ST_SetValues

ST_SetValues
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名称

ST_SetValues — 返回通过设置给定波段的值而产生的修改后的栅格。

大纲

raster ST_SetValues(raster rast, integer nband, integer columnx, integer rowy, double precision[][] newvalueset, boolean[][] noset=NULL, boolean keepnodata=FALSE);

raster ST_SetValues(raster rast, integer nband, integer columnx, integer rowy, double precision[][] newvalueset, double precision nosetvalue, boolean keepnodata=FALSE);

raster ST_SetValues(raster rast, integer nband, integer columnx, integer rowy, integer width, integer height, double precision newvalue, boolean keepnodata=FALSE);

raster ST_SetValues(raster rast, integer columnx, integer rowy, integer width, integer height, double precision newvalue, boolean keepnodata=FALSE);

raster ST_SetValues(raster rast, integer nband, geomval[] geomvalset, boolean keepnodata=FALSE);

Description

返回通过将指定波段的指定像素设置为新值而产生的修改后的栅格。 columnx 和 rowy 是从1 开始索引的。

如果keepnodata为TRUE，那些值为NODATA的像素将不会被设置为newvalueset中的相应值。

对于变体1，要设置的特定像素由columnx、rowy像素坐标和newvalueset数组的尺寸决定。noset可以用来防止设置具有newvalueset中存在的值的像素（因为PostgreSQL不允许不规则数组）。请参见变体1的示例。

变体2与变体1类似，但是使用简单的双精度nosetvalue而不是布尔型的noset数组。newvalueset中具有nosetvalue值的元素将被跳过。请参见变体2的示例。

对于变体3，要设置的特定像素由columnx、rowy像素坐标、width和height决定。请参见变体3的示例。

变体4与变体3相同，唯一的区别是它假定将设置rast的第一个波段的像素。

对于变体5，将使用geomval数组来确定要设置的特定像素。如果数组中的所有几何图形都是点类型或多点类型，函数将使用一种快捷方式，其中每个点的经度和纬度用于直接设置像素。否则，几何图形将转换为栅格，然后一次迭代通过它们。请参见变体5的示例。

可用性：2.1.0

示例

Variant 1.

These examples pass FALSE for exclude_nodata_value so that every raster cell remains visible. NODATA cells display the band's NODATA value, which is 0 here.

Set the lower-right 2 by 2 block of a 3 by 3 raster to 9.

Code

SELECT
    (poly).x,
    (poly).y,
    (poly).val
FROM (
SELECT
    ST_PixelAsPolygons(ST_SetValues(ST_AddBand(ST_MakeEmptyRaster(3, 3, 0, 0, 1, -1, 0, 0, 0),
                1, '8BUI', 1, 0
            ),
            1, 2, 2, ARRAY[[9, 9], [9, 9]]::double precision[][]
        ),
        1, FALSE
    ) AS poly
) foo
ORDER BY 1, 2;

栅格输出

 x | y | val
---+---+-----
 1 | 1 |   1
 1 | 2 |   1
 1 | 3 |   1
 2 | 1 |   1
 2 | 2 |   9
 2 | 3 |   9
 3 | 1 |   1
 3 | 2 |   9
 3 | 3 |   9

Replace the complete raster from an array; the central NULL becomes NODATA.

Code

SELECT
    (poly).x,
    (poly).y,
    (poly).val
FROM (
SELECT
    ST_PixelAsPolygons(ST_SetValues(ST_AddBand(ST_MakeEmptyRaster(3, 3, 0, 0, 1, -1, 0, 0, 0),
                1, '8BUI', 1, 0
            ),
            1, 1, 1, ARRAY[[9, 9, 9], [9, NULL, 9], [9, 9, 9]]::double precision[][]
        ),
        1, FALSE
    ) AS poly
) foo
ORDER BY 1, 2;

栅格输出

 x | y | val
---+---+-----
 1 | 1 |   9
 1 | 2 |   9
 1 | 3 |   9
 2 | 1 |   9
 2 | 2 |   0
 2 | 3 |   9
 3 | 1 |   9
 3 | 2 |   9
 3 | 3 |   9

Use the noset mask to retain the left-middle source pixel while replacing the other cells.

