1 /* PSPP - computes sample statistics.
2 Copyright (C) 1997-9, 2000 Free Software Foundation, Inc.
3 Written by Ben Pfaff <blp@gnu.org>.
5 This program is free software; you can redistribute it and/or
6 modify it under the terms of the GNU General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 This program is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
24 #include <data/case.h>
25 #include <data/dictionary.h>
26 #include <data/procedure.h>
27 #include <data/transformations.h>
28 #include <data/variable.h>
29 #include <language/command.h>
30 #include <language/expressions/public.h>
31 #include <language/lexer/lexer.h>
32 #include <libpspp/alloc.h>
33 #include <libpspp/message.h>
34 #include <libpspp/message.h>
35 #include <libpspp/misc.h>
36 #include <libpspp/str.h>
39 #define _(msgid) gettext (msgid)
44 /* Target of a COMPUTE or IF assignment, either a variable or a
46 static struct lvalue *lvalue_parse (void);
47 static int lvalue_get_type (const struct lvalue *);
48 static bool lvalue_is_vector (const struct lvalue *);
49 static void lvalue_finalize (struct lvalue *,
50 struct compute_trns *);
51 static void lvalue_destroy (struct lvalue *);
53 /* COMPUTE and IF transformation. */
56 /* Test expression (IF only). */
57 struct expression *test; /* Test expression. */
59 /* Variable lvalue, if variable != NULL. */
60 struct variable *variable; /* Destination variable, if any. */
61 int fv; /* `value' index of destination variable. */
62 int width; /* Lvalue string width; 0=numeric. */
64 /* Vector lvalue, if vector != NULL. */
65 const struct vector *vector; /* Destination vector, if any. */
66 struct expression *element; /* Destination vector element expr. */
69 struct expression *rvalue; /* Rvalue expression. */
72 static struct expression *parse_rvalue (const struct lvalue *);
73 static struct compute_trns *compute_trns_create (void);
74 static trns_proc_func *get_proc_func (const struct lvalue *);
75 static trns_free_func compute_trns_free;
82 struct lvalue *lvalue = NULL;
83 struct compute_trns *compute = NULL;
85 compute = compute_trns_create ();
87 lvalue = lvalue_parse ();
91 if (!lex_force_match ('='))
93 compute->rvalue = parse_rvalue (lvalue);
94 if (compute->rvalue == NULL)
97 add_transformation (get_proc_func (lvalue), compute_trns_free, compute);
99 lvalue_finalize (lvalue, compute);
101 return lex_end_of_command ();
104 lvalue_destroy (lvalue);
105 compute_trns_free (compute);
106 return CMD_CASCADING_FAILURE;
109 /* Transformation functions. */
111 /* Handle COMPUTE or IF with numeric target variable. */
113 compute_num (void *compute_, struct ccase *c, int case_num)
115 struct compute_trns *compute = compute_;
117 if (compute->test == NULL
118 || expr_evaluate_num (compute->test, c, case_num) == 1.0)
119 case_data_rw (c, compute->fv)->f = expr_evaluate_num (compute->rvalue, c,
122 return TRNS_CONTINUE;
125 /* Handle COMPUTE or IF with numeric vector element target
128 compute_num_vec (void *compute_, struct ccase *c, int case_num)
130 struct compute_trns *compute = compute_;
132 if (compute->test == NULL
133 || expr_evaluate_num (compute->test, c, case_num) == 1.0)
135 double index; /* Index into the vector. */
136 int rindx; /* Rounded index value. */
138 index = expr_evaluate_num (compute->element, c, case_num);
139 rindx = floor (index + EPSILON);
140 if (index == SYSMIS || rindx < 1 || rindx > compute->vector->cnt)
143 msg (SW, _("When executing COMPUTE: SYSMIS is not a valid value as "
144 "an index into vector %s."), compute->vector->name);
146 msg (SW, _("When executing COMPUTE: %g is not a valid value as "
147 "an index into vector %s."),
148 index, compute->vector->name);
149 return TRNS_CONTINUE;
151 case_data_rw (c, compute->vector->var[rindx - 1]->fv)->f
152 = expr_evaluate_num (compute->rvalue, c, case_num);
155 return TRNS_CONTINUE;
158 /* Handle COMPUTE or IF with string target variable. */
160 compute_str (void *compute_, struct ccase *c, int case_num)
162 struct compute_trns *compute = compute_;
164 if (compute->test == NULL
165 || expr_evaluate_num (compute->test, c, case_num) == 1.0)
166 expr_evaluate_str (compute->rvalue, c, case_num,
167 case_data_rw (c, compute->fv)->s, compute->width);
169 return TRNS_CONTINUE;
172 /* Handle COMPUTE or IF with string vector element target
175 compute_str_vec (void *compute_, struct ccase *c, int case_num)
177 struct compute_trns *compute = compute_;
179 if (compute->test == NULL
180 || expr_evaluate_num (compute->test, c, case_num) == 1.0)
182 double index; /* Index into the vector. */
183 int rindx; /* Rounded index value. */
184 struct variable *vr; /* Variable reference by indexed vector. */
186 index = expr_evaluate_num (compute->element, c, case_num);
187 rindx = floor (index + EPSILON);
190 msg (SW, _("When executing COMPUTE: SYSMIS is not a valid "
