---
name: v.select
description: "Selects features from vector map (A) by features from other vector map (B)."
keywords: [ vector, geometry, spatial query ]
---

# v.select

Selects features from vector map (A) by features from other vector map (B).

=== "Command line"

    **v.select**
    [**-tcr**]
    **ainput**=*name*
    [**alayer**=*string*]
    [**atype**=*string* [,*string*,...]]
    **binput**=*name*
    [**blayer**=*string*]
    [**btype**=*string* [,*string*,...]]
    **output**=*name*
    **operator**=*string*
    [**relate**=*string*]
    [**--overwrite**]
    [**--verbose**]
    [**--quiet**]
    [**--qq**]
    [**--ui**]

    Example:

    ```sh
    v.select ainput=name binput=name output=name operator=overlap
    ```

=== "Python (grass.tools)"

    *grass.tools.Tools.v_select*(**ainput**,
        **alayer**=*"1"*,
        **atype**=*"point,line,area"*,
        **binput**,
        **blayer**=*"1"*,
        **btype**=*"point,line,area"*,
        **output**,
        **operator**=*"overlap"*,
        **relate**=*None*,
        **flags**=*None*,
        **overwrite**=*None*,
        **verbose**=*None*,
        **quiet**=*None*,
        **superquiet**=*None*)

    Example:

    ```python
    tools = Tools()
    tools.v_select(ainput="name", binput="name", output="name", operator="overlap")
    ```

    This grass.tools API is experimental in version 8.5 and expected to be stable in version 8.6.

=== "Python (grass.script)"

    *grass.script.run_command*("***v.select***",
        **ainput**,
        **alayer**=*"1"*,
        **atype**=*"point,line,area"*,
        **binput**,
        **blayer**=*"1"*,
        **btype**=*"point,line,area"*,
        **output**,
        **operator**=*"overlap"*,
        **relate**=*None*,
        **flags**=*None*,
        **overwrite**=*None*,
        **verbose**=*None*,
        **quiet**=*None*,
        **superquiet**=*None*)

    Example:

    ```python
    gs.run_command("v.select", ainput="name", binput="name", output="name", operator="overlap")
    ```

## Parameters

=== "Command line"

    **ainput**=*name* **[required]**  
    &nbsp;&nbsp;&nbsp;&nbsp;Name of input vector map  
    &nbsp;&nbsp;&nbsp;&nbsp;Input vector map from which to select features (A)  
    **alayer**=*string*  
    &nbsp;&nbsp;&nbsp;&nbsp;Layer number (vector map A)  
    &nbsp;&nbsp;&nbsp;&nbsp;Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *1*  
    **atype**=*string* [,*string*,...]  
    &nbsp;&nbsp;&nbsp;&nbsp;Feature type (vector map A)  
    &nbsp;&nbsp;&nbsp;&nbsp;Input feature type  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *point, line, boundary, centroid, area*  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *point,line,area*  
    **binput**=*name* **[required]**  
    &nbsp;&nbsp;&nbsp;&nbsp;Name of input vector map  
    &nbsp;&nbsp;&nbsp;&nbsp;Query vector map (B)  
    **blayer**=*string*  
    &nbsp;&nbsp;&nbsp;&nbsp;Layer number (vector map B)  
    &nbsp;&nbsp;&nbsp;&nbsp;Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *1*  
    **btype**=*string* [,*string*,...]  
    &nbsp;&nbsp;&nbsp;&nbsp;Feature type (vector map B)  
    &nbsp;&nbsp;&nbsp;&nbsp;Input feature type  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *point, line, boundary, centroid, area*  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *point,line,area*  
    **output**=*name* **[required]**  
    &nbsp;&nbsp;&nbsp;&nbsp;Name for output vector map  
    **operator**=*string* **[required]**  
    &nbsp;&nbsp;&nbsp;&nbsp;Operator defines required relation between features  
    &nbsp;&nbsp;&nbsp;&nbsp;A feature is written to output if the result of operation 'ainput operator binput' is true. An input feature is considered to be true, if category of given layer is defined.  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *overlap, equals, disjoint, intersects, touches, crosses, within, contains, overlaps, relate*  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *overlap*  
    &nbsp;&nbsp;&nbsp;&nbsp;**overlap**: features partially or completely overlap  
    &nbsp;&nbsp;&nbsp;&nbsp;**equals**: features are spatially equals (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**disjoint**: features do not spatially intersect (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**intersects**: features spatially intersect (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**touches**: features spatially touches (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**crosses**: features spatially crosses (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**within**: feature A is completely inside feature B (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**contains**: feature B is completely inside feature A (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**overlaps**: features spatially overlap (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**relate**: feature A is spatially related to feature B (using GEOS, requires 'relate' option)  
    **relate**=*string*  
    &nbsp;&nbsp;&nbsp;&nbsp;Intersection Matrix Pattern used for 'relate' operator  
    **-t**  
    &nbsp;&nbsp;&nbsp;&nbsp;Do not create attribute table  
    **-c**  
    &nbsp;&nbsp;&nbsp;&nbsp;Do not skip features without category  
    **-r**  
    &nbsp;&nbsp;&nbsp;&nbsp;Reverse selection  
    **--overwrite**  
    &nbsp;&nbsp;&nbsp;&nbsp;Allow output files to overwrite existing files  
    **--help**  
    &nbsp;&nbsp;&nbsp;&nbsp;Print usage summary  
    **--verbose**  
    &nbsp;&nbsp;&nbsp;&nbsp;Verbose module output  
    **--quiet**  
    &nbsp;&nbsp;&nbsp;&nbsp;Quiet module output  
    **--qq**  
    &nbsp;&nbsp;&nbsp;&nbsp;Very quiet module output  
    **--ui**  
    &nbsp;&nbsp;&nbsp;&nbsp;Force launching GUI dialog

