %s cutoff: %g.\n",
    159         caller, shtr_molecule_cstr(line.molecule_id), molecule->cutoff);
    160       return RES_BAD_ARG;
    161     }
    162 
    163     res = check_molecule_isotope_abundances(sln, caller, molecule);
    164     if(res != RES_OK) return res;
    165 
    166     molecule_ok[line.molecule_id] = 1;
    167   }
    168 
    169   /* The sum of molecular concentrations must be less than or equal to 1. It may
    170    * be less than 1 if the remaining part of the mixture is (implicitly) defined
    171    * as a radiatively inactive gas */
    172   if(concentrations_sum > 1 && (concentrations_sum - 1) > 1e-6) {
    173     ERROR(sln,
    174       "%s: the sum of molecule concentrations is greater than 1: %g\n",
    175       caller, concentrations_sum);
    176     return RES_BAD_ARG;
    177   }
    178 
    179   return RES_OK;
    180 }
    181 
    182 static res_T
    183 check_sln_tree_create_args
    184   (struct sln_device* sln,
    185    const char* caller,
    186    const struct sln_tree_create_args* args)
    187 {
    188   res_T res = RES_OK;
    189   ASSERT(sln && caller);
    190 
    191   if(!args) return RES_BAD_ARG;
    192 
    193   if(!args->metadata) {
    194     ERROR(sln, "%s: the metadata is missing.\n", caller);
    195     return RES_BAD_ARG;
    196   }
    197 
    198   if(!args->lines) {
    199     ERROR(sln, "%s: the list of lines is missing.\n", caller);
    200     return RES_BAD_ARG;
    201   }
    202 
    203   if(args->nvertices_hint == 0) {
    204     ERROR(sln,
    205       "%s: invalid hint on the number of vertices around the line center %lu.\n",
    206       caller, (unsigned long)args->nvertices_hint);
    207     return RES_BAD_ARG;
    208   }
    209 
    210   if(args->mesh_decimation_err < 0) {
    211     ERROR(sln, "%s: invalid decimation error %g.\n",
    212       caller, args->mesh_decimation_err);
    213     return RES_BAD_ARG;
    214   }
    215 
    216   if((unsigned)args->mesh_type >= SLN_MESH_TYPES_COUNT__) {
    217     ERROR(sln, "%s: invalid mesh type %d.\n", caller, args->mesh_type);
    218     return RES_BAD_ARG;
    219   }
    220 
    221   if((unsigned)args->line_profile >= SLN_LINE_PROFILES_COUNT__) {
    222     ERROR(sln, "%s: invalid line profile %d.\n", caller, args->line_profile);
    223     return RES_BAD_ARG;
    224   }
    225 
    226   res = check_molecules(sln, caller, args);
    227   if(res != RES_OK) return res;
    228 
    229   return RES_OK;
    230 }
    231 
    232 static res_T
    233 check_sln_tree_read_args
    234   (struct sln_device* sln,
    235    const char* caller,
    236    const struct sln_tree_read_args* args)
    237 {
    238   if(!args) return RES_BAD_ARG;
    239 
    240   if(!args->shtr) {
    241     ERROR(sln,
    242       "%s: the handle to the Star-HITRAN library is missing.\n", caller);
    243     return RES_BAD_ARG;
    244   }
    245 
    246   if(!args->file && !args->filename) {
    247     ERROR(sln,
    248       "%s: the source file is missing. No file name or stream is provided.\n",
    249       caller);
    250     return RES_BAD_ARG;
    251   }
    252 
    253   return RES_OK;
    254 }
    255 
    256 static res_T
    257 check_sln_tree_write_args
    258   (struct sln_device* sln,
    259    const char* caller,
    260    const struct sln_tree_write_args* args)
    261 {
    262   if(!args) return RES_BAD_ARG;
    263 
    264   if(!args->file && !args->filename) {
    265     ERROR(sln,
    266       "%s: the destination file is missing. "
    267       "No file name or stream is provided.\n",
    268       caller);
    269     return RES_BAD_ARG;
    270   }
    271 
    272   return RES_OK;
    273 }
    274 static INLINE void
