WXP::Calc Class Reference
[Compute objects]

This class contains functions for doing simple meteorological computations. More...

#include "../include/Calc.h"

Static Public Member Functions
static float	windSpd (float u, float v)
static float	windDir (float u, float v)
static float	windU (float dir, float spd)
static float	windV (float dir, float spd)
static float	vaporPres (float t)
static float	windChillTemp (float temp, float ws)
static float	windChillTemp2 (float temp, float ws)
static float	windChill (float temp, float ws)
static float	heatIndex (float temp, float dewp)
static float	humiture (float temp, float dewp)
static float	tempHumIndex (float temp, float dewp)
static float	sfcPrAlt (float alt, float el)
static float	presAlt (float pres)
static float	mixRatio (float temp, float pr)
static float	specHum (float temp, float pr)
static float	dewTemp (float temp, float rh)
static float	potTemp (float temp, float pr)
static float	virtTemp (float temp, float dewp, float pr)
static float	virtPotTemp (float temp, float dewp, float pr)
static float	tempOnSatAd (float pot, float pr)
static float	tempOnDryAd (float pot, float pr)
static float	thetaeOnSatAd (float temp, float pr)
static float	tempVaporPres (float e)
static float	tempOnMixRat (float w, float pr)
static float	relHum (float t, float td)
static float	convTemp (float wbar, float pc, float pr)
static float	lclPres (float ts, float tds, float ps)
static float	lclTemp (float ts, float ps, float plcl)
static int	lcl (float ts, float tds, float ps, LclData &ldat)
static LclData	lcl (float ts, float tds, float ps)
static float	eqPotTemp (float temp, float dewp, float pr)
static float	wetBulb (float temp, float dewp, float pr)
static float	wetBulbPotTemp (float temp, float dewp, float pr)
static float	interpLinear (float x, float x1, float x2, float y1, float y2)
static float	interpTemp (float t1, float t2, float p1, float p2, float pr)
static float	earthDist (float lat1, float lon1, float lat2, float lon2)
static float	earthAngle (float lat1, float lon1, float lat2, float lon2)
static float	dist (float x1, float y1, float x2, float y2)
static float	Min (float x, float y)
static float	Max (float x, float y)
static float	ADD (float x, float y)
static float	DIF (float x, float y)
static float	MUL (float x, float y)
static float	DIV (float x, float y)

Detailed Description

This class contains functions for doing simple meteorological computations.

Author:: Dan Vietor

Member Function Documentation

static float WXP::Calc::ADD	(	float	x,
		float	y
	)			`[inline, static]`

Add two values and check for missing

References WXP::Const::MISS.

Referenced by WXP::MosUFile::decodeETA().

float Calc::convTemp	(	float	wbar,
		float	pc,
		float	pr
	)			`[static]`

Convective temperature in Kelvin

Parameters:

	wbar	Mean mixing ratio in gm/kg from prCcl
	pc	Pressure in mb at the CCL from prCcl
	pr	Surface pressure in millibars

References potTemp(), tempOnDryAd(), and tempOnMixRat().

float Calc::dewTemp	(	float	temp,
		float	rh
	)			`[static]`

Dewpoint temperature in Kelvin

Parameters:

	temp	Temperature in Kelvin
	rh	Relative humidity in %

References WXP::Const::MISS, tempVaporPres(), and vaporPres().

Referenced by WXP::SynopTool::decode().

static float WXP::Calc::DIF	(	float	x,
		float	y
	)			`[inline, static]`

Difference two values and check for missing

References WXP::Const::MISS.

Referenced by WXP::SfcDataTool::compute(), and WXP::MosDataTool::compute().

static float WXP::Calc::DIV	(	float	x,
		float	y
	)			`[inline, static]`

Divide two values and check for missing

References WXP::Const::MISS.

Referenced by WXP::SfcDataTool::compute().

float Calc::earthAngle	(	float	lat1,
		float	lon1,
		float	lat2,
		float	lon2
	)			`[static]`

Compute the spherical angle between two points in degrees

Parameters:

	lat1	Latitude of first point
	lon1	Longitude of first point
	lat2	Latitude of second point
	lon2	Longitude of second point

References WXP::Const::DRC, WXP::Const::MISS, and WXP::Const::RDC.