=== "Python (grass.tools)"

    **ainput** : str, *required*  
    &nbsp;&nbsp;&nbsp;&nbsp;Name of input vector map  
    &nbsp;&nbsp;&nbsp;&nbsp;Input vector map from which to select features (A)  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: input, vector, *name*  
    **alayer** : str, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Layer number (vector map A)  
    &nbsp;&nbsp;&nbsp;&nbsp;Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: input, layer  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *1*  
    **atype** : str | list[str], *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Feature type (vector map A)  
    &nbsp;&nbsp;&nbsp;&nbsp;Input feature type  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *point, line, boundary, centroid, area*  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *point,line,area*  
    **binput** : str, *required*  
    &nbsp;&nbsp;&nbsp;&nbsp;Name of input vector map  
    &nbsp;&nbsp;&nbsp;&nbsp;Query vector map (B)  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: input, vector, *name*  
    **blayer** : str, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Layer number (vector map B)  
    &nbsp;&nbsp;&nbsp;&nbsp;Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: input, layer  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *1*  
    **btype** : str | list[str], *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Feature type (vector map B)  
    &nbsp;&nbsp;&nbsp;&nbsp;Input feature type  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *point, line, boundary, centroid, area*  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *point,line,area*  
    **output** : str, *required*  
    &nbsp;&nbsp;&nbsp;&nbsp;Name for output vector map  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: output, vector, *name*  
    **operator** : str, *required*  
    &nbsp;&nbsp;&nbsp;&nbsp;Operator defines required relation between features  
    &nbsp;&nbsp;&nbsp;&nbsp;A feature is written to output if the result of operation 'ainput operator binput' is true. An input feature is considered to be true, if category of given layer is defined.  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *overlap, equals, disjoint, intersects, touches, crosses, within, contains, overlaps, relate*  
    &nbsp;&nbsp;&nbsp;&nbsp;**overlap**: features partially or completely overlap  
    &nbsp;&nbsp;&nbsp;&nbsp;**equals**: features are spatially equals (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**disjoint**: features do not spatially intersect (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**intersects**: features spatially intersect (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**touches**: features spatially touches (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**crosses**: features spatially crosses (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**within**: feature A is completely inside feature B (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**contains**: feature B is completely inside feature A (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**overlaps**: features spatially overlap (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**relate**: feature A is spatially related to feature B (using GEOS, requires 'relate' option)  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *overlap*  
    **relate** : str, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Intersection Matrix Pattern used for 'relate' operator  
    **flags** : str, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *t*, *c*, *r*  
    &nbsp;&nbsp;&nbsp;&nbsp;**t**  
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Do not create attribute table  
    &nbsp;&nbsp;&nbsp;&nbsp;**c**  
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Do not skip features without category  
    &nbsp;&nbsp;&nbsp;&nbsp;**r**  
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Reverse selection  
    **overwrite** : bool, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Allow output files to overwrite existing files  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *None*  
    **verbose** : bool, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Verbose module output  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *None*  
    **quiet** : bool, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Quiet module output  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *None*  
    **superquiet** : bool, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Very quiet module output  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *None*  

    Returns:

    **result** : grass.tools.support.ToolResult | None  
    If the tool produces text as standard output, a *ToolResult* object will be returned. Otherwise, `None` will be returned.

