X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fdata%2Fcasereader-translator.c;h=5c8b9f4209929f335c702f47e6f96312d8f1fabe;hb=refs%2Fheads%2Fdelete-variables;hp=feffa15c4510ba97e57cd95705cd9afd290c1e04;hpb=b40baf410822471fbdeeec553693619d60d7c7b6;p=pspp
diff --git a/src/data/casereader-translator.c b/src/data/casereader-translator.c
index feffa15c45..5c8b9f4209 100644
--- a/src/data/casereader-translator.c
+++ b/src/data/casereader-translator.c
@@ -1,5 +1,5 @@
/* PSPP - a program for statistical analysis.
- Copyright (C) 2007, 2009 Free Software Foundation, Inc.
+ Copyright (C) 2007, 2009, 2011 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
@@ -15,15 +15,16 @@
along with this program. If not, see . */
#include
-#include
-#include
+
#include
-#include
-#include
-#include
+#include "data/casereader-provider.h"
+#include "data/casereader.h"
+#include "data/val-type.h"
+#include "data/variable.h"
+#include "libpspp/taint.h"
-#include "xalloc.h"
+#include "gl/xalloc.h"
/* Casereader that applies a user-supplied function to translate
each case into another in an arbitrary fashion. */
@@ -32,9 +33,7 @@
struct casereader_translator
{
struct casereader *subreader; /* Source of input cases. */
-
- struct ccase *(*translate) (struct ccase *input, void *aux);
- bool (*destroy) (void *aux);
+ const struct casereader_translator_class *class;
void *aux;
};
@@ -46,6 +45,11 @@ static const struct casereader_class casereader_translator_class;
INPUT and auxiliary data AUX. TRANSLATE must destroy its
input case.
+ TRANSLATE may be stateful, that is, the output for a given
+ case may depend on previous cases. If TRANSLATE is stateless,
+ then you may want to use casereader_translate_stateless
+ instead, since it sometimes performs better.
+
The cases returned by TRANSLATE must match OUTPUT_PROTO.
When the translating casereader is destroyed, DESTROY will be
@@ -57,19 +61,18 @@ static const struct casereader_class casereader_translator_class;
struct casereader *
casereader_create_translator (struct casereader *subreader,
const struct caseproto *output_proto,
- struct ccase *(*translate) (struct ccase *input,
- void *aux),
- bool (*destroy) (void *aux),
+ const struct casereader_translator_class *class,
void *aux)
{
struct casereader_translator *ct = xmalloc (sizeof *ct);
- struct casereader *reader;
- ct->subreader = casereader_rename (subreader);
- ct->translate = translate;
- ct->destroy = destroy;
- ct->aux = aux;
- reader = casereader_create_sequential (
- NULL, output_proto, casereader_get_case_cnt (ct->subreader),
+ *ct = (struct casereader_translator) {
+ .subreader = casereader_rename (subreader),
+ .class = class,
+ .aux = aux,
+ };
+
+ struct casereader *reader = casereader_create_sequential (
+ NULL, output_proto, casereader_get_n_cases (ct->subreader),
&casereader_translator_class, ct);
taint_propagate (casereader_get_taint (ct->subreader),
casereader_get_taint (reader));
@@ -84,7 +87,7 @@ casereader_translator_read (struct casereader *reader UNUSED,
struct casereader_translator *ct = ct_;
struct ccase *tmp = casereader_read (ct->subreader);
if (tmp)
- tmp = ct->translate (tmp, ct->aux);
+ tmp = ct->class->translate (tmp, ct->aux);
return tmp;
}
@@ -94,7 +97,7 @@ casereader_translator_destroy (struct casereader *reader UNUSED, void *ct_)
{
struct casereader_translator *ct = ct_;
casereader_destroy (ct->subreader);
- ct->destroy (ct->aux);
+ ct->class->destroy (ct->aux);
free (ct);
}
@@ -106,7 +109,102 @@ static const struct casereader_class casereader_translator_class =
NULL,
NULL,
};
+
+/* Casereader that applies a user-supplied function to translate
+ each case into another in a stateless fashion. */
+
+/* A statelessly translating casereader. */
+struct casereader_stateless_translator
+ {
+ struct casereader *subreader; /* Source of input cases. */
+
+ casenumber case_offset;
+ const struct casereader_translator_class *class;
+ void *aux;
+ };
+static const struct casereader_random_class
+casereader_stateless_translator_class;
+
+/* Creates and returns a new casereader whose cases are produced by reading
+ from SUBREADER and passing through the TRANSLATE function. TRANSLATE must
+ takes ownership of its input case and returns a translated case, populating
+ the translated case based on INPUT and auxiliary data AUX.
+
+ TRANSLATE must be stateless, that is, the output for a given case must not
+ depend on previous cases. This is because cases may be retrieved in
+ arbitrary order, and some cases may be retrieved multiple times, and some
+ cases may be skipped and never retrieved at all. If TRANSLATE is stateful,
+ use casereader_create_translator instead.