Referenced by earthDist().

float Calc::earthDist	(	float	lat1,
		float	lon1,
		float	lat2,
		float	lon2
	)			`[static]`

Compute the spherical distance between two points in meters

Parameters:

	lat1	Latitude of first point
	lon1	Longitude of first point
	lat2	Latitude of second point
	lon2	Longitude of second point

References WXP::Const::DRC, WXP::Const::EARTH, and earthAngle().

Referenced by WXP::Domain::calcEarthDist().

float Calc::eqPotTemp	(	float	temp,
		float	dewp,
		float	pr
	)			`[static]`

Equivalent potential temperature in Kelvin

Parameters:

	temp	Temperature in Kelvin
	dewp	Dewpoint in Kelvin
	pr	Pressure in millibars

References lclPres(), lclTemp(), WXP::Const::MISS, potTemp(), and thetaeOnSatAd().

Referenced by WXP::SfcDataTool::compute().

float Calc::heatIndex	(	float	temp,
		float	dewp
	)			`[static]`

Heat index in Kelvin Source: NWS Southern Region SSD Technical Attachment 8/12/86. Heat Index was originally known as the apparent temperature index. JAM - July, 1979.

Parameters:

	temp	Temperature in Kelvin
	dewp	Dewpoint in Kelvin

References WXP::Convert::FtoK(), WXP::Convert::KtoF(), WXP::Const::MISS, and vaporPres().

Referenced by WXP::SfcDataTool::compute(), and WXP::MosDataTool::compute().

float Calc::humiture	(	float	temp,
		float	dewp
	)			`[static]`

Humiture in Fahrenheit

Parameters:

	temp	Temperature in Kelvin
	dewp	Dewpoint in Kelvin

References WXP::Convert::KtoF(), WXP::Const::MISS, and vaporPres().

Referenced by WXP::SfcDataTool::compute(), and WXP::MosDataTool::compute().

float Calc::interpLinear	(	float	x,
		float	x1,
		float	x2,
		float	y1,
		float	y2
	)			`[static]`

Interpolates between two values

Parameters:

	x	X value to interpolate to
	x1	First X
	x2	Second X
	y1	First Y
	y2	Second Y

Returns:: Y value corresponding to X

float Calc::interpTemp	(	float	t1,
		float	t2,
		float	p1,
		float	p2,
		float	pr
	)			`[static]`

Temperature interpolated between two pressure levels in Kelvin

Parameters:

	t1	Temperature in K at bottom of the layer
	t2	Temperature in K at top of the layer
	p1	Pressure in mb at bottom of the layer
	p2	Pressure in mb at top of the layer
	pr	Pressure in mb at level of interest

References WXP::Const::MISS.

LclData Calc::lcl	(	float	ts,
		float	tds,
		float	ps
	)			`[static]`

Compute LCL parameters

Parameters:

	ts	Temperature in K at the surface
	tds	Dewpoint temperature in K at the surface
	ps	Pressure in mb at the surface

Returns:: LCL parameters (p in mb,t in K)

References lcl().

int Calc::lcl	(	float	ts,
		float	tds,
		float	ps,
		LclData &	ldat
	)			`[static]`

Compute LCL parameters

Parameters:

	ts	Temperature in K at the surface
	tds	Dewpoint temperature in K at the surface
	ps	Pressure in mb at the surface

Return values:

ldat

LCL parameters (p in mb,t in K)

References WXP::Const::MISS, mixRatio(), potTemp(), tempOnDryAd(), and tempOnMixRat().

Referenced by lcl(), and lclPres().

float Calc::lclPres	(	float	ts,
		float	tds,
		float	ps
	)			`[static]`

Pressure at the LCL in millibars

Parameters:

	ts	Temperature in K at the surface
	tds	Dewpoint temperature in K at the surface
	ps	Pressure in mb at the surface

References lcl().

Referenced by WXP::SfcDataTool::compute(), eqPotTemp(), wetBulb(), and wetBulbPotTemp().

float Calc::lclTemp	(	float	ts,
		float	ps,
		float	plcl
	)			`[static]`

Temperature at the LCL in K

Parameters:

	ts	Temperature in K at the surface
	ps	Pressure in mb at the surface
	plcl	Pressure at the LCL (from lclPres)

References potTemp(), and tempOnDryAd().