191 "value as an index into vector %s."),
192 compute->vector->name);
193 return TRNS_CONTINUE;
195 else if (rindx < 1 || rindx > compute->vector->cnt)
197 msg (SW, _("When executing COMPUTE: %g is not a valid value as "
198 "an index into vector %s."),
199 index, compute->vector->name);
200 return TRNS_CONTINUE;
203 vr = compute->vector->var[rindx - 1];
204 expr_evaluate_str (compute->rvalue, c, case_num,
205 case_data_rw (c, vr->fv)->s, vr->width);
208 return TRNS_CONTINUE;
216 struct compute_trns *compute = NULL;
217 struct lvalue *lvalue = NULL;
219 compute = compute_trns_create ();
221 /* Test expression. */
222 compute->test = expr_parse (default_dict, EXPR_BOOLEAN);
223 if (compute->test == NULL)
226 /* Lvalue variable. */
227 lvalue = lvalue_parse ();
231 /* Rvalue expression. */
232 if (!lex_force_match ('='))
234 compute->rvalue = parse_rvalue (lvalue);
235 if (compute->rvalue == NULL)
238 add_transformation (get_proc_func (lvalue), compute_trns_free, compute);
240 lvalue_finalize (lvalue, compute);
242 return lex_end_of_command ();
245 lvalue_destroy (lvalue);
246 compute_trns_free (compute);
247 return CMD_CASCADING_FAILURE;
250 /* Code common to COMPUTE and IF. */
252 static trns_proc_func *
253 get_proc_func (const struct lvalue *lvalue)
255 bool is_numeric = lvalue_get_type (lvalue) == NUMERIC;
256 bool is_vector = lvalue_is_vector (lvalue);
259 ? (is_vector ? compute_num_vec : compute_num)
260 : (is_vector ? compute_str_vec : compute_str));
263 /* Parses and returns an rvalue expression of the same type as
264 LVALUE, or a null pointer on failure. */
265 static struct expression *
266 parse_rvalue (const struct lvalue *lvalue)
268 bool is_numeric = lvalue_get_type (lvalue) == NUMERIC;
270 return expr_parse (default_dict, is_numeric ? EXPR_NUMBER : EXPR_STRING);
273 /* Returns a new struct compute_trns after initializing its fields. */
274 static struct compute_trns *
275 compute_trns_create (void)
277 struct compute_trns *compute = xmalloc (sizeof *compute);
278 compute->test = NULL;
279 compute->variable = NULL;
280 compute->vector = NULL;
281 compute->element = NULL;
282 compute->rvalue = NULL;
286 /* Deletes all the fields in COMPUTE. */
288 compute_trns_free (void *compute_)
290 struct compute_trns *compute = compute_;
294 expr_free (compute->test);
295 expr_free (compute->element);
296 expr_free (compute->rvalue);
302 /* COMPUTE or IF target variable or vector element. */
305 char var_name[LONG_NAME_LEN + 1]; /* Destination variable name, or "". */
306 const struct vector *vector; /* Destination vector, if any, or NULL. */
307 struct expression *element; /* Destination vector element, or NULL. */
310 /* Parses the target variable or vector element into a new
311 `struct lvalue', which is returned. */
312 static struct lvalue *
315 struct lvalue *lvalue;
317 lvalue = xmalloc (sizeof *lvalue);
318 lvalue->var_name[0] = '\0';
319 lvalue->vector = NULL;
320 lvalue->element = NULL;
322 if (!lex_force_id ())
325 if (lex_look_ahead () == '(')
328 lvalue->vector = dict_lookup_vector (default_dict, tokid);
329 if (lvalue->vector == NULL)
331 msg (SE, _("There is no vector named %s."), tokid);
335 /* Vector element. */
337 if (!lex_force_match ('('))
339 lvalue->element = expr_parse (default_dict, EXPR_NUMBER);
340 if (lvalue->element == NULL)
342 if (!lex_force_match (')'))
348 str_copy_trunc (lvalue->var_name, sizeof lvalue->var_name, tokid);
354 lvalue_destroy (lvalue);
358 /* Returns the type (NUMERIC or ALPHA) of the target variable or
361 lvalue_get_type (const struct lvalue *lvalue)
363 if (lvalue->vector == NULL)
365 struct variable *var = dict_lookup_var (default_dict, lvalue->var_name);
372 return lvalue->vector->var[0]->type;
375 /* Returns nonzero if LVALUE has a vector as its target. */
377 lvalue_is_vector (const struct lvalue *lvalue)
379 return lvalue->vector != NULL;
382 /* Finalizes making LVALUE the target of COMPUTE, by creating the
383 target variable if necessary and setting fields in COMPUTE. */
385 lvalue_finalize (struct lvalue *lvalue, struct compute_trns *compute)
387 if (lvalue->vector == NULL)
389 compute->variable = dict_lookup_var (default_dict, lvalue->var_name);
390 if (compute->variable == NULL)
391 compute->variable = dict_create_var_assert (default_dict,
392 lvalue->var_name, 0);
394 compute->fv = compute->variable->fv;
395 compute->width = compute->variable->width;
397 /* Goofy behavior, but compatible: Turn off LEAVE. */
398 if (dict_class_from_id (compute->variable->name) != DC_SCRATCH)
399 compute->variable->leave = false;
403 compute->vector = lvalue->vector;
404 compute->element = lvalue->element;
405 lvalue->element = NULL;
408 lvalue_destroy (lvalue);
411 /* Destroys LVALUE. */
413 lvalue_destroy (struct lvalue *lvalue)
418 expr_free (lvalue->element);