1 /* PSPP - a program for statistical analysis.
2 Copyright (C) 1997-9, 2000, 2006, 2007, 2009, 2010, 2011, 2013 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 #include "data/dataset.h"
26 #include "data/case.h"
27 #include "data/case-map.h"
28 #include "data/caseinit.h"
29 #include "data/casereader.h"
30 #include "data/casereader-provider.h"
31 #include "data/casereader-shim.h"
32 #include "data/casewriter.h"
33 #include "data/dictionary.h"
34 #include "data/file-handle-def.h"
35 #include "data/session.h"
36 #include "data/transformations.h"
37 #include "data/variable.h"
38 #include "libpspp/deque.h"
39 #include "libpspp/hash-functions.h"
40 #include "libpspp/hmap.h"
41 #include "libpspp/misc.h"
42 #include "libpspp/str.h"
43 #include "libpspp/taint.h"
44 #include "libpspp/i18n.h"
46 #include "gl/minmax.h"
47 #include "gl/xalloc.h"
50 /* A dataset is usually part of a session. Within a session its name must
51 unique. The name must either be a valid PSPP identifier or the empty
52 string. (It must be unique within the session even if it is the empty
53 string; that is, there may only be a single dataset within a session with
54 the empty string as its name.) */
55 struct session *session;
57 enum dataset_display display;
59 /* Cases are read from source,
60 their transformation variables are initialized,
61 pass through permanent_trns_chain (which transforms them into
62 the format described by permanent_dict),
64 pass through temporary_trns_chain (which transforms them into
65 the format described by dict),
66 and are finally passed to the procedure. */
67 struct casereader *source;
68 struct caseinit *caseinit;
69 struct trns_chain permanent_trns_chain;
70 struct dictionary *permanent_dict;
71 struct variable *order_var;
72 struct casewriter *sink;
73 struct trns_chain temporary_trns_chain;
75 struct dictionary *dict;
77 /* Stack of transformation chains for DO IF and LOOP and INPUT PROGRAM. */
78 struct trns_chain *stack;
80 size_t allocated_stack;
82 /* If true, cases are discarded instead of being written to
86 /* Time at which proc was last invoked. */
87 time_t last_proc_invocation;
89 /* Cases just before ("lagging") the current one. */
90 int n_lag; /* Number of cases to lag. */
91 struct deque lag; /* Deque of lagged cases. */
92 struct ccase **lag_cases; /* Lagged cases managed by deque. */
97 PROC_COMMITTED, /* No procedure in progress. */
98 PROC_OPEN, /* proc_open called, casereader still open. */
99 PROC_CLOSED /* casereader from proc_open destroyed,
100 but proc_commit not yet called. */
103 casenumber cases_written; /* Cases output so far. */
104 bool ok; /* Error status. */
105 struct casereader_shim *shim; /* Shim on proc_open() casereader. */
107 const struct dataset_callbacks *callbacks;
110 /* Uniquely distinguishes datasets. */
114 static void dataset_changed__ (struct dataset *);
115 static void dataset_transformations_changed__ (struct dataset *,
118 static void add_measurement_level_trns (struct dataset *, struct dictionary *);
119 static void cancel_measurement_level_trns (struct trns_chain *);
120 static void add_case_limit_trns (struct dataset *ds);
121 static void add_filter_trns (struct dataset *ds);
123 static void update_last_proc_invocation (struct dataset *ds);
126 dict_callback (struct dictionary *d UNUSED, void *ds_)
128 struct dataset *ds = ds_;
129 dataset_changed__ (ds);
133 dataset_create_finish__ (struct dataset *ds, struct session *session)
135 static unsigned int seqno;
137 dict_set_change_callback (ds->dict, dict_callback, ds);
138 proc_cancel_all_transformations (ds);
139 dataset_set_session (ds, session);
143 /* Creates a new dataset named NAME, adds it to SESSION, and returns it. If
144 SESSION already contains a dataset named NAME, it is deleted and replaced.
145 The dataset initially has an empty dictionary and no data source. */
147 dataset_create (struct session *session, const char *name)
149 struct dataset *ds = XMALLOC (struct dataset);
150 *ds = (struct dataset) {
151 .name = xstrdup (name),
152 .display = DATASET_FRONT,
153 .dict = dict_create (get_default_encoding ()),
154 .caseinit = caseinit_create (),
156 dataset_create_finish__ (ds, session);
161 /* Creates and returns a new dataset that has the same data and dictionary as
162 OLD named NAME, adds it to the same session as OLD, and returns the new
163 dataset. If SESSION already contains a dataset named NAME, it is deleted
166 OLD must not have any active transformations or temporary state and must
167 not be in the middle of a procedure.