Referenced by eqPotTemp(), wetBulb(), and wetBulbPotTemp().

static float WXP::Calc::Max	(	float	x,
		float	y
	)			`[inline, static]`

Maximum value of two values

static float WXP::Calc::Min	(	float	x,
		float	y
	)			`[inline, static]`

Minimum value of two values

float Calc::mixRatio	(	float	temp,
		float	pr
	)			`[static]`

Mixing ratio in gm/kg

Parameters:

	temp	Temperature in K or vapor pressure in mb
	pr	Pressure in millibars

References WXP::Const::MISS, and vaporPres().

Referenced by WXP::SfcDataTool::compute(), lcl(), tempOnSatAd(), thetaeOnSatAd(), and virtTemp().

static float WXP::Calc::MUL	(	float	x,
		float	y
	)			`[inline, static]`

Multiply two values and check for missing

References WXP::Const::MISS.

Referenced by WXP::MosUFile::decodeETA().

float Calc::potTemp	(	float	temp,
		float	pr
	)			`[static]`

Potential temperature in Kelvin

Parameters:

	temp	Temperature in Kelvin
	pr	Pressure in millibars

References WXP::Const::MISS.

Referenced by WXP::SfcDataTool::compute(), convTemp(), eqPotTemp(), lcl(), lclTemp(), WXP::Domain::pan(), tempOnSatAd(), WXP::Domain::tran(), virtPotTemp(), and WXP::Domain::zoom().

float Calc::presAlt ( float pres ) [static]

Pressure altitude in m given pressure in millibars

Parameters:

pres

Pressure in millibars

float Calc::relHum	(	float	t,
		float	td
	)			`[static]`

Relative humidity in percent

Parameters:

	t	Temperature in Kelvin or Celsius
	td	Dewpoint in Kelvin or Celsius

References WXP::Convert::CtoK(), WXP::Const::MISS, and vaporPres().

Referenced by WXP::SfcDataTool::compute(), WXP::MosDataTool::compute(), and WXP::SfcData::outString().

float Calc::sfcPrAlt	(	float	alt,
		float	el
	)			`[static]`

Surface pressure in mb given altimeter setting

Parameters:

	alt	Altimeter setting in millibars
	el	Elevation in meters

References WXP::Const::MISS.

Referenced by WXP::SfcDataTool::compute().

float Calc::specHum	(	float	temp,
		float	pr
	)			`[static]`

Specific humidity in gm/kg

Parameters:

	temp	Temperature in K or vapor pressure in mb
	pr	Pressure in millibars

References WXP::Const::MISS, and vaporPres().

Referenced by WXP::SfcDataTool::compute().

float Calc::tempHumIndex	(	float	temp,
		float	dewp
	)			`[static]`

Temperature humidity index in Fahrenheit

Parameters:

	temp	Temperature in Fahrenheit
	dewp	Dewpoint in Fahrenheit

References WXP::Const::MISS.

float Calc::tempOnDryAd	(	float	pot,
		float	pr
	)			`[static]`

Temperature on a dry adiabat in Kelvin

Parameters:

	pot	Potential temperature in Kelvin
	pr	Pressure in millibars

Referenced by convTemp(), lcl(), and lclTemp().

float Calc::tempOnMixRat	(	float	w,
		float	pr
	)			`[static]`

Temperature on a mixing ratio line

Parameters:

	w	Mixing ratio in gm/kg
	pr	Pressure in millibars

Referenced by convTemp(), and lcl().

float Calc::tempOnSatAd	(	float	pot,
		float	pr
	)			`[static]`

Temperature on a saturation adiabat in Kelvin

Parameters:

	pot	Equivalent potential temperature in K
	pr	Pressure in mb

References WXP::Const::MISS, mixRatio(), and potTemp().

Referenced by wetBulb(), and wetBulbPotTemp().

float Calc::tempVaporPres ( float e ) [static]

Temperature in Kelvin given a specific vapor pressure

Parameters:

e

Vapor pressure in millibars

Referenced by dewTemp().

float Calc::thetaeOnSatAd	(	float	temp,
		float	pr
	)			`[static]`

Equivalent potential temperature on a saturation adiabat in Kelvin

Parameters:

	temp	Temperature in Kelvin
	pr	Pressure in millibars

References mixRatio().

Referenced by eqPotTemp(), wetBulb(), and wetBulbPotTemp().

float Calc::vaporPres ( float t ) [static]

Saturation vapor pressure in millibars

Parameters:

t

Temperature in Kelvin

References WXP::Const::MISS.