+
+ The cases returned by TRANSLATE must match OUTPUT_PROTO.
+
+ When the stateless translating casereader is destroyed, DESTROY will be
+ called to allow any auxiliary data 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_translate_stateless (
+ struct casereader *subreader,
+ const struct caseproto *output_proto,
+ const struct casereader_translator_class *class,
+ void *aux)
+{
+ struct casereader_stateless_translator *cst = xmalloc (sizeof *cst);
+ *cst = (struct casereader_stateless_translator) {
+ .subreader = casereader_rename (subreader),
+ .class = class,
+ .aux = aux,
+ };
+ struct casereader *reader = casereader_create_random (
+ output_proto, casereader_get_n_cases (cst->subreader),
+ &casereader_stateless_translator_class, cst);
+ taint_propagate (casereader_get_taint (cst->subreader),
+ casereader_get_taint (reader));
+ return reader;
+}
+
+/* Internal read function for stateless translating casereader. */
+static struct ccase *
+casereader_stateless_translator_read (struct casereader *reader UNUSED,
+ void *cst_, casenumber idx)
+{
+ struct casereader_stateless_translator *cst = cst_;
+ struct ccase *tmp = casereader_peek (cst->subreader, idx);
+ if (tmp != NULL)
+ tmp = cst->class->translate (tmp, cst->aux);
+ return tmp;
+}
+
+/* Internal destroy function for translating casereader. */
+static void
+casereader_stateless_translator_destroy (struct casereader *reader UNUSED,
+ void *cst_)
+{
+ struct casereader_stateless_translator *cst = cst_;
+ casereader_destroy (cst->subreader);
+ cst->class->destroy (cst->aux);
+ free (cst);
+}
+
+static void
+casereader_stateless_translator_advance (struct casereader *reader UNUSED,
+ void *cst_, casenumber n)
+{
+ struct casereader_stateless_translator *cst = cst_;
+ cst->case_offset += casereader_advance (cst->subreader, n);
+}
+
+/* Casereader class for stateless translating casereader. */
+static const struct casereader_random_class
+casereader_stateless_translator_class =
+ {
+ casereader_stateless_translator_read,
+ casereader_stateless_translator_destroy,
+ casereader_stateless_translator_advance,
+ };
struct casereader_append_numeric
@@ -144,8 +242,11 @@ casereader_create_append_numeric (struct casereader *subreader,
can->aux = aux;
can->func = func;
can->destroy = destroy;
- return casereader_create_translator (subreader, can->proto,
- can_translate, can_destroy, can);
+
+ static const struct casereader_translator_class class = {
+ can_translate, can_destroy,
+ };
+ return casereader_create_translator (subreader, can->proto, &class, can);
}
@@ -155,7 +256,7 @@ can_translate (struct ccase *c, void *can_)
struct casereader_append_numeric *can = can_;
double new_value = can->func (c, can->n++, can->aux);
c = case_unshare_and_resize (c, can->proto);
- case_data_rw_idx (c, caseproto_get_n_widths (can->proto) - 1)->f = new_value;
+ *case_num_rw_idx (c, caseproto_get_n_widths (can->proto) - 1) = new_value;
return c;
}
@@ -200,7 +301,7 @@ struct casereader *
casereader_create_arithmetic_sequence (struct casereader *subreader,
double first, double increment)
{
- struct arithmetic_sequence *as = xzalloc (sizeof *as);
+ struct arithmetic_sequence *as = XZALLOC (struct arithmetic_sequence);
as->first = first;
as->increment = increment;
return casereader_create_append_numeric (subreader, next_arithmetic,
@@ -248,7 +349,7 @@ static struct ccase *car_translate (struct ccase *input, void *car_);
If DISTINCT_CALLBACK is non-null, then it will be called exactly
once for every case containing a distinct value of V. AUX is
- an auxilliary pointer passed to DISTINCT_CALLBACK.
+ an auxiliary pointer passed to DISTINCT_CALLBACK.