169 Callbacks are not cloned. */
171 dataset_clone (struct dataset *old, const char *name)
175 assert (old->proc_state == PROC_COMMITTED);
176 assert (!old->permanent_trns_chain.n);
177 assert (old->permanent_dict == NULL);
178 assert (old->sink == NULL);
179 assert (!old->temporary);
180 assert (!old->temporary_trns_chain.n);
181 assert (!old->n_stack);
183 new = xzalloc (sizeof *new);
184 new->name = xstrdup (name);
185 new->display = DATASET_FRONT;
186 new->source = casereader_clone (old->source);
187 new->dict = dict_clone (old->dict);
188 new->caseinit = caseinit_clone (old->caseinit);
189 new->last_proc_invocation = old->last_proc_invocation;
192 dataset_create_finish__ (new, old->session);
199 dataset_destroy (struct dataset *ds)
203 dataset_set_session (ds, NULL);
205 dict_unref (ds->dict);
206 dict_unref (ds->permanent_dict);
207 caseinit_destroy (ds->caseinit);
208 trns_chain_uninit (&ds->permanent_trns_chain);
209 for (size_t i = 0; i < ds->n_stack; i++)
210 trns_chain_uninit (&ds->stack[i]);
212 dataset_transformations_changed__ (ds, false);
218 /* Discards the active dataset's dictionary, data, and transformations. */
220 dataset_clear (struct dataset *ds)
222 assert (ds->proc_state == PROC_COMMITTED);
224 dict_clear (ds->dict);
225 fh_set_default_handle (NULL);
229 casereader_destroy (ds->source);
232 proc_cancel_all_transformations (ds);
236 dataset_name (const struct dataset *ds)
242 dataset_set_name (struct dataset *ds, const char *name)
244 struct session *session = ds->session;
249 active = session_active_dataset (session) == ds;
251 session_set_active_dataset (session, NULL);
252 dataset_set_session (ds, NULL);
256 ds->name = xstrdup (name);
260 dataset_set_session (ds, session);
262 session_set_active_dataset (session, ds);
267 dataset_session (const struct dataset *ds)
273 dataset_set_session (struct dataset *ds, struct session *session)
275 if (session != ds->session)
277 if (ds->session != NULL)
278 session_remove_dataset (ds->session, ds);
280 session_add_dataset (session, ds);
284 /* Returns the dictionary within DS. This is always nonnull, although it
285 might not contain any variables. */
287 dataset_dict (const struct dataset *ds)
292 /* Replaces DS's dictionary by DICT, discarding any source and
295 dataset_set_dict (struct dataset *ds, struct dictionary *dict)
297 assert (ds->proc_state == PROC_COMMITTED);
298 assert (ds->dict != dict);
302 dict_unref (ds->dict);
304 dict_set_change_callback (ds->dict, dict_callback, ds);
307 /* Returns the casereader that will be read when a procedure is executed on
308 DS. This can be NULL if none has been set up yet. */
309 const struct casereader *
310 dataset_source (const struct dataset *ds)
315 /* Returns true if DS has a data source, false otherwise. */
317 dataset_has_source (const struct dataset *ds)
319 return dataset_source (ds) != NULL;
322 /* Replaces the active dataset's data by READER. READER's cases must have an
323 appropriate format for DS's dictionary. */
325 dataset_set_source (struct dataset *ds, struct casereader *reader)
327 casereader_destroy (ds->source);
330 caseinit_clear (ds->caseinit);
331 caseinit_mark_as_preinited (ds->caseinit, ds->dict);
333 return reader == NULL || !casereader_error (reader);
336 /* Returns the data source from DS and removes it from DS. Returns a null
337 pointer if DS has no data source. */