Code

SELECT
    (poly).x,
    (poly).y,
    (poly).val
FROM (
SELECT
    ST_PixelAsPolygons(ST_SetValues(ST_AddBand(ST_MakeEmptyRaster(3, 3, 0, 0, 1, -1, 0, 0, 0),
                1, '8BUI', 1, 0
            ),
            1, 1, 1,
                ARRAY[[9, 9, 9], [9, NULL, 9], [9, 9, 9]]::double precision[][],
                ARRAY[[false], [true]]::boolean[][]
        ),
        1, FALSE
    ) AS poly
) foo
ORDER BY 1, 2;

栅格输出

x | y | val
---+---+-----
 1 | 1 |   9
 1 | 2 |   1
 1 | 3 |   9
 2 | 1 |   9
 2 | 2 |   0
 2 | 3 |   9
 3 | 1 |   9
 3 | 2 |   9
 3 | 3 |   9

With keepnodata enabled, an existing NODATA pixel is not overwritten.

Code

SELECT
    (poly).x,
    (poly).y,
    (poly).val
FROM (
SELECT
    ST_PixelAsPolygons(ST_SetValues(ST_SetValue(ST_AddBand(ST_MakeEmptyRaster(3, 3, 0, 0, 1, -1, 0, 0, 0),
                    1, '8BUI', 1, 0
                ),
                1, 1, 1, NULL
            ),
            1, 1, 1,
                ARRAY[[9, 9, 9], [9, NULL, 9], [9, 9, 9]]::double precision[][],
                ARRAY[[false], [true]]::boolean[][],
                TRUE
        ),
        1, FALSE
    ) AS poly
) foo
ORDER BY 1, 2;

栅格输出

x | y | val
---+---+-----
 1 | 1 |   0
 1 | 2 |   1
 1 | 3 |   9
 2 | 1 |   9
 2 | 2 |   0
 2 | 3 |   9
 3 | 1 |   9
 3 | 2 |   9
 3 | 3 |   9

Variant 2.

Use -1 as the value that should not be written; only the lower-right 2 by 2 block changes.

Code

SELECT
    (poly).x,
    (poly).y,
    (poly).val
FROM (
SELECT
    ST_PixelAsPolygons(ST_SetValues(ST_AddBand(ST_MakeEmptyRaster(3, 3, 0, 0, 1, -1, 0, 0, 0),
                1, '8BUI', 1, 0
            ),
            1, 1, 1, ARRAY[[-1, -1, -1], [-1, 9, 9], [-1, 9, 9]]::double precision[][], -1
        ),
        1, FALSE
    ) AS poly
) foo
ORDER BY 1, 2;

栅格输出

x | y | val
---+---+-----
 1 | 1 |   1
 1 | 2 |   1
 1 | 3 |   1
 2 | 1 |   1
 2 | 2 |   9
 2 | 3 |   9
 3 | 1 |   1
 3 | 2 |   9
 3 | 3 |   9

The same update can use NULL as the value that should not be written.

Code

SELECT
    (poly).x,
    (poly).y,
    (poly).val
FROM (
SELECT
    ST_PixelAsPolygons(ST_SetValues(ST_AddBand(ST_MakeEmptyRaster(3, 3, 0, 0, 1, -1, 0, 0, 0),
                1, '8BUI', 1, 0
            ),
            1, 1, 1, ARRAY[[NULL, NULL, NULL], [NULL, 9, 9], [NULL, 9, 9]]::double precision[][], NULL::double precision
        ),
        1, FALSE
    ) AS poly
) foo
ORDER BY 1, 2;

栅格输出

x | y | val
---+---+-----
 1 | 1 |   1
 1 | 2 |   1
 1 | 3 |   1
 2 | 1 |   1
 2 | 2 |   9
 2 | 3 |   9
 3 | 1 |   1
 3 | 2 |   9
 3 | 3 |   9

Variant 3.

Set a 2 by 2 rectangle starting at column 2, row 2.

