Changeset: 89aef7f4b1b8 for MonetDB
URL: http://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=89aef7f4b1b8
Modified Files:
gdk/gdk_sample.c
Branch: Oct2014
Log Message:
Layout.
diffs (163 lines):
diff --git a/gdk/gdk_sample.c b/gdk/gdk_sample.c
--- a/gdk/gdk_sample.c
+++ b/gdk/gdk_sample.c
@@ -21,17 +21,17 @@
* @a Lefteris Sidirourgos, Hannes Muehleisen
* @* Low level sample facilities
*
- * This sampling implementation generates a sorted set of OIDs by calling the
- * random number generator, and uses a binary tree to eliminate duplicates.
- * The elements of the tree are then used to create a sorted sample BAT.
- * This implementation has a logarithmic complexity that only depends on the
- * sample size.
+ * This sampling implementation generates a sorted set of OIDs by
+ * calling the random number generator, and uses a binary tree to
+ * eliminate duplicates. The elements of the tree are then used to
+ * create a sorted sample BAT. This implementation has a logarithmic
+ * complexity that only depends on the sample size.
*
- * There is a pathological case when the sample size is almost the size of the
BAT.
- * Then, many collisions occur and performance degrades. To catch this, we
- * switch to antiset semantics when the sample size is larger than half the BAT
- * size. Then, we generate the values that should be omitted from the sample.
- *
+ * There is a pathological case when the sample size is almost the
+ * size of the BAT. Then, many collisions occur and performance
+ * degrades. To catch this, we switch to antiset semantics when the
+ * sample size is larger than half the BAT size. Then, we generate the
+ * values that should be omitted from the sample.
*/
#include "monetdb_config.h"
@@ -62,9 +62,11 @@ struct oidtreenode {
struct oidtreenode* right;
};
+static struct oidtreenode *
+OIDTreeNew(BUN oid)
+{
+ struct oidtreenode *node = GDKmalloc(sizeof(struct oidtreenode));
-static struct oidtreenode* OIDTreeNew(BUN oid) {
- struct oidtreenode *node = GDKmalloc(sizeof(struct oidtreenode));
if (node == NULL) {
GDKerror("#BATsample: memory allocation error");
return NULL ;
@@ -72,7 +74,7 @@ static struct oidtreenode* OIDTreeNew(BU
node->oid = oid;
node->left = NULL;
node->right = NULL;
- return (node);
+ return node;
}
static int
@@ -92,7 +94,9 @@ OIDTreeMaybeInsert(struct oidtreenode**
}
/* inorder traversal, gives us a sorted BAT */
-static void OIDTreeToBAT(struct oidtreenode* node, BAT *bat) {
+static void
+OIDTreeToBAT(struct oidtreenode* node, BAT *bat)
+{
if (node->left != NULL)
OIDTreeToBAT(node->left, bat);
((oid *) bat->T->heap.base)[bat->batFirst + bat->batCount++] =
node->oid;
@@ -101,14 +105,17 @@ static void OIDTreeToBAT(struct oidtreen
}
/* Antiset traversal, give us all values but the ones in the tree */
-static void OIDTreeToBATAntiset(struct oidtreenode* node, BAT *bat, BUN start,
BUN stop) {
+static void
+OIDTreeToBATAntiset(struct oidtreenode* node, BAT *bat, BUN start, BUN stop)
+{
BUN noid;
+
if (node->left != NULL)
OIDTreeToBATAntiset(node->left, bat, start, node->oid);
- else
+ else
for (noid = start+1; noid < node->oid; noid++)
- ((oid *) bat->T->heap.base)[bat->batFirst +
bat->batCount++] = noid;
-
+ ((oid *) bat->T->heap.base)[bat->batFirst +
bat->batCount++] = noid;
+
if (node->right != NULL)
OIDTreeToBATAntiset(node->right, bat, node->oid, stop);
else
@@ -116,7 +123,9 @@ static void OIDTreeToBATAntiset(struct o
((oid *) bat->T->heap.base)[bat->batFirst +
bat->batCount++] = noid;
}
-static void OIDTreeDestroy(struct oidtreenode* node) {
+static void
+OIDTreeDestroy(struct oidtreenode* node)
+{
if (node == NULL) {
return;
}
@@ -132,11 +141,12 @@ static void OIDTreeDestroy(struct oidtre
/* BATsample implements sampling for void headed BATs */
BAT *
-BATsample(BAT *b, BUN n) {
+BATsample(BAT *b, BUN n)
+{
BAT *bn;
BUN cnt, slen;
BUN rescnt = 0;
- struct oidtreenode* tree = NULL;
+ struct oidtreenode *tree = NULL;
BATcheck(b, "BATsample");
assert(BAThdense(b));
@@ -169,13 +179,13 @@ BATsample(BAT *b, BUN n) {
BUN minoid = b->hseqbase;
BUN maxoid = b->hseqbase + cnt;
/* if someone samples more than half of our tree, we do the
antiset */
- bit antiset = n > cnt/2;
+ bit antiset = n > cnt / 2;
slen = n;
- if (antiset)
+ if (antiset)
n = cnt - n;
-
+
bn = BATnew(TYPE_void, TYPE_oid, slen, TRANSIENT);
- if (bn == NULL ) {
+ if (bn == NULL) {
GDKerror("#BATsample: memory allocation error");
return NULL;
}
@@ -185,13 +195,14 @@ BATsample(BAT *b, BUN n) {
int rc;
do {
/* generate a new random OID */
- /* coverity[dont_call] */
candoid = (BUN) (minoid + DRAND * (maxoid -
minoid));
- /* if that candidate OID was already generated,
try again */
+ /* if that candidate OID was already
+ * generated, try again */
} while ((rc = OIDTreeMaybeInsert(&tree, candoid)) ==
0);
if (rc < 0) {
GDKerror("#BATsample: memory allocation error");
- /* if malloc fails, we still need to clean up
the tree */
+ /* if malloc fails, we still need to
+ * clean up the tree */
OIDTreeDestroy(tree);
return NULL;
}
@@ -200,7 +211,7 @@ BATsample(BAT *b, BUN n) {
if (!antiset) {
OIDTreeToBAT(tree, bn);
} else {
- OIDTreeToBATAntiset(tree, bn, minoid-1, maxoid+1);
+ OIDTreeToBATAntiset(tree, bn, minoid - 1, maxoid + 1);
}
OIDTreeDestroy(tree);
@@ -219,4 +230,3 @@ BATsample(BAT *b, BUN n) {
}
return bn;
}
-
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