339 dataset_steal_source (struct dataset *ds)
341 struct casereader *reader = ds->source;
348 dataset_delete_vars (struct dataset *ds, struct variable **vars, size_t n)
350 assert (!proc_in_temporary_transformations (ds));
351 assert (!proc_has_transformations (ds));
352 assert (n < dict_get_n_vars (ds->dict));
354 caseinit_mark_for_init (ds->caseinit, ds->dict);
355 ds->source = caseinit_translate_casereader_to_init_vars (
356 ds->caseinit, dict_get_proto (ds->dict), ds->source);
357 caseinit_clear (ds->caseinit);
358 caseinit_mark_as_preinited (ds->caseinit, ds->dict);
360 struct case_map_stage *stage = case_map_stage_create (ds->dict);
361 dict_delete_vars (ds->dict, vars, n);
362 ds->source = case_map_create_input_translator (
363 case_map_stage_to_case_map (stage), ds->source);
364 caseinit_clear (ds->caseinit);
365 caseinit_mark_as_preinited (ds->caseinit, ds->dict);
369 dataset_reorder_vars (struct dataset *ds, struct variable **vars, size_t n)
371 assert (!proc_in_temporary_transformations (ds));
372 assert (!proc_has_transformations (ds));
373 assert (n <= dict_get_n_vars (ds->dict));
375 caseinit_mark_for_init (ds->caseinit, ds->dict);
376 ds->source = caseinit_translate_casereader_to_init_vars (
377 ds->caseinit, dict_get_proto (ds->dict), ds->source);
378 caseinit_clear (ds->caseinit);
379 caseinit_mark_as_preinited (ds->caseinit, ds->dict);
381 struct case_map_stage *stage = case_map_stage_create (ds->dict);
382 dict_reorder_vars (ds->dict, vars, n);
383 ds->source = case_map_create_input_translator (
384 case_map_stage_to_case_map (stage), ds->source);
385 caseinit_clear (ds->caseinit);
386 caseinit_mark_as_preinited (ds->caseinit, ds->dict);
389 /* Returns a number unique to DS. It can be used to distinguish one dataset
390 from any other within a given program run, even datasets that do not exist
393 dataset_seqno (const struct dataset *ds)
399 dataset_set_callbacks (struct dataset *ds,
400 const struct dataset_callbacks *callbacks,
403 ds->callbacks = callbacks;
404 ds->cb_data = cb_data;
408 dataset_get_display (const struct dataset *ds)
414 dataset_set_display (struct dataset *ds, enum dataset_display display)
416 ds->display = display;
419 /* Returns the last time the data was read. */
421 time_of_last_procedure (struct dataset *ds)
425 if (ds->last_proc_invocation == 0)
426 update_last_proc_invocation (ds);
427 return ds->last_proc_invocation;
430 /* Regular procedure. */
432 /* Executes any pending transformations, if necessary.
433 This is not identical to the EXECUTE command in that it won't
434 always read the source data. This can be important when the
435 source data is given inline within BEGIN DATA...END FILE. */
437 proc_execute (struct dataset *ds)
441 if ((!ds->temporary || !ds->temporary_trns_chain.n)
442 && !ds->permanent_trns_chain.n)
445 ds->discard_output = false;
446 dict_set_case_limit (ds->dict, 0);
447 dict_clear_vectors (ds->dict);
451 ok = casereader_destroy (proc_open (ds));
452 return proc_commit (ds) && ok;
455 static const struct casereader_class proc_casereader_class;
457 /* Opens dataset DS for reading cases with proc_read. If FILTER is true, then
458 cases filtered out with FILTER BY will not be included in the casereader
459 (which is usually desirable). If FILTER is false, all cases will be
460 included regardless of FILTER BY settings.
