Hi,
I use the cube datatype a fair bit, and one thing I have always wanted
is the ability to do this:
pg=# select cube_from_arrays('{1,2,3}'::float[], '{3,5,6}'::float[]);
cube_from_arrays
---------------------
(1, 2, 3),(3, 5, 6)
(1 row)
That is - build a cube by specifying 2 arrays, one for the UR
coordinate, one for LL.
I hope people find this useful, and if so, we can add it to contrib/cube.
Source is attached.
Thanks,
Joshua Reich
(jdigittl on #postgresql)
#include "postgres.h"
#include "utils/array.h"
#include "cubedata.h" /* contrib/cube */
/*
** CREATE OR REPLACE FUNCTION cube_from_arrays(float[], float[]) RETURNS
cube
** AS 'ordermatch'
** LANGUAGE C;
*/
NDBOX *cube_from_arrays (ArrayType *ur, ArrayType *ll);
/*
** Taken from the intarray contrib header
*/
#define ARRPTR(x) ( (double *) ARR_DATA_PTR(x) )
#define ARRNELEMS(x) ArrayGetNItems( ARR_NDIM(x), ARR_DIMS(x))
/*
** Allows the construction of a cube from 2 float[]'s
*/
NDBOX *cube_from_arrays (ArrayType *ur, ArrayType *ll)
{
int i;
int dim;
int size;
NDBOX *result;
double *dur, *dll;
dim = ARRNELEMS(ur);
if (ARRNELEMS(ll) < dim)
{
/*
** If the array's are not of equal length, use the length
** of the shorter array.
*/
dim = ARRNELEMS(ll);
}
dur = ARRPTR(ur);
dll = ARRPTR(ll);
size = offsetof(NDBOX, x[0]) + sizeof(double) * 2 * dim;
result = (NDBOX *) palloc (size);
memset (result, 0, size);
result->size = size;
result->dim = dim;
for (i=0; i<dim; i++)
{
result->x[i] = dur[i];
result->x[i+dim] = dll[i];
}
return result;
}
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