Referenced by WXP::SfcDataTool::compute(), WXP::MosDataTool::compute(), dewTemp(), heatIndex(), humiture(), mixRatio(), relHum(), and specHum().

float Calc::virtPotTemp	(	float	temp,
		float	dewp,
		float	pr
	)			`[static]`

Virtual potential temperature in Kelvin

Parameters:

	temp	Temperature in Kelvin
	dewp	Dewpoint in Kelvin
	pr	Pressure in millibars

References WXP::Const::MISS, potTemp(), and virtTemp().

Referenced by WXP::SfcDataTool::compute().

float Calc::virtTemp	(	float	temp,
		float	dewp,
		float	pr
	)			`[static]`

Virtual temperature in Kelvin

Parameters:

	temp	Temperature in Kelvin
	dewp	Dewpoint in Kelvin or mixing ratio in gm/kg
	pr	Pressure in millibars

References WXP::Const::MISS, and mixRatio().

Referenced by WXP::SfcDataTool::compute(), and virtPotTemp().

float Calc::wetBulb	(	float	temp,
		float	dewp,
		float	pr
	)			`[static]`

Wet bulb temperature in Kelvin

Parameters:

	temp	Temperature in Kelvin
	dewp	Dewpoint in Kelvin
	pr	Pressure in millibars

References lclPres(), lclTemp(), WXP::Const::MISS, tempOnSatAd(), and thetaeOnSatAd().

Referenced by WXP::SfcDataTool::compute().

float Calc::wetBulbPotTemp	(	float	temp,
		float	dewp,
		float	pr
	)			`[static]`

Wet bulb potential temperature in Kelvin

Parameters:

	temp	Temperature in Kelvin
	dewp	Dewpoint in Kelvin
	pr	Pressure in millibars

References lclPres(), lclTemp(), WXP::Const::MISS, tempOnSatAd(), and thetaeOnSatAd().

Referenced by WXP::SfcDataTool::compute().

float Calc::windChill	(	float	temp,
		float	ws
	)			`[static]`

Wind chill in Watts per square meter

Parameters:

	temp	Temperature in Kelvin
	ws	Wind speed in meters per second

References WXP::Const::MISS.

Referenced by WXP::SfcDataTool::compute(), and WXP::MosDataTool::compute().

float Calc::windChillTemp	(	float	temp,
		float	ws
	)			`[static]`

Wind chill in Kelvin

Parameters:

	temp	Temperature in Kelvin
	ws	Wind speed in meters per second

References WXP::Const::MISS.

Referenced by WXP::SfcDataTool::compute(), and WXP::MosDataTool::compute().

float Calc::windChillTemp2	(	float	temp,
		float	ws
	)			`[static]`

Wind chill (new version) in Kelvin

Parameters:

	temp	Temperature in Kelvin
	ws	Wind speed in meters per second

References WXP::Const::MISS.

Referenced by WXP::SfcDataTool::compute(), and WXP::MosDataTool::compute().

float Calc::windDir	(	float	u,
		float	v
	)			`[static]`

Wind direction computed from U,V components

Parameters:

	u	U wind component
	v	V wind component

References WXP::Const::MISS, and WXP::Const::RDC.

Referenced by WXP::GridMath::adjustUV().

float Calc::windSpd	(	float	u,
		float	v
	)			`[static]`

Wind speed computed from U,V components

Parameters:

	u	U wind component
	v	V wind component

References WXP::Const::MISS.

Referenced by WXP::GridMath::adjustUV().

float Calc::windU	(	float	dir,
		float	spd
	)			`[static]`

U wind component computed from direction and speed

Parameters:

	dir	Wind direction
	spd	Wind speed

References WXP::Const::DRC, and WXP::Const::MISS.

Referenced by WXP::GridMath::adjustUV().

float Calc::windV	(	float	dir,
		float	spd
	)			`[static]`

V wind component computed from direction and speed

Parameters:

	dir	Wind direction
	spd	Wind speed

References WXP::Const::DRC, and WXP::Const::MISS.

Referenced by WXP::GridMath::adjustUV().

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

Calc.h
Calc.cc

WXP::Calc Class Reference [Compute objects]

Static Public Member Functions

Detailed Description

Member Function Documentation

WXP::Calc Class Reference
[Compute objects]