462 proc_commit must be called when done. */
464 proc_open_filtering (struct dataset *ds, bool filter)
466 struct casereader *reader;
468 assert (ds->n_stack == 0);
469 assert (ds->source != NULL);
470 assert (ds->proc_state == PROC_COMMITTED);
472 update_last_proc_invocation (ds);
474 caseinit_mark_for_init (ds->caseinit, ds->dict);
475 ds->source = caseinit_translate_casereader_to_init_vars (
476 ds->caseinit, dict_get_proto (ds->dict), ds->source);
478 /* Finish up the collection of transformations. */
479 add_case_limit_trns (ds);
481 add_filter_trns (ds);
482 if (!proc_in_temporary_transformations (ds))
483 add_measurement_level_trns (ds, ds->dict);
485 /* Make permanent_dict refer to the dictionary right before
486 data reaches the sink. */
487 if (ds->permanent_dict == NULL)
488 ds->permanent_dict = ds->dict;
491 if (!ds->discard_output)
493 struct dictionary *pd = dict_clone (ds->permanent_dict);
494 struct case_map_stage *stage = case_map_stage_create (pd);
495 dict_delete_scratch_vars (pd);
496 ds->sink = case_map_create_output_translator (
497 case_map_stage_to_case_map (stage),
498 autopaging_writer_create (dict_get_proto (pd)));
504 /* Allocate memory for lagged cases. */
505 ds->lag_cases = deque_init (&ds->lag, ds->n_lag, sizeof *ds->lag_cases);
507 ds->proc_state = PROC_OPEN;
508 ds->cases_written = 0;
511 /* FIXME: use taint in dataset in place of `ok'? */
512 /* FIXME: for trivial cases we can just return a clone of
515 /* Create casereader and insert a shim on top. The shim allows us to
516 arbitrarily extend the casereader's lifetime, by slurping the cases into
517 the shim's buffer in proc_commit(). That is especially useful when output
518 table_items are generated directly from the procedure casereader (e.g. by
519 the LIST procedure) when we are using an output driver that keeps a
520 reference to the output items passed to it (e.g. the GUI output driver in
522 reader = casereader_create_sequential (NULL, dict_get_proto (ds->dict),
524 &proc_casereader_class, ds);
525 ds->shim = casereader_shim_insert (reader);
529 /* Opens dataset DS for reading cases with proc_read.
530 proc_commit must be called when done. */
532 proc_open (struct dataset *ds)
534 return proc_open_filtering (ds, true);
537 /* Returns true if a procedure is in progress, that is, if
538 proc_open has been called but proc_commit has not. */
540 proc_is_open (const struct dataset *ds)
542 return ds->proc_state != PROC_COMMITTED;
545 /* "read" function for procedure casereader. */
546 static struct ccase *
547 proc_casereader_read (struct casereader *reader UNUSED, void *ds_)
549 struct dataset *ds = ds_;
550 enum trns_result retval = TRNS_DROP_CASE;
553 assert (ds->proc_state == PROC_OPEN);
554 for (; ; case_unref (c))
556 assert (retval == TRNS_DROP_CASE || retval == TRNS_ERROR);
557 if (retval == TRNS_ERROR)
562 /* Read a case from source. */
563 c = casereader_read (ds->source);
566 c = case_unshare_and_resize (c, dict_get_proto (ds->dict));
567 caseinit_restore_left_vars (ds->caseinit, c);
569 /* Execute permanent transformations. */
570 casenumber case_nr = ds->cases_written + 1;
571 retval = trns_chain_execute (&ds->permanent_trns_chain, case_nr, &c);
572 caseinit_save_left_vars (ds->caseinit, c);
573 if (retval != TRNS_CONTINUE)
576 /* Write case to collection of lagged cases. */
579 while (deque_count (&ds->lag) >= ds->n_lag)
580 case_unref (ds->lag_cases[deque_pop_back (&ds->lag)]);
581 ds->lag_cases[deque_push_front (&ds->lag)] = case_ref (c);
584 /* Write case to replacement dataset. */
586 if (ds->sink != NULL)
589 *case_num_rw (c, ds->order_var) = case_nr;
590 casewriter_write (ds->sink, case_ref (c));
593 /* Execute temporary transformations. */
594 if (ds->temporary_trns_chain.n)
596 retval = trns_chain_execute (&ds->temporary_trns_chain,
597 ds->cases_written, &c);
598 if (retval != TRNS_CONTINUE)
606 /* "destroy" function for procedure casereader. */
608 proc_casereader_destroy (struct casereader *reader, void *ds_)
610 struct dataset *ds = ds_;
613 /* We are always the subreader for a casereader_buffer, so if we're being
614 destroyed then it's because the casereader_buffer has read all the cases
615 that it ever will. */
