X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fdata%2Fcasereader-translator.c;h=0557b65e8d6336452b4b88c4881d901fc289c7f2;hb=b65cf0519aa1db140d30c878978f29b1e23c9cd0;hp=f41dbb56fbc331af8adab5c6b93b472f09325158;hpb=ed88deded6a59254dd55883308c4c20966efc77e;p=pspp-builds.git
diff --git a/src/data/casereader-translator.c b/src/data/casereader-translator.c
index f41dbb56..0557b65e 100644
--- a/src/data/casereader-translator.c
+++ b/src/data/casereader-translator.c
@@ -1,20 +1,18 @@
-/* PSPP - computes sample statistics.
+/* PSPP - a program for statistical analysis.
Copyright (C) 2007 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
- This program is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- 02110-1301, USA. */
+ along with this program. If not, see . */
#include
@@ -27,26 +25,41 @@
#include "xalloc.h"
+/* Casereader that applies a user-supplied function to translate
+ each case into another in an arbitrary fashion. */
+
+/* A translating casereader. */
struct casereader_translator
{
- struct casereader *subreader;
+ struct casereader *subreader; /* Source of input cases. */
- void (*translate) (const struct ccase *input, struct ccase *output,
- void *aux);
+ void (*translate) (struct ccase *input, struct ccase *output, void *aux);
bool (*destroy) (void *aux);
void *aux;
};
-static struct casereader_class casereader_translator_class;
+static const struct casereader_class casereader_translator_class;
+
+/* Creates and returns a new casereader whose cases are produced
+ by reading from SUBREADER and passing through TRANSLATE, which
+ must create case OUTPUT, with OUTPUT_VALUE_CNT values, and
+ populate it based on INPUT and auxiliary data AUX. TRANSLATE
+ must also destroy INPUT.
+ When the translating casereader is destroyed, DESTROY will be
+ called to allow any state maintained by TRANSLATE to be freed.
+
+ After this function is called, SUBREADER must not ever again
+ be referenced directly. It will be destroyed automatically
+ when the translating casereader is destroyed. */
struct casereader *
casereader_create_translator (struct casereader *subreader,
size_t output_value_cnt,
- void (*translate) (const struct ccase *input,
+ void (*translate) (struct ccase *input,
struct ccase *output,
void *aux),
bool (*destroy) (void *aux),
- void *aux)
+ void *aux)
{
struct casereader_translator *ct = xmalloc (sizeof *ct);
struct casereader *reader;
@@ -62,24 +75,26 @@ casereader_create_translator (struct casereader *subreader,
return reader;
}
+/* Internal read function for translating casereader. */
static bool
casereader_translator_read (struct casereader *reader UNUSED,
- void *ct_, struct ccase *c)
+ void *ct_, struct ccase *c)
{
struct casereader_translator *ct = ct_;
struct ccase tmp;
- if (casereader_read (ct->subreader, &tmp))
+ if (casereader_read (ct->subreader, &tmp))
{
ct->translate (&tmp, c, ct->aux);
- return true;
+ return true;
}
else
return false;
}
+/* Internal destroy function for translating casereader. */
static void
-casereader_translator_destroy (struct casereader *reader UNUSED, void *ct_)
+casereader_translator_destroy (struct casereader *reader UNUSED, void *ct_)
{
struct casereader_translator *ct = ct_;
casereader_destroy (ct->subreader);
@@ -87,10 +102,112 @@ casereader_translator_destroy (struct casereader *reader UNUSED, void *ct_)
free (ct);
}
-static struct casereader_class casereader_translator_class =
+/* Casereader class for translating casereader. */
+static const struct casereader_class casereader_translator_class =
{
casereader_translator_read,
casereader_translator_destroy,
NULL,
NULL,
};
+
+
+
+struct casereader_append_numeric
+{
+ int value_ofs;
+ casenumber n;
+ new_value_func *func;
+ void *aux;
+ void (*destroy) (void *aux);
+};
+
+static bool can_destroy (void *can_);
+
+static void can_translate (struct ccase *input, struct ccase *output,
+ void *can_);
+
+/* Creates and returns a new casereader whose cases are produced
+ by reading from SUBREADER and appending an additional value,
+ generated by FUNC. AUX is an optional parameter which
+ gets passed to FUNC. FUNC will also receive N as it, which is
+ the ordinal number of the case in the reader. DESTROY is an
+ optional parameter used to destroy AUX.
+
+ After this function is called, SUBREADER must not ever again
+ be referenced directly. It will be destroyed automatically
+ when the translating casereader is destroyed. */
+struct casereader *
+casereader_create_append_numeric (struct casereader *subreader,
+ new_value_func func, void *aux,
+ void (*destroy) (void *aux))
+{
+ struct casereader_append_numeric *can = xmalloc (sizeof *can);
+ can->value_ofs = casereader_get_value_cnt (subreader);
+ can->n = 0;
+ can->aux = aux;
+ can->func = func;
+ can->destroy = destroy;
+ return casereader_create_translator (subreader, can->value_ofs + 1,
+ can_translate, can_destroy, can);
+}
+
+
+static void
+can_translate (struct ccase *input, struct ccase *output, void *can_)
+{
+ struct casereader_append_numeric *can = can_;
+ double new_value = can->func (input, can->n++, can->aux);
+ case_nullify (output);
+ case_move (output, input);
+ case_resize (output, can->value_ofs + 1);
+ case_data_rw_idx (output, can->value_ofs)->f = new_value;
+}
+
+static bool
+can_destroy (void *can_)
+{
+ struct casereader_append_numeric *can = can_;
+ if (can->destroy)
+ can->destroy (can->aux);
+ free (can);
+ return true;
+}
+
+
+
+struct arithmetic_sequence
+{
+ double first;
+ double increment;
+};
+
+static double
+next_arithmetic (const struct ccase *c UNUSED,
+ casenumber n,
+ void *aux)
+{
+ struct arithmetic_sequence *as = aux;
+ return n * as->increment + as->first;
+}
+
+/* Creates and returns a new casereader whose cases are produced
+ by reading from SUBREADER and appending an additional value,
+ which takes the value FIRST in the first case, FIRST +
+ INCREMENT in the second case, FIRST + INCREMENT * 2 in the
+ third case, and so on.
+
+ After this function is called, SUBREADER must not ever again
+ be referenced directly. It will be destroyed automatically
+ when the translating casereader is destroyed. */
+struct casereader *
+casereader_create_arithmetic_sequence (struct casereader *subreader,
+ double first, double increment)
+{
+ struct arithmetic_sequence *as = xzalloc (sizeof *as);
+ as->first = first;
+ as->increment = increment;
+ return casereader_create_append_numeric (subreader, next_arithmetic,
+ as, free);
+}
+