Code

SELECT
    (poly).x,
    (poly).y,
    (poly).val
FROM (
SELECT
    ST_PixelAsPolygons(ST_SetValues(ST_AddBand(ST_MakeEmptyRaster(3, 3, 0, 0, 1, -1, 0, 0, 0),
                1, '8BUI', 1, 0
            ),
            1, 2, 2, 2, 2, 9
        ),
        1, FALSE
    ) AS poly
) foo
ORDER BY 1, 2;

栅格输出

x | y | val
---+---+-----
 1 | 1 |   1
 1 | 2 |   1
 1 | 3 |   1
 2 | 1 |   1
 2 | 2 |   9
 2 | 3 |   9
 3 | 1 |   1
 3 | 2 |   9
 3 | 3 |   9

When keepnodata is true, the NODATA cell inside the rectangle remains unchanged.

Code

SELECT
    (poly).x,
    (poly).y,
    (poly).val
FROM (
SELECT
    ST_PixelAsPolygons(ST_SetValues(ST_SetValue(ST_AddBand(ST_MakeEmptyRaster(3, 3, 0, 0, 1, -1, 0, 0, 0),
                    1, '8BUI', 1, 0
                ),
                1, 2, 2, NULL
            ),
            1, 2, 2, 2, 2, 9, TRUE
        ),
        1, FALSE
    ) AS poly
) foo
ORDER BY 1, 2;

栅格输出

x | y | val
---+---+-----
 1 | 1 |   1
 1 | 2 |   1
 1 | 3 |   1
 2 | 1 |   1
 2 | 2 |   0
 2 | 3 |   9
 3 | 1 |   1
 3 | 2 |   9
 3 | 3 |   9

Variant 5.

Code

WITH foo AS (
    SELECT 1 AS rid, ST_AddBand(ST_MakeEmptyRaster(5, 5, 0, 0, 1, -1, 0, 0, 0), 1, '8BUI', 0, 0) AS rast
), bar AS (
    SELECT 1 AS gid, 'SRID=0;POINT(2.5 -2.5)'::geometry geom UNION ALL
    SELECT 2 AS gid, 'SRID=0;POLYGON((1 -1,4 -1,4 -4,1 -4,1 -1))'::geometry geom UNION ALL
    SELECT 3 AS gid, 'SRID=0;POLYGON((0 0,5 0,5 -1,1 -1,1 -4,0 -4,0 0))'::geometry geom UNION ALL
    SELECT 4 AS gid, 'SRID=0;MULTIPOINT(0 0,4 4,4 -4)'::geometry
), changed AS (
    SELECT rid, gid, ST_SetValue(rast, 1, geom, gid) AS rast
    FROM foo
    CROSS JOIN bar
)
SELECT
    rid,
    gid,
    y,
    array_agg(ST_Value(rast, 1, x, y) ORDER BY x) AS values
FROM changed
CROSS JOIN generate_series(1, 5) AS x
CROSS JOIN generate_series(1, 5) AS y
GROUP BY rid, gid, y
ORDER BY rid, gid, y;

栅格输出

rid | gid | y |           values
-----+-----+---+----------------------------
   1 |   1 | 1 | {NULL,NULL,NULL,NULL,NULL}
   1 |   1 | 2 | {NULL,NULL,NULL,NULL,NULL}
   1 |   1 | 3 | {NULL,NULL,1,NULL,NULL}
   1 |   1 | 4 | {NULL,NULL,NULL,NULL,NULL}
   1 |   1 | 5 | {NULL,NULL,NULL,NULL,NULL}
   1 |   2 | 1 | {NULL,NULL,NULL,NULL,NULL}
   1 |   2 | 2 | {NULL,2,2,2,NULL}
   1 |   2 | 3 | {NULL,2,2,2,NULL}
   1 |   2 | 4 | {NULL,2,2,2,NULL}
   1 |   2 | 5 | {NULL,NULL,NULL,NULL,NULL}
   1 |   3 | 1 | {3,3,3,3,3}
   1 |   3 | 2 | {3,NULL,NULL,NULL,NULL}
   1 |   3 | 3 | {3,NULL,NULL,NULL,NULL}
   1 |   3 | 4 | {3,NULL,NULL,NULL,NULL}
   1 |   3 | 5 | {NULL,NULL,NULL,NULL,NULL}
   1 |   4 | 1 | {4,NULL,NULL,NULL,NULL}
   1 |   4 | 2 | {NULL,NULL,NULL,NULL,NULL}
   1 |   4 | 3 | {NULL,NULL,NULL,NULL,NULL}
   1 |   4 | 4 | {NULL,NULL,NULL,NULL,NULL}
   1 |   4 | 5 | {NULL,NULL,NULL,NULL,4}
(20 rows)