618 /* Make sure transformations happen for every input case, in
619 case they have side effects, and ensure that the replacement
620 active dataset gets all the cases it should. */
621 while ((c = casereader_read (reader)) != NULL)
624 ds->proc_state = PROC_CLOSED;
625 ds->ok = casereader_destroy (ds->source) && ds->ok;
627 dataset_set_source (ds, NULL);
630 /* Must return false if the source casereader, a transformation,
631 or the sink casewriter signaled an error. (If a temporary
632 transformation signals an error, then the return value is
633 false, but the replacement active dataset may still be
636 proc_commit (struct dataset *ds)
638 if (ds->shim != NULL)
639 casereader_shim_slurp (ds->shim);
641 assert (ds->proc_state == PROC_CLOSED);
642 ds->proc_state = PROC_COMMITTED;
644 dataset_changed__ (ds);
646 /* Free memory for lagged cases. */
647 while (!deque_is_empty (&ds->lag))
648 case_unref (ds->lag_cases[deque_pop_back (&ds->lag)]);
649 free (ds->lag_cases);
651 /* Dictionary from before TEMPORARY becomes permanent. */
652 proc_cancel_temporary_transformations (ds);
653 bool ok = proc_cancel_all_transformations (ds) && ds->ok;
655 if (!ds->discard_output)
657 dict_delete_scratch_vars (ds->dict);
659 /* Old data sink becomes new data source. */
660 if (ds->sink != NULL)
661 ds->source = casewriter_make_reader (ds->sink);
666 ds->discard_output = false;
670 caseinit_clear (ds->caseinit);
671 caseinit_mark_as_preinited (ds->caseinit, ds->dict);
673 dict_clear_vectors (ds->dict);
674 ds->permanent_dict = NULL;
675 ds->order_var = NULL;
679 /* Casereader class for procedure execution. */
680 static const struct casereader_class proc_casereader_class =
682 proc_casereader_read,
683 proc_casereader_destroy,
688 /* Updates last_proc_invocation. */
690 update_last_proc_invocation (struct dataset *ds)
692 ds->last_proc_invocation = time (NULL);
695 /* Returns a pointer to the lagged case from N_BEFORE cases before the
696 current one, or NULL if there haven't been that many cases yet. */
698 lagged_case (const struct dataset *ds, int n_before)
700 assert (n_before >= 1);
701 assert (n_before <= ds->n_lag);
703 if (n_before <= deque_count (&ds->lag))
704 return ds->lag_cases[deque_front (&ds->lag, n_before - 1)];
709 /* Adds TRNS to the current set of transformations. */
711 add_transformation (struct dataset *ds,
712 const struct trns_class *class, void *aux)
714 struct trns_chain *chain = (ds->n_stack > 0 ? &ds->stack[ds->n_stack - 1]
715 : ds->temporary ? &ds->temporary_trns_chain
716 : &ds->permanent_trns_chain);
717 struct transformation t = { .class = class, .aux = aux };
718 trns_chain_append (chain, &t);
719 dataset_transformations_changed__ (ds, true);
722 /* Returns true if the next call to add_transformation() will add
723 a temporary transformation, false if it will add a permanent
726 proc_in_temporary_transformations (const struct dataset *ds)
728 return ds->temporary;
731 /* Marks the start of temporary transformations.
732 Further calls to add_transformation() will add temporary
735 proc_start_temporary_transformations (struct dataset *ds)
737 assert (!ds->n_stack);
738 if (!proc_in_temporary_transformations (ds))
740 add_case_limit_trns (ds);
742 ds->permanent_dict = dict_clone (ds->dict);
743 add_measurement_level_trns (ds, ds->permanent_dict);
745 ds->temporary = true;
746 dataset_transformations_changed__ (ds, true);
750 /* Converts all the temporary transformations, if any, to permanent
751 transformations. Further transformations will be permanent.
753 The FILTER command is implemented as a temporary transformation, so a
754 procedure that uses this function should usually use proc_open_filtering()
755 with FILTER false, instead of plain proc_open().
757 Returns true if anything changed, false otherwise. */
759 proc_make_temporary_transformations_permanent (struct dataset *ds)
761 if (proc_in_temporary_transformations (ds))
763 cancel_measurement_level_trns (&ds->permanent_trns_chain);
764 trns_chain_splice (&ds->permanent_trns_chain, &ds->temporary_trns_chain);
766 ds->temporary = false;
768 dict_unref (ds->permanent_dict);
769 ds->permanent_dict = NULL;
777 /* Cancels all temporary transformations, if any. Further
778 transformations will be permanent.