    Raises:

    *grass.tools.ToolError*: When the tool ended with an error.

=== "Python (grass.script)"

    **ainput** : str, *required*  
    &nbsp;&nbsp;&nbsp;&nbsp;Name of input vector map  
    &nbsp;&nbsp;&nbsp;&nbsp;Input vector map from which to select features (A)  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: input, vector, *name*  
    **alayer** : str, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Layer number (vector map A)  
    &nbsp;&nbsp;&nbsp;&nbsp;Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: input, layer  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *1*  
    **atype** : str | list[str], *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Feature type (vector map A)  
    &nbsp;&nbsp;&nbsp;&nbsp;Input feature type  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *point, line, boundary, centroid, area*  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *point,line,area*  
    **binput** : str, *required*  
    &nbsp;&nbsp;&nbsp;&nbsp;Name of input vector map  
    &nbsp;&nbsp;&nbsp;&nbsp;Query vector map (B)  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: input, vector, *name*  
    **blayer** : str, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Layer number (vector map B)  
    &nbsp;&nbsp;&nbsp;&nbsp;Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: input, layer  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *1*  
    **btype** : str | list[str], *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Feature type (vector map B)  
    &nbsp;&nbsp;&nbsp;&nbsp;Input feature type  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *point, line, boundary, centroid, area*  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *point,line,area*  
    **output** : str, *required*  
    &nbsp;&nbsp;&nbsp;&nbsp;Name for output vector map  
    &nbsp;&nbsp;&nbsp;&nbsp;Used as: output, vector, *name*  
    **operator** : str, *required*  
    &nbsp;&nbsp;&nbsp;&nbsp;Operator defines required relation between features  
    &nbsp;&nbsp;&nbsp;&nbsp;A feature is written to output if the result of operation 'ainput operator binput' is true. An input feature is considered to be true, if category of given layer is defined.  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *overlap, equals, disjoint, intersects, touches, crosses, within, contains, overlaps, relate*  
    &nbsp;&nbsp;&nbsp;&nbsp;**overlap**: features partially or completely overlap  
    &nbsp;&nbsp;&nbsp;&nbsp;**equals**: features are spatially equals (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**disjoint**: features do not spatially intersect (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**intersects**: features spatially intersect (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**touches**: features spatially touches (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**crosses**: features spatially crosses (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**within**: feature A is completely inside feature B (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**contains**: feature B is completely inside feature A (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**overlaps**: features spatially overlap (using GEOS)  
    &nbsp;&nbsp;&nbsp;&nbsp;**relate**: feature A is spatially related to feature B (using GEOS, requires 'relate' option)  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *overlap*  
    **relate** : str, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Intersection Matrix Pattern used for 'relate' operator  
    **flags** : str, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Allowed values: *t*, *c*, *r*  
    &nbsp;&nbsp;&nbsp;&nbsp;**t**  
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Do not create attribute table  
    &nbsp;&nbsp;&nbsp;&nbsp;**c**  
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Do not skip features without category  
    &nbsp;&nbsp;&nbsp;&nbsp;**r**  
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Reverse selection  
    **overwrite** : bool, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Allow output files to overwrite existing files  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *None*  
    **verbose** : bool, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Verbose module output  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *None*  
    **quiet** : bool, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Quiet module output  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *None*  
    **superquiet** : bool, *optional*  
    &nbsp;&nbsp;&nbsp;&nbsp;Very quiet module output  
    &nbsp;&nbsp;&nbsp;&nbsp;Default: *None*

## DESCRIPTION

*v.select* allows the user to select features from a vector map by
features from another one.

Supported operators (without GEOS; using GRASS' own algorithm):

- **overlap** - features partially or completely overlap (GEOS
  equivalent: intersects)

Supported operators (internally using
[GEOS](https://trac.osgeo.org/geos/) - Geometry Engine, Open Source):

- **equals** - features are spatially equals
- **disjoint** - features do not spatially intersect
- **intersects** - features spatially intersect (equivalent to native
  'overlap')
- **touches** - features spatially touches
- **crosses** - features spatially crosses
- **within** - feature A is completely inside feature B
- **contains** - feature B is completely inside feature A
- **overlaps** - features spatially overlap
- **relate** - feature A is spatially related to feature B

## NOTES

Only features with category numbers will be considered. If required the
*[v.category](v.category.md)* module can be used to add them. Typically
boundaries do not need to be given a category number, as an area's
attributes are inherited from the centroid. Typically points, lines, and
centroids will always want to have a cat number. E.g. take a road which
separates two farms. It is ambiguous as to which farm an attribute that
is attached to the road belongs to. The boundary only needs a cat number
if it will hold its own attributes, such as road name or pavement form.
A centroid in each paddock holds the information with respect to
ownership, area, etc.