下面显示了数组中后面的 geomvals 可以覆盖前面的 geomvals

Code

WITH foo AS (
    SELECT 1 AS rid, ST_AddBand(ST_MakeEmptyRaster(5, 5, 0, 0, 1, -1, 0, 0, 0), 1, '8BUI', 0, 0) AS rast
), bar AS (
    SELECT 1 AS gid, 'SRID=0;POINT(2.5 -2.5)'::geometry geom UNION ALL
    SELECT 2 AS gid, 'SRID=0;POLYGON((1 -1,4 -1,4 -4,1 -4,1 -1))'::geometry geom UNION ALL
    SELECT 3 AS gid, 'SRID=0;POLYGON((0 0,5 0,5 -1,1 -1,1 -4,0 -4,0 0))'::geometry geom UNION ALL
    SELECT 4 AS gid, 'SRID=0;MULTIPOINT(0 0,4 4,4 -4)'::geometry
), changed AS (
    SELECT ST_SetValues(
        rast,
        1,
        ARRAY[
            ROW((SELECT geom FROM bar WHERE gid = 1), 1),
            ROW((SELECT geom FROM bar WHERE gid = 2), 2)
        ]::geomval[]
    ) AS rast
    FROM foo
)
SELECT
    y,
    array_agg(ST_Value(rast, 1, x, y) ORDER BY x) AS values
FROM changed
CROSS JOIN generate_series(1, 5) AS x
CROSS JOIN generate_series(1, 5) AS y
GROUP BY y
ORDER BY y;

栅格输出

y |           values
---+----------------------------
 1 | {NULL,NULL,NULL,NULL,NULL}
 2 | {NULL,2,2,2,NULL}
 3 | {NULL,2,2,2,NULL}
 4 | {NULL,2,2,2,NULL}
 5 | {NULL,NULL,NULL,NULL,NULL}
(5 rows)

这个例子与前面的例子相反

Code

WITH foo AS (
    SELECT 1 AS rid, ST_AddBand(ST_MakeEmptyRaster(5, 5, 0, 0, 1, -1, 0, 0, 0), 1, '8BUI', 0, 0) AS rast
), bar AS (
    SELECT 1 AS gid, 'SRID=0;POINT(2.5 -2.5)'::geometry geom UNION ALL
    SELECT 2 AS gid, 'SRID=0;POLYGON((1 -1,4 -1,4 -4,1 -4,1 -1))'::geometry geom UNION ALL
    SELECT 3 AS gid, 'SRID=0;POLYGON((0 0,5 0,5 -1,1 -1,1 -4,0 -4,0 0))'::geometry geom UNION ALL
    SELECT 4 AS gid, 'SRID=0;MULTIPOINT(0 0,4 4,4 -4)'::geometry
), changed AS (
    SELECT ST_SetValues(
        rast,
        1,
        ARRAY[
            ROW((SELECT geom FROM bar WHERE gid = 2), 2),
            ROW((SELECT geom FROM bar WHERE gid = 1), 1)
        ]::geomval[]
    ) AS rast
    FROM foo
)
SELECT
    y,
    array_agg(ST_Value(rast, 1, x, y) ORDER BY x) AS values
FROM changed
CROSS JOIN generate_series(1, 5) AS x
CROSS JOIN generate_series(1, 5) AS y
GROUP BY y
ORDER BY y;

栅格输出

y |           values
---+----------------------------
 1 | {NULL,NULL,NULL,NULL,NULL}
 2 | {NULL,2,2,2,NULL}
 3 | {NULL,2,1,2,NULL}
 4 | {NULL,2,2,2,NULL}
 5 | {NULL,NULL,NULL,NULL,NULL}
(5 rows)

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名称

大纲

Description

示例

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