779 Returns true if anything changed, false otherwise. */
781 proc_cancel_temporary_transformations (struct dataset *ds)
783 if (proc_in_temporary_transformations (ds))
785 trns_chain_clear (&ds->temporary_trns_chain);
787 dict_unref (ds->dict);
788 ds->dict = ds->permanent_dict;
789 ds->permanent_dict = NULL;
791 dataset_transformations_changed__ (ds, ds->permanent_trns_chain.n != 0);
798 /* Cancels all transformations, if any.
799 Returns true if successful, false on I/O error. */
801 proc_cancel_all_transformations (struct dataset *ds)
804 assert (ds->proc_state == PROC_COMMITTED);
805 ok = trns_chain_clear (&ds->permanent_trns_chain);
806 ok = trns_chain_clear (&ds->temporary_trns_chain) && ok;
807 ds->temporary = false;
808 for (size_t i = 0; i < ds->n_stack; i++)
809 ok = trns_chain_uninit (&ds->stack[i]) && ok;
811 dataset_transformations_changed__ (ds, false);
817 proc_push_transformations (struct dataset *ds)
819 if (ds->n_stack >= ds->allocated_stack)
820 ds->stack = x2nrealloc (ds->stack, &ds->allocated_stack,
822 trns_chain_init (&ds->stack[ds->n_stack++]);
826 proc_pop_transformations (struct dataset *ds, struct trns_chain *chain)
828 assert (ds->n_stack > 0);
829 *chain = ds->stack[--ds->n_stack];
833 proc_has_transformations (const struct dataset *ds)
835 return ds->permanent_trns_chain.n || ds->temporary_trns_chain.n;
838 static enum trns_result
839 store_case_num (void *var_, struct ccase **cc, casenumber case_num)
841 struct variable *var = var_;
843 *cc = case_unshare (*cc);
844 *case_num_rw (*cc, var) = case_num;
846 return TRNS_CONTINUE;
849 /* Add a variable $ORDERING which we can sort by to get back the original order. */
851 add_permanent_ordering_transformation (struct dataset *ds)
853 struct dictionary *d = ds->permanent_dict ? ds->permanent_dict : ds->dict;
854 struct variable *order_var = dict_create_var_assert (d, "$ORDER", 0);
855 ds->order_var = order_var;
857 if (ds->permanent_dict)
859 order_var = dict_create_var_assert (ds->dict, "$ORDER", 0);
860 static const struct trns_class trns_class = {
862 .execute = store_case_num
864 const struct transformation t = { .class = &trns_class, .aux = order_var };
865 trns_chain_prepend (&ds->temporary_trns_chain, &t);
871 /* Causes output from the next procedure to be discarded, instead
872 of being preserved for use as input for the next procedure. */
874 proc_discard_output (struct dataset *ds)
876 ds->discard_output = true;
880 /* Checks whether DS has a corrupted active dataset. If so,
881 discards it and returns false. If not, returns true without
884 dataset_end_of_command (struct dataset *ds)
886 if (ds->source != NULL)
888 if (casereader_error (ds->source))
895 const struct taint *taint = casereader_get_taint (ds->source);
896 taint_reset_successor_taint (CONST_CAST (struct taint *, taint));
897 assert (!taint_has_tainted_successor (taint));
903 /* Limits the maximum number of cases processed to
905 static enum trns_result
906 case_limit_trns_proc (void *cases_remaining_,
907 struct ccase **c UNUSED, casenumber case_nr UNUSED)
909 size_t *cases_remaining = cases_remaining_;
910 if (*cases_remaining > 0)
912 (*cases_remaining)--;
913 return TRNS_CONTINUE;
916 return TRNS_DROP_CASE;
919 /* Frees the data associated with a case limit transformation. */
921 case_limit_trns_free (void *cases_remaining_)
923 size_t *cases_remaining = cases_remaining_;
924 free (cases_remaining);
928 /* Adds a transformation that limits the number of cases that may
929 pass through, if DS->DICT has a case limit. */
931 add_case_limit_trns (struct dataset *ds)
933 casenumber case_limit = dict_get_case_limit (ds->dict);
936 casenumber *cases_remaining = xmalloc (sizeof *cases_remaining);
