NetcdfHandler Class Reference

#include <netcdf_handler.h>

Public Member Functions
void	readNCFile (const char *filename)
int	cacheCurrentField ()
void	closeNCFile ()
	Close the NetCDF file and release the file handle.
void	getDomainBounds (float *bounds)
int	getVar (char *name)
int	getCurrentSpeedAt (float x, float y, float z, float *value)
int	calculateDescriptorValues (float *values)
bool	isProfileFile ()

Detailed Description

Handler for reading NetCDF current field files.

Provides methods for opening NetCDF files, caching current velocity data, and looking it up at query positions. Two layouts are read, selected from the variable and dimension names found in the file:

• Grid (U_V_W_FILE): dimensions and coordinate variables zc, yc and xc, and velocity variables u, v and w on (zc, yc, xc).
• Profile (Z_PROFILE_FILE): no xc dimension; a zc dimension and coordinate variable, and u and v on (zc).

xc is NED north, yc NED east and zc depth, positive down; u, v and w are the north, east and down components. The cell size is taken from the first two coordinates of each axis, so the coordinates must be uniformly spaced. A position is given the value of the node at the lower corner of its cell, without interpolation.

Member Function Documentation

cacheCurrentField()

int NetcdfHandler::cacheCurrentField

(

)

Cache the entire current velocity field in memory.

Returns

0 on success, non-zero error code on failure.

calculateDescriptorValues()

int NetcdfHandler::calculateDescriptorValues

(

float *

values

)

Compute min, mean, and max velocity magnitude statistics.

Parameters

[out]

values

Array of at least 3 floats: [minVal, meanVal, maxVal] [m/s].

Returns

0 on success.

getCurrentSpeedAt()

int NetcdfHandler::getCurrentSpeedAt	(	float	x,
		float	y,
		float	z,
		float *	value
	)

Get interpolated current velocity at a position.

Parameters

[in]	x	X (xc, north) coordinate [m].
[in]	y	Y (yc, east) coordinate [m].
[in]	z	Z (zc, depth) coordinate [m].
[out]	value	Interpolated velocity components [u, v, w] [m/s].

Returns

0 on success.

getDomainBounds()

void NetcdfHandler::getDomainBounds

(

float *

bounds

)

Get the spatial domain bounds of the loaded field.

Parameters

[out]

bounds

Array of at least 6 floats [xmin, xmax, ymin, ymax, zmin, zmax] [m].

getVar()

int NetcdfHandler::getVar

(

char *

name

)

Get a NetCDF variable ID by name.

Parameters

[in]

name

Variable name string.

Returns

NetCDF variable ID, or a negative error code if not found.

isProfileFile()

bool NetcdfHandler::isProfileFile

(

)

Check whether the file is a depth-profile layout.

Returns

True if the file type is Z_PROFILE_FILE.

readNCFile()

void NetcdfHandler::readNCFile

(

const char *

filename

)

Open and parse a NetCDF file.

Parameters

[in]

filename

Path to NetCDF file.

Determines the file layout type from the variable and dimension names present in the file and loads the grid coordinate arrays.

Exceptions

std::runtime_error

If the file cannot be opened, is not one of the two layouts read, or has an axis of fewer than two coordinates.

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The documentation for this class was generated from the following file:

• webfhsim/reloadrepos/fhsim_environment/src/environment/util/netcdf_handler.h