CFGridMapping: CF grid mapping object

In ncdfCF: Easy Access to NetCDF Files with CF Metadata Conventions

CF grid mapping object

Description

This class contains the details for a coordinate reference system, or grid mapping in CF terms, of a data variable.

When reporting the coordinate reference system to the caller, a character string in WKT2 format is returned, following the OGC standard.

Super class

ncdfCF::CFObject -> CFGridMapping

Active bindings

friendlyClassName

(read-only) A nice description of the class.

Methods

Public methods

• CFGridMapping$new()

• CFGridMapping$print()

• CFGridMapping$brief()

• CFGridMapping$wkt2()

• CFGridMapping$write()

• CFGridMapping$clone()

Inherited methods

• ncdfCF::CFObject$append_attribute()
• ncdfCF::CFObject$attribute()
• ncdfCF::CFObject$delete_attribute()
• ncdfCF::CFObject$detach()
• ncdfCF::CFObject$dim()
• ncdfCF::CFObject$print_attributes()
• ncdfCF::CFObject$set_attribute()
• ncdfCF::CFObject$update_coordinates_attribute()
• ncdfCF::CFObject$write_attributes()

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Method new()

Create a new instance of this class.

Note that when a new grid mapping object is created (as opposed to reading from a netCDF resource), only the grid_mapping_name attribute will be set. The caller must set all other parameters through their respective attributes, following the CF Metadata Conventions.

Usage

CFGridMapping$new(var, grid_mapping_name)

Arguments

var

When creating a new grid mapping object, the name of the object. When reading from a netCDF resource, the netCDF variable that describes this instance.

grid_mapping_name

Optional. When creating a new grid mapping object, the formal name of the grid mapping, as specified in the CF Metadata Conventions. This value is stored in the new object as attribute "grid_mapping_name". Ignored when argument var is a NC object.

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Method print()

Prints a summary of the grid mapping to the console.

Usage

CFGridMapping$print()

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Method brief()

Retrieve a 1-row data.frame with some information on this grid mapping.

Usage

CFGridMapping$brief()

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Method wkt2()

Retrieve the CRS string for a specific variable.

Usage

CFGridMapping$wkt2(axis_info)

Arguments

axis_info

A list with information that describes the axes of the CFVariable instance to describe.

Returns

A character string with the CRS in WKT2 format.

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Method write()

Write the CRS object to a netCDF file.

Usage

CFGridMapping$write(h)

Arguments

h

Handle to the netCDF file opened for writing.

Returns

Self, invisibly.

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Method clone()

The objects of this class are cloneable with this method.

Usage

CFGridMapping$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

References

https://docs.ogc.org/is/18-010r11/18-010r11.pdf https://cfconventions.org/cf-conventions/cf-conventions.html#appendix-grid-mappings

ncdfCF documentation built on Sept. 13, 2025, 5:07 p.m.