    275 stream_release(struct stream* stream)
    276 {
    277   ASSERT(stream);
    278   if(stream->intern_fp && stream->fp) CHK(fclose(stream->fp) == 0);
    279 }
    280 
    281 static res_T
    282 stream_init
    283   (struct sln_device* sln,
    284    const char* caller,
    285    const char* name, /* NULL <=> default stream name */
    286    FILE* fp, /* NULL <=> open file "name" */
    287    const char* mode, /* mode in fopen */
    288    struct stream* stream)
    289 {
    290   res_T res = RES_OK;
    291 
    292   ASSERT(sln && caller && stream);
    293   ASSERT(fp || (name && mode));
    294 
    295   *stream = STREAM_NULL;
    296 
    297   if(fp) {
    298     stream->intern_fp = 0;
    299     stream->name = name ? name : "stream";
    300     stream->fp = fp;
    301 
    302   } else {
    303     stream->intern_fp = 1;
    304     stream->name = name;
    305     if(!(stream->fp = fopen(name, mode))) {
    306       ERROR(sln, "%s:%s: error opening file -- %s\n",
    307         caller, name, strerror(errno));
    308       res = RES_IO_ERR;
    309       goto error;
    310     }
    311   }
    312 
    313 exit:
    314   return res;
    315 error:
    316   if(stream->intern_fp && stream->fp) CHK(fclose(stream->fp) == 0);
    317   goto exit;
    318 }
    319 
    320 static res_T
    321 create_tree
    322   (struct sln_device* sln,
    323    const char* caller,
    324    struct sln_tree** out_tree)
    325 {
    326   struct sln_tree* tree = NULL;
    327   res_T res = RES_OK;
    328   ASSERT(sln && caller && out_tree);
    329 
    330   tree = MEM_CALLOC(sln->allocator, 1, sizeof(struct sln_tree));
    331   if(!tree) {
    332     ERROR(sln, "%s: could not allocate the tree data structure.\n",
    333       caller);
    334     res = RES_MEM_ERR;
    335     goto error;
    336   }
    337   ref_init(&tree->ref);
    338   SLN(device_ref_get(sln));
    339   tree->sln = sln;
    340   darray_node_init(sln->allocator, &tree->nodes);
    341   darray_vertex_init(sln->allocator, &tree->vertices);
    342 
    343 exit:
    344   *out_tree = tree;
    345   return res;
    346 error:
    347   if(tree) { SLN(tree_ref_put(tree)); tree = NULL; }
    348   goto exit;
    349 }
    350 
    351 static INLINE int
    352 cmp_nu_vtx(const void* key, const void* item)
    353 {
    354   const float nu = *((const float*)key);
    355   const struct sln_vertex* vtx = item;
    356   if(nu < vtx->wavenumber) return -1;
    357   if(nu > vtx->wavenumber) return +1;
    358   return 0;
    359 }
    360 
    361 static void
    362 release_tree(ref_T* ref)
    363 {
    364   struct sln_tree* tree = CONTAINER_OF(ref, struct sln_tree, ref);
    365   struct sln_device* sln = NULL;
    366   ASSERT(ref);
    367   sln = tree->sln;
    368   darray_node_release(&tree->nodes);
    369   darray_vertex_release(&tree->vertices);
    370   if(tree->args.lines) SHTR(line_list_ref_put(tree->args.lines));
    371   if(tree->args.metadata) SHTR(isotope_metadata_ref_put(tree->args.metadata));
    372   MEM_RM(sln->allocator, tree);
    373   SLN(device_ref_put(sln));
    374 }
    375 
    376 /*******************************************************************************
    377  * Exported symbols
    378  ******************************************************************************/
    379 res_T
    380 sln_tree_create
    381   (struct sln_device* device,
    382    const struct sln_tree_create_args* args,
    383    struct sln_tree** out_tree)
    384 {
    385   struct sln_tree* tree = NULL;
    386   res_T res = RES_OK;
    387 
    388   if(!device || !out_tree) { res = RES_BAD_ARG; goto error; }
    389   res = check_sln_tree_create_args(device, FUNC_NAME, args);
    390   if(res != RES_OK) goto error;
    391 