937 *cases_remaining = case_limit;
939 static const struct trns_class trns_class = {
940 .name = "case limit",
941 .execute = case_limit_trns_proc,
942 .destroy = case_limit_trns_free,
944 add_transformation (ds, &trns_class, cases_remaining);
946 dict_set_case_limit (ds->dict, 0);
951 /* FILTER transformation. */
952 static enum trns_result
953 filter_trns_proc (void *filter_var_,
954 struct ccase **c, casenumber case_nr UNUSED)
957 struct variable *filter_var = filter_var_;
958 double f = case_num (*c, filter_var);
959 return (f != 0.0 && !var_is_num_missing (filter_var, f)
960 ? TRNS_CONTINUE : TRNS_DROP_CASE);
963 /* Adds a temporary transformation to filter data according to
964 the variable specified on FILTER, if any. */
966 add_filter_trns (struct dataset *ds)
968 struct variable *filter_var = dict_get_filter (ds->dict);
969 if (filter_var != NULL)
971 proc_start_temporary_transformations (ds);
973 static const struct trns_class trns_class = {
975 .execute = filter_trns_proc,
977 add_transformation (ds, &trns_class, filter_var);
982 dataset_need_lag (struct dataset *ds, int n_before)
984 ds->n_lag = MAX (ds->n_lag, n_before);
987 /* Measurement guesser, for guessing a measurement level from formats and
992 struct hmap_node hmap_node;
998 struct variable *var;
1003 mg_var_uninit (struct mg_var *mgv)
1005 struct mg_value *mgvalue, *next;
1006 HMAP_FOR_EACH_SAFE (mgvalue, next, struct mg_value, hmap_node,
1009 hmap_delete (mgv->values, &mgvalue->hmap_node);
1012 hmap_destroy (mgv->values);
1017 mg_var_interpret (const struct mg_var *mgv)
1019 size_t n = hmap_count (mgv->values);
1022 /* All missing (or no data). */
1023 return MEASURE_NOMINAL;
1026 const struct mg_value *mgvalue;
1027 HMAP_FOR_EACH (mgvalue, struct mg_value, hmap_node,
1029 if (mgvalue->value < 10)
1030 return MEASURE_NOMINAL;
1031 return MEASURE_SCALE;
1035 mg_var_add_value (struct mg_var *mgv, double value)
1037 if (var_is_num_missing (mgv->var, value))
1038 return MEASURE_UNKNOWN;
1039 else if (value < 0 || value != floor (value))
1040 return MEASURE_SCALE;
1042 size_t hash = hash_double (value, 0);
1043 struct mg_value *mgvalue;
1044 HMAP_FOR_EACH_WITH_HASH (mgvalue, struct mg_value, hmap_node,
1046 if (mgvalue->value == value)
1047 return MEASURE_UNKNOWN;
1049 mgvalue = xmalloc (sizeof *mgvalue);
1050 mgvalue->value = value;
1051 hmap_insert (mgv->values, &mgvalue->hmap_node, hash);
1052 if (hmap_count (mgv->values) >= settings_get_scalemin ())
1053 return MEASURE_SCALE;
1055 return MEASURE_UNKNOWN;
1058 struct measure_guesser
1060 struct mg_var *vars;
1064 static struct measure_guesser *
1065 measure_guesser_create__ (struct dictionary *dict)
1067 struct mg_var *mgvs = NULL;
1069 size_t allocated_mgvs = 0;
1071 for (size_t i = 0; i < dict_get_n_vars (dict); i++)
1073 struct variable *var = dict_get_var (dict, i);
1074 if (var_get_measure (var) != MEASURE_UNKNOWN)
1077 struct fmt_spec f = var_get_print_format (var);
1078 enum measure m = var_default_measure_for_format (f.type);
1079 if (m != MEASURE_UNKNOWN)
1081 var_set_measure (var, m);
1085 if (n_mgvs >= allocated_mgvs)
1086 mgvs = x2nrealloc (mgvs, &allocated_mgvs, sizeof *mgvs);
1088 struct mg_var *mgv = &mgvs[n_mgvs++];
1089 *mgv = (struct mg_var) {
1091 .values = xmalloc (sizeof *mgv->values),
1093 hmap_init (mgv->values);
1098 struct measure_guesser *mg = xmalloc (sizeof *mg);
1099 *mg = (struct measure_guesser) {
1106 /* Scans through DS's dictionary for variables that have an unknown measurement
1107 level. For those, if the measurement level can be guessed based on the
1108 variable's type and format, sets a default. If that's enough, returns NULL.