After this function is called, SUBREADER must not ever again
be referenced directly. It will be destroyed automatically
@@ -260,7 +361,7 @@ casereader_create_append_rank (struct casereader *subreader,
enum rank_error *err,
distinct_func *distinct_callback,
void *aux
- )
+ )
{
struct casereader_append_rank *car = xmalloc (sizeof *car);
car->proto = caseproto_ref (casereader_get_proto (subreader));
@@ -276,8 +377,10 @@ casereader_create_append_rank (struct casereader *subreader,
car->err = err;
car->prev_value = SYSMIS;
- return casereader_create_translator (subreader, car->proto,
- car_translate, car_destroy, car);
+ static const struct casereader_translator_class class = {
+ car_translate, car_destroy
+ };
+ return casereader_create_translator (subreader, car->proto, &class, car);
}
@@ -296,23 +399,23 @@ car_translate (struct ccase *input, void *car_)
{
struct casereader_append_rank *car = car_;
- const double value = case_data (input, car->var)->f;
+ const double value = case_num (input, car->var);
- if ( car->prev_value != SYSMIS)
+ if (car->prev_value != SYSMIS)
{
if (car->err && value < car->prev_value)
*car->err |= RANK_ERR_UNSORTED;
}
- if ( car->n_common == 1)
+ if (car->n_common == 1)
{
double vxx = SYSMIS;
casenumber k = 0;
double weight = 1.0;
if (car->weight)
{
- weight = case_data (input, car->weight)->f;
- if ( car->err && weight < 0 )
+ weight = case_num (input, car->weight);
+ if (car->err && weight < 0)
*car->err |= RANK_ERR_NEGATIVE_WEIGHT;
}
@@ -321,15 +424,15 @@ car_translate (struct ccase *input, void *car_)
struct ccase *c = casereader_peek (car->clone, car->n + ++k);
if (c == NULL)
break;
- vxx = case_data (c, car->var)->f;
+ vxx = case_num (c, car->var);
- if ( vxx == value)
+ if (vxx == value)
{
if (car->weight)
{
- double w = case_data (c, car->weight)->f;
+ double w = case_num (c, car->weight);
- if ( car->err && w < 0 )
+ if (car->err && w < 0)
*car->err |= RANK_ERR_NEGATIVE_WEIGHT;
weight += w;
@@ -353,7 +456,7 @@ car_translate (struct ccase *input, void *car_)
car->n++;
input = case_unshare_and_resize (input, car->proto);
- case_data_rw_idx (input, caseproto_get_n_widths (car->proto) - 1)->f
+ *case_num_rw_idx (input, caseproto_get_n_widths (car->proto) - 1)
= car->mean_rank;
car->prev_value = value;
return input;
@@ -381,26 +484,32 @@ uniquify (const struct ccase *c, void *aux)
struct consolidator *cdr = aux;
const union value *current_value = case_data (c, cdr->key);
const int key_width = var_get_width (cdr->key);
- const double weight = cdr->weight ? case_data (c, cdr->weight)->f : 1.0;
- const struct ccase *next_case = casereader_peek (cdr->clone, cdr->n + 1);
+ const double weight = cdr->weight ? case_num (c, cdr->weight) : 1.0;
+ struct ccase *next_case = casereader_peek (cdr->clone, cdr->n + 1);
int dir = 0;
cdr->n ++;
cdr->cc += weight;
- if ( NULL == next_case)
+ if (NULL == next_case)
goto end;
-
+
dir = value_compare_3way (case_data (next_case, cdr->key),
current_value, key_width);
- if ( dir != 0 )
+ if (dir > 0)
+ dir = 1;
+ if (dir < 0)
+ dir = -1;
+
+ case_unref (next_case);
+ if (dir != 0)
{
/* Insist that the data are sorted */
assert (cdr->direction == 0 || dir == cdr->direction);
cdr->direction = dir;
goto end;
}
-
+
return false;
end:
@@ -420,12 +529,12 @@ consolodate_weight (struct ccase *input, void *aux)
if (cdr->weight)
{
c = case_unshare (input);
- case_data_rw (c, cdr->weight)->f = cdr->prev_cc;
+ *case_num_rw (c, cdr->weight) = cdr->prev_cc;
}
else
{
c = case_unshare_and_resize (input, cdr->proto);
- case_data_rw_idx (c, caseproto_get_n_widths (cdr->proto) - 1)->f = cdr->prev_cc;
+ *case_num_rw_idx (c, caseproto_get_n_widths (cdr->proto) - 1) = cdr->prev_cc;
}
return c;
@@ -446,7 +555,7 @@ uniquify_destroy (void *aux)
-/* Returns a new casereader which is based upon INPUT, but which contains a maximum
+/* Returns a new casereader which is based upon INPUT, but which contains a maximum
of one case for each distinct value of KEY.
If WEIGHT is non-null, then the new casereader's values for this variable
will be the sum of all values matching KEY.
@@ -461,7 +570,6 @@ casereader_create_distinct (struct casereader *input,
const struct variable *weight)
{
struct casereader *u ;
- struct casereader *ud ;
struct caseproto *output_proto = caseproto_ref (casereader_get_proto (input));
struct consolidator *cdr = xmalloc (sizeof (*cdr));
@@ -472,7 +580,7 @@ casereader_create_distinct (struct casereader *input,
cdr->clone = casereader_clone (input);
cdr->direction = 0;
- if ( NULL == cdr->weight )
+ if (NULL == cdr->weight)
output_proto = caseproto_add_width (output_proto, 0);
cdr->proto = output_proto;
@@ -480,12 +588,9 @@ casereader_create_distinct (struct casereader *input,
u = casereader_create_filter_func (input, uniquify,
NULL, cdr, NULL);
- ud = casereader_create_translator (u,
- output_proto,
- consolodate_weight,
- uniquify_destroy,
- cdr);
-
- return ud;
+ static const struct casereader_translator_class class = {
+ consolodate_weight, uniquify_destroy,
+ };
+ return casereader_create_translator (u, output_proto, &class, cdr);
}