    392   res = create_tree(device, FUNC_NAME, &tree);
    393   if(res != RES_OK) goto error;
    394   SHTR(line_list_ref_get(args->lines));
    395   SHTR(isotope_metadata_ref_get(args->metadata));
    396   tree->args = *args;
    397 
    398   res = tree_build(tree);
    399   if(res != RES_OK) goto error;
    400 
    401 exit:
    402   if(out_tree) *out_tree = tree;
    403   return res;
    404 error:
    405   if(tree) { SLN(tree_ref_put(tree)); tree = NULL; }
    406   goto exit;
    407 }
    408 
    409 res_T
    410 sln_tree_read
    411   (struct sln_device* sln,
    412    const struct sln_tree_read_args* args,
    413    struct sln_tree** out_tree)
    414 {
    415   struct shtr_line_list_read_args rlines_args = SHTR_LINE_LIST_READ_ARGS_NULL;
    416   struct stream stream = STREAM_NULL;
    417   struct sln_tree* tree = NULL;
    418   size_t n = 0;
    419   int version = 0;
    420   res_T res = RES_OK;
    421 
    422   if(!sln || !out_tree) { res = RES_BAD_ARG; goto error; }
    423   res = check_sln_tree_read_args(sln, FUNC_NAME, args);
    424   if(res != RES_OK) goto error;
    425 
    426   res = create_tree(sln, FUNC_NAME, &tree);
    427   if(res != RES_OK) goto error;
    428 
    429   res = stream_init(sln, FUNC_NAME, args->filename, args->file, "r", &stream);
    430   if(res != RES_OK) goto error;
    431 
    432   #define READ(Var, Nb) {                                                      \
    433     if(fread((Var), sizeof(*(Var)), (Nb), stream.fp) != (Nb)) {                \
    434       if(feof(stream.fp)) {                                                    \
    435         res = RES_BAD_ARG;                                                     \
    436       } else if(ferror(stream.fp)) {                                           \
    437         res = RES_IO_ERR;                                                      \
    438       } else {                                                                 \
    439         res = RES_UNKNOWN_ERR;                                                 \
    440       }                                                                        \
    441       goto error;                                                              \
    442     }                                                                          \
    443   } (void)0
    444   READ(&version, 1);
    445   if(version != SLN_TREE_VERSION) {
    446     ERROR(sln,
    447       "%s: unexpected tree version %d. Expecting a tree in version %d.\n",
    448       FUNC_NAME, version, SLN_TREE_VERSION);
    449     res = RES_BAD_ARG;
    450     goto error;
    451   }
    452 
    453   READ(&n, 1);
    454   if((res = darray_node_resize(&tree->nodes, n)) != RES_OK) goto error;
    455   READ(darray_node_data_get(&tree->nodes), n);
    456 
    457   READ(&n, 1);
    458   if((res = darray_vertex_resize(&tree->vertices, n)) != RES_OK) goto error;
    459   READ(darray_vertex_data_get(&tree->vertices), n);
    460 
    461   READ(&tree->args.line_profile, 1);
    462   READ(&tree->args.molecules, 1);
    463   READ(&tree->args.pressure, 1);
    464   READ(&tree->args.temperature, 1);
    465   READ(&tree->args.nvertices_hint, 1);
    466   READ(&tree->args.mesh_decimation_err, 1);
    467   READ(&tree->args.mesh_type, 1);
    468   #undef READ
    469 
    470   res = shtr_isotope_metadata_create_from_stream
    471     (args->shtr, stream.fp, &tree->args.metadata);
    472   if(res != RES_OK) goto error;
    473 
    474   rlines_args.file = stream.fp;
    475   res = shtr_line_list_read(args->shtr, &rlines_args, &tree->args.lines);
    476   if(res != RES_OK) goto error;
    477 
    478 exit:
    479   stream_release(&stream);
    480   if(out_tree) *out_tree = tree;
    481   return res;
