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The changes I have made are described in CHANGES. This was based on

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diffs to 7.3-devel and may not be applicable to 7.2. I have included a
change covered by a previous bugfix patch I submitted (the problem with
-.1 not being accepted by cube_in). It does not include a fix for the
potential buffer overrun issue I reported for cube_yyerror in
cubeparse.y.


Bruno Wolff III
This commit is contained in:
Bruce Momjian
2002-08-29 23:03:58 +00:00
parent 6d27cfdd89
commit 32784cddf1
8 changed files with 696 additions and 256 deletions
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52
contrib/cube/README.cube
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@ -99,7 +99,7 @@ Tokens
n [0-9]+
integer [+-]?{n}
real [+-]?({n}\.{n}?)|(\.{n})
real [+-]?({n}\.{n}?|\.{n})
FLOAT ({integer}|{real})([eE]{integer})?
O_BRACKET \[
C_BRACKET \]
@ -182,8 +182,8 @@ t
PRECISION
=========
Values are stored internally as 32-bit floating point numbers. This means that
numbers with more than 7 significant digits will be truncated.
Values are stored internally as 64-bit floating point numbers. This means that
numbers with more than about 16 significant digits will be truncated.
USAGE
@ -253,6 +253,44 @@ Other operators:
reasonably good sorting in most cases, which is useful if
you want to use ORDER BY with this type
The following functions are available:
cube_distance(cube, cube) returns double
cube_distance returns the distance between two cubes. If both cubes are
points, this is the normal distance function.
cube(text) returns cube
cube takes text input and returns a cube. This is useful for making cubes
from computed strings.
cube_dim(cube) returns int
cube_dim returns the number of dimensions stored in the the data structure
for a cube. This is useful for constraints on the dimensions of a cube.
cube_ll_coord(cube, int) returns double
cube_ll_coord returns the nth coordinate value for the lower left corner
of a cube. This is useful for doing coordinate transformations.
cube_ur_coord(cube, int) returns double
cube_ur_coord returns the nth coordinate value for the upper right corner
of a cube. This is useful for doing coordinate transformations.
cube_is_point(cube) returns bool
cube_is_point returns true if a cube is also a point. This is true when the
two defining corners are the same.
cube_enlarge(cube, double, int) returns cube
cube_enlarge increases the size of a cube by a specified radius in at least
n dimensions. If the radius is negative the box is shrunk instead. This
is useful for creating bounding boxes around a point for searching for
nearby points. All defined dimensions are changed by the radius. If n
is greater than the number of defined dimensions and the cube is being
increased (r >= 0) then 0 is used as the base for the extra coordinates.
LL coordinates are decreased by r and UR coordinates are increased by r. If
a LL coordinate is increased to larger than the corresponding UR coordinate
(this can only happen when r < 0) than both coordinates are set to their
average.
There are a few other potentially useful functions defined in cube.c
that vanished from the schema because I stopped using them. Some of
these were meant to support type casting. Let me know if I was wrong:
@ -287,3 +325,11 @@ Building 221
Argonne, IL 60439-4844
selkovjr@mcs.anl.gov
------------------------------------------------------------------------
Minor updates to this package were made by Bruno Wolff III <bruno@wolff.to>
in August of 2002.
These include changing the precision from single precision to double
precision and adding some new functions.