## EXAMPLES

Preparation of example data (North Carolina sample dataset):

```sh
# Create an grid for overlaying to ZIP code vector map
v.mkgrid map=boxgrid grid=10,10 position=coor \
         coordinates=583600,201500 box=5000,5000

# set region to ZIP codes and boxgrid vector maps
g.region vector=zipcodes_wake,boxgrid -p res=100 -a
# enlarge region a bit for "white border" around map in monitor
g.region n=n+1000 s=s-1000 w=w-1000 e=e+1000 -p
d.mon wx0
```

### OVERLAP: features partially or completely overlap (using GRASS)

Select grid boxes (North Carolina sample dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=boxgrid fill_color=85:130:176
v.select ainput=boxgrid binput=zipcodes_wake output=v_select_OVERLAP operator=overlap
d.vect map=v_select_OVERLAP
d.vect map=zipcodes_wake type=boundary color=255:255:50
```

![v.select with OVERLAP operator](v_select_op_overlap.png)  
v.select with OVERLAP operator: selected grid boxes shown in yellow
(using GRASS method)

### OVERLAPS features spatially overlap (using GEOS)

Select grid boxes (North Carolina sample dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=boxgrid fill_color=85:130:176
v.select ainput=boxgrid binput=zipcodes_wake output=v_select_OVERLAPS operator=overlaps
d.vect map=v_select_OVERLAPS
d.vect map=zipcodes_wake type=boundary color=255:255:50
```

![v.select with OVERLAPS operator](v_select_op_overlaps.png)  
v.select with OVERLAPS operator: selected grid boxes shown in yellow
(using GEOS method)

### DISJOINT: features do not spatially intersect (using GEOS)

Select grid boxes (North Carolina sample dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=boxgrid fill_color=85:130:176
v.select ainput=boxgrid binput=zipcodes_wake output=v_select_DISJOINT operator=disjoint
d.vect map=v_select_DISJOINT
d.vect map=zipcodes_wake type=boundary color=255:255:50
```

![v.select with DISJOINT operator](v_select_op_disjoint.png)  
v.select with DISJOINT operator: selected grid boxes shown in yellow

### EQUALS: features are spatially equals (using GEOS)

Select zipcode polygon (North Carolina sample dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
v.extract input=zipcodes_wake where=ZIPCODE_ID=35 output=zipcodeID35
v.select ainput=zipcodes_wake binput=zipcodeID35 output=v_select_EQUALS operator=equals
d.vect map=v_select_EQUALS
d.vect map=zipcodes_wake type=boundary color=255:255:50
```

![v.select with EQUALS operator](v_select_op_equals.png)  
v.select with EQUALS operator: selected grid boxes shown in yellow

### INTERSECTS: features spatially intersect (using GEOS)

Select zipcode polygons (North Carolina sample dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=boxgrid fill_color=85:130:176
v.select ainput=zipcodes_wake binput=boxgrid output=v_select_INTERSECTS operator=intersects
d.vect map=v_select_INTERSECTS
d.vect map=boxgrid type=boundary color=255:255:50
```

![v.select with INTERSECTS operator](v_select_op_intersects.png)  
v.select with INTERSECTS operator: selected grid boxes shown in yellow

### TOUCHES: features spatially touches (using GEOS)

Select polygons (North Carolina sample dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=zipcodeID35 fill_color=85:130:176
v.select ainput=zipcodes_wake binput=zipcodeID35 output=v_select_TOUCHES operator=touches
d.vect map=v_select_TOUCHES
d.vect map=zipcodes_wake type=boundary color=255:255:50
```

![v.select with TOUCHES operator](v_select_op_touches.png)  
v.select with TOUCHES operator: selected polygons shown in yellow (blue:
input polygon)