    482 error:
    483   if(tree) { SLN(tree_ref_put(tree)); tree = NULL; }
    484   if(sln) {
    485     ERROR(sln, "%s: error loading the tree structure -- %s.\n",
    486       FUNC_NAME, res_to_cstr(res));
    487   }
    488   goto exit;
    489 }
    490 
    491 res_T
    492 sln_tree_ref_get(struct sln_tree* tree)
    493 {
    494   if(!tree) return RES_BAD_ARG;
    495   ref_get(&tree->ref);
    496   return RES_OK;
    497 }
    498 
    499 res_T
    500 sln_tree_ref_put(struct sln_tree* tree)
    501 {
    502   if(!tree) return RES_BAD_ARG;
    503   ref_put(&tree->ref, release_tree);
    504   return RES_OK;
    505 }
    506 
    507 res_T
    508 sln_tree_get_desc(const struct sln_tree* tree, struct sln_tree_desc* desc)
    509 {
    510   if(!tree || !desc) return RES_BAD_ARG;
    511   desc->max_nlines_per_leaf = 1;
    512   desc->mesh_decimation_err = tree->args.mesh_decimation_err;
    513   desc->mesh_type = tree->args.mesh_type;
    514   desc->line_profile = tree->args.line_profile;
    515   desc->nnodes = darray_node_size_get(&tree->nodes);
    516   desc->nvertices = darray_vertex_size_get(&tree->vertices);
    517   return RES_OK;
    518 }
    519 
    520 const struct sln_node*
    521 sln_tree_get_root(const struct sln_tree* tree)
    522 {
    523   ASSERT(tree);
    524   if(darray_node_size_get(&tree->nodes)) {
    525     return darray_node_cdata_get(&tree->nodes);
    526   } else {
    527     return NULL;
    528   }
    529 }
    530 
    531 int
    532 sln_node_is_leaf(const struct sln_node* node)
    533 {
    534   ASSERT(node);
    535   return node->offset == 0;
    536 }
    537 
    538 const struct sln_node*
    539 sln_node_get_child(const struct sln_node* node, const unsigned ichild)
    540 {
    541   ASSERT(node && ichild <= 1);
    542   return node + node->offset + ichild;
    543 }
    544 
    545 size_t
    546 sln_node_get_lines_count(const struct sln_node* node)
    547 {
    548   ASSERT(node);
    549   return node->range[1] - node->range[0] + 1/*Both boundaries are inclusives*/;
    550 }
    551 
    552 res_T
    553 sln_node_get_line
    554   (const struct sln_tree* tree,
    555    const struct sln_node* node,
    556    const size_t iline,
    557    struct shtr_line* line)
    558 {
    559   if(!tree || !node || iline > sln_node_get_lines_count(node))
    560     return RES_BAD_ARG;
    561 
    562   return shtr_line_list_at
    563     (tree->args.lines, node->range[0] + iline, line);
    564 }
    565 
    566 res_T
    567 sln_node_get_mesh
    568   (const struct sln_tree* tree,
    569    const struct sln_node* node,
    570    struct sln_mesh* mesh)
    571 {
    572   if(!tree || !node || !mesh) return RES_BAD_ARG;
    573   mesh->vertices = darray_vertex_cdata_get(&tree->vertices) + node->ivertex;
    574   mesh->nvertices = node->nvertices;
    575   return RES_OK;
    576 }
    577 
    578 double
    579 sln_node_eval
    580   (const struct sln_tree* tree,
    581    const struct sln_node* node,
    582    const double nu)
    583 {
    584   double ka = 0;
    585   size_t iline;
    586   ASSERT(tree && node);
    587 
    588   FOR_EACH(iline, node->range[0], node->range[1]+1) {
    589     struct line line = LINE_NULL;
    590     res_T res = RES_OK;
    591 
    592     res = line_setup(tree, iline, &line);
    593     if(res != RES_OK) {
    594       WARN(tree->sln, "%s: could not setup the line %lu-- %s\n",
    595         FUNC_NAME, iline, res_to_cstr(res));
    596     }
    597 
    598     ka += line_value(tree, &line, nu);
    599   }
    600   return ka;
    601 }
    602 
    603 double
    604 sln_mesh_eval(const struct sln_mesh* mesh, const double wavenumber)
    605 {
    606   const struct sln_vertex* vtx0 = NULL;