1109 If any remain whose levels are unknown and can't be guessed that way,
1110 creates and returns a structure that the caller should pass to
1111 measure_guesser_add_case() or measure_guesser_run() for guessing a
1112 measurement level based on the data. */
1113 struct measure_guesser *
1114 measure_guesser_create (struct dataset *ds)
1116 return measure_guesser_create__ (dataset_dict (ds));
1119 /* Adds data from case C to MG. */
1121 measure_guesser_add_case (struct measure_guesser *mg, const struct ccase *c)
1123 for (size_t i = 0; i < mg->n_vars; )
1125 struct mg_var *mgv = &mg->vars[i];
1126 double value = case_num (c, mgv->var);
1127 enum measure m = mg_var_add_value (mgv, value);
1128 if (m != MEASURE_UNKNOWN)
1130 var_set_measure (mgv->var, m);
1132 mg_var_uninit (mgv);
1133 *mgv = mg->vars[--mg->n_vars];
1142 measure_guesser_destroy (struct measure_guesser *mg)
1147 for (size_t i = 0; i < mg->n_vars; i++)
1149 struct mg_var *mgv = &mg->vars[i];
1150 var_set_measure (mgv->var, mg_var_interpret (mgv));
1151 mg_var_uninit (mgv);
1157 /* Adds final measurement levels based on MG, after all the cases have been
1160 measure_guesser_commit (struct measure_guesser *mg)
1162 for (size_t i = 0; i < mg->n_vars; i++)
1164 struct mg_var *mgv = &mg->vars[i];
1165 var_set_measure (mgv->var, mg_var_interpret (mgv));
1169 /* Passes the cases in READER through MG and uses the data in the cases to set
1170 measurement levels for the variables where they were still unknown. */
1172 measure_guesser_run (struct measure_guesser *mg,
1173 const struct casereader *reader)
1175 struct casereader *r = casereader_clone (reader);
1176 while (mg->n_vars > 0)
1178 struct ccase *c = casereader_read (r);
1181 measure_guesser_add_case (mg, c);
1184 casereader_destroy (r);
1186 measure_guesser_commit (mg);
1189 /* A transformation for guessing measurement levels. */
1191 static enum trns_result
1192 mg_trns_proc (void *mg_, struct ccase **c, casenumber case_nr UNUSED)
1194 struct measure_guesser *mg = mg_;
1195 measure_guesser_add_case (mg, *c);
1196 return TRNS_CONTINUE;
1200 mg_trns_free (void *mg_)
1202 struct measure_guesser *mg = mg_;
1203 measure_guesser_commit (mg);
1204 measure_guesser_destroy (mg);
1208 static const struct trns_class mg_trns_class = {
1209 .name = "add measurement level",
1210 .execute = mg_trns_proc,
1211 .destroy = mg_trns_free,
1215 add_measurement_level_trns (struct dataset *ds, struct dictionary *dict)
1217 struct measure_guesser *mg = measure_guesser_create__ (dict);
1219 add_transformation (ds, &mg_trns_class, mg);
1223 cancel_measurement_level_trns (struct trns_chain *chain)
1228 struct transformation *trns = &chain->xforms[chain->n - 1];
1229 if (trns->class != &mg_trns_class)
1232 struct measure_guesser *mg = trns->aux;
1233 measure_guesser_destroy (mg);
1238 dataset_changed__ (struct dataset *ds)
1240 if (ds->callbacks != NULL && ds->callbacks->changed != NULL)
1241 ds->callbacks->changed (ds->cb_data);
1245 dataset_transformations_changed__ (struct dataset *ds, bool non_empty)
1247 if (ds->callbacks != NULL && ds->callbacks->transformations_changed != NULL)
1248 ds->callbacks->transformations_changed (non_empty, ds->cb_data);
1251 /* Private interface for use by session code. */
1254 dataset_set_session__ (struct dataset *ds, struct session *session)
1256 ds->session = session;