### CROSSES: features spatially crosses (using GEOS)

Select zipcode polygons by lines (North Carolina sample dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=busroute1 color=200:27:27 width=3
v.select ainput=zipcodes_wake binput=busroute1 output=v_select_CROSSES operator=crosses
d.vect map=v_select_CROSSES
d.vect map=zipcodes_wake type=boundary color=255:255:50
d.vect map=busroute1 color=200:27:27 width=3
```

![v.select with CROSSES operator](v_select_op_crosses.png)  
v.select with CROSSES operator: selected polygons shown in yellow (red:
input lines)

### WITHIN feature A is completely inside feature B (using GEOS)

Select zipcode polygons (North Carolina sample dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=boundary_county fill_color=85:130:176
v.select ainput=zipcodes_wake binput=boundary_county output=v_select_WITHIN operator=within
d.vect map=v_select_WITHIN
```

![v.select with WITHIN operator](v_select_op_within.png)  
v.select with WITHIN operator: selected polygons shown in yellow (blue:
input polygons)

### CONTAINS feature B is completely inside feature A (using GEOS)

Select zipcode polygon (North Carolina sample dataset):

#### CONTAINS with polygons

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=zipcodeID35 fill_color=85:130:176
v.select ainput=zipcodes_wake binput=zipcodeID35 \
         output=v_select_CONTAINS_pol operator=contains
d.vect map=v_select_CONTAINS
```

![v.select with CONTAINS operator](v_select_op_contains_pol.png)  
v.select with CONTAINS operator: selected polygon shown in yellow (blue:
input polygon, not visible)

#### CONTAINS with points

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=hospitals fill_color=195:31:31 icon=basic/cross3 size=10
v.select ainput=zipcodes_wake binput=hospitals \
         output=v_select_CONTAINS_pnts operator=contains
d.vect map=v_select_CONTAINS_pnts
d.vect map=hospitals fill_color=195:31:31 icon=basic/cross3 size=10
```

![v.select with CONTAINS operator](v_select_op_contains_pnts.png)  
v.select with CONTAINS operator: selected polygons shown in yellow (red:
input points)

### RELATE feature A is spatially related to feature B (using GEOS)

This operator additionally requires the **relate** parameter (in other
GIS called 'ST_Relate'). This operator allows calculating the
[Dimensionally Extended nine-Intersection Model
(DE-9IM)](https://en.wikipedia.org/wiki/DE-9IM). In the following one
example: Select polygon with 'TOUCHES' operator (North Carolina sample
dataset):

```sh
d.vect map=zipcodes_wake fill_color=0:128:0
d.vect map=zipcodeID35 fill_color=85:130:176
v.select ainput=zipcodeID35 binput=zipcodes_wake \
         output=v_select_TOUCHES_relate operator=relate relate='T********'
d.vect map=v_select_TOUCHES
```

The result of `relate='T********'` is the same as seen above in the
example 'TOUCHES'. See the
[DE-9IM](https://en.wikipedia.org/wiki/DE-9IM) page for related
operators and their definition.

### Extraction of points falling into a polygon

Extract fire stations (points) falling into urban area (polygon) - North
Carolina data set (point in polygon test):

```sh
v.select ainput=firestations binput=urbanarea output=urban_firestations \
         operator=overlap
```

### Extraction of lines overlapping with a polygon

Extract railroad lines from zip code map overlapping with the urban area
(line in polygon test):

```sh
v.select ainput=railroads binput=urbanarea \
         output=railroads_in_urbanarea operator=overlap
```

### Extraction of areas overlapping with a line

Extract those areas from zip code map which overlap with railroads
(polygon on line test):

```sh
# first add a tiny buffer around railroad lines:
v.buffer input=railroads output=railroads_buf20m \
  distance=20

v.select ainput=zipcodes_wake binput=railroads_buf20m \
  output=zipcodes_wake_railroads operator=overlap
```

## SEE ALSO

*[v.category](v.category.md), [v.clip](v.clip.md),
[v.overlay](v.overlay.md), [v.extract](v.extract.md)*

[GRASS SQL interface](sql.md)  
[GEOS](https://trac.osgeo.org/geos/) - Geometry Engine, Open Source

## AUTHORS

Radim Blazek  
GEOS support by Martin Landa, Czech Technical University in Prague,
Czech Republic  
ZIP code examples by Carol X. Garzon-Lopez, Trento, Italy

## SOURCE CODE

Available at: [v.select source code](https://github.com/OSGeo/grass/tree/main/vector/v.select)
([history](https://github.com/OSGeo/grass/commits/main/vector/v.select))  
Latest change: Monday Feb 09 18:47:00 2026 in commit [fe51d38](https://github.com/OSGeo/grass/commit/fe51d3824fc8d5aa0e1ced4d9110214dc0192676)