    607   const struct sln_vertex* vtx1 = NULL;
    608   const float nu = (float)wavenumber;
    609   size_t n; /* #vertices */
    610   float u; /* Linear interpolation paraeter */
    611   ASSERT(mesh && mesh->nvertices);
    612 
    613   n = mesh->nvertices;
    614 
    615   /* Handle special cases */
    616   if(n == 1) return mesh->vertices[0].ka;
    617   if(nu <= mesh->vertices[0].wavenumber) return mesh->vertices[0].ka;
    618   if(nu >= mesh->vertices[n-1].wavenumber) return mesh->vertices[n-1].ka;
    619 
    620   /* Dichotomic search of the mesh vertex whose wavenumber is greater than or
    621    * equal to the submitted wavenumber 'nu' */
    622   vtx1 = search_lower_bound(&nu, mesh->vertices, n, sizeof(*vtx1), cmp_nu_vtx);
    623   vtx0 = vtx1 - 1;
    624   ASSERT(vtx1); /* A vertex is necessary found ...*/
    625   ASSERT(vtx1 > mesh->vertices); /* ... and it cannot be the first one */
    626   ASSERT(vtx0->wavenumber < nu && nu <= vtx1->wavenumber);
    627 
    628   /* Compute the linear interpolation parameter */
    629   u = (nu - vtx0->wavenumber) / (vtx1->wavenumber - vtx0->wavenumber);
    630   u = CLAMP(u, 0, 1); /* Handle numerical imprecisions */
    631 
    632   if(u == 0) return vtx0->ka;
    633   if(u == 1) return vtx1->ka;
    634   return u*(vtx1->ka - vtx0->ka) + vtx0->ka;
    635 }
    636 
    637 res_T
    638 sln_tree_write
    639   (const struct sln_tree* tree,
    640    const struct sln_tree_write_args* args)
    641 {
    642   struct shtr_line_list_write_args wlines_args = SHTR_LINE_LIST_WRITE_ARGS_NULL;
    643   struct stream stream = STREAM_NULL;
    644   size_t nnodes, nverts;
    645   res_T res = RES_OK;
    646 
    647   if(!tree) { res = RES_BAD_ARG; goto error; }
    648   res = check_sln_tree_write_args(tree->sln, FUNC_NAME, args);
    649   if(res != RES_OK) goto error;
    650 
    651   res = stream_init
    652     (tree->sln, FUNC_NAME, args->filename, args->file, "w", &stream);
    653   if(res != RES_OK) goto error;
    654 
    655   #define WRITE(Var, Nb) {                                                     \
    656     if(fwrite((Var), sizeof(*(Var)), (Nb), stream.fp) != (Nb)) {               \
    657       ERROR(tree->sln, "%s:%s: error writing the tree -- %s\n",                \
    658         FUNC_NAME, stream.name, strerror(errno));                              \
    659       res = RES_IO_ERR;                                                        \
    660       goto error;                                                              \
    661     }                                                                          \
    662   } (void)0
    663   WRITE(&SLN_TREE_VERSION, 1);
    664 
    665   nnodes = darray_node_size_get(&tree->nodes);
    666   WRITE(&nnodes, 1);
    667   WRITE(darray_node_cdata_get(&tree->nodes), nnodes);
    668 
    669   nverts = darray_vertex_size_get(&tree->vertices);
    670   WRITE(&nverts, 1);
    671   WRITE(darray_vertex_cdata_get(&tree->vertices), nverts);
    672 
    673   WRITE(&tree->args.line_profile, 1);
    674   WRITE(&tree->args.molecules, 1);
    675   WRITE(&tree->args.pressure, 1);
    676   WRITE(&tree->args.temperature, 1);
    677   WRITE(&tree->args.nvertices_hint, 1);
    678   WRITE(&tree->args.mesh_decimation_err, 1);
    679   WRITE(&tree->args.mesh_type, 1);
    680   #undef WRITE
    681 
    682   res = shtr_isotope_metadata_write(tree->args.metadata, stream.fp);
    683   if(res != RES_OK) goto error;
    684 
    685   wlines_args.file = stream.fp;
    686   res = shtr_line_list_write(tree->args.lines, &wlines_args);
    687   if(res != RES_OK) goto error;
    688 
    689 exit:
    690   stream_release(&stream);
    691   return res;
    692 error:
    693   goto exit;
    694 }