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	equivPotTemp (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	stdAtmsPres (float height)

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

◆ ADD()

static float WXP::Calc::ADD	(	float	x,
		float	y
	)

inlinestatic

Add two values and check for missing

References WXP::Const::MISS.

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

◆ convTemp()

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().

◆ dewTemp()

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(), and WXP::RadMask::getSiteFilter().

◆ DIF()

static float WXP::Calc::DIF	(	float	x,
		float	y
	)

inlinestatic

Difference two values and check for missing

References WXP::Const::MISS.

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

◆ dist()

float Calc::dist	(	float	x1,
		float	y1,
		float	x2,
		float	y2
	)

static

Compute the distance between two points in plot units

Parameters

x1	X coordinate of first point
y1	Y coordinate of first point
x2	X coordinate of second point
y2	Y coordinate of second point

Returns: Distance

References WXP::Const::MISS.

Referenced by WXP::RcmDecode::decode(), and WXP::RcmDecode::filterOverlap().

◆ DIV()

static float WXP::Calc::DIV	(	float	x,
		float	y
	)

inlinestatic

Divide two values and check for missing

References WXP::Const::MISS.

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

◆ earthAngle()

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

Returns: Angle between points

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

Referenced by WXP::ImageMath::blank(), and earthDist().

◆ 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

Returns: Distance in meters

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

Referenced by WXP::Domain::calcEarthDist(), and WXP::CityTool::compareData().

◆ equivPotTemp()

float Calc::equivPotTemp	(	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::UpaCalc::calc(), and WXP::SfcDataTool::compute().

◆ heatIndex()

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

◆ humiture()

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

◆ interpLinear()

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

◆ interpTemp()

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

Returns: interpolated temperature

References WXP::Const::MISS.

◆ lcl() [1/2]

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().

◆ lcl() [2/2]

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(), WXP::LclData::p, potTemp(), WXP::LclData::t, tempOnDryAd(), and tempOnMixRat().

Referenced by WXP::ParcelParams::calc(), lcl(), and lclPres().

◆ 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(), and WXP::LclData::p.

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

◆ lclTemp()

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 equivPotTemp(), wetBulb(), and wetBulbPotTemp().

◆ Max()

static float WXP::Calc::Max	(	float	x,
		float	y
	)

inlinestatic

Maximum value of two values

◆ Min()

static float WXP::Calc::Min	(	float	x,
		float	y
	)

inlinestatic

Minimum value of two values

◆ mixRatio()

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::UpaCalc::calc(), WXP::SfcDataTool::compute(), lcl(), tempOnSatAd(), thetaeOnSatAd(), and virtTemp().

◆ MUL()

static float WXP::Calc::MUL	(	float	x,
		float	y
	)

inlinestatic

Multiply two values and check for missing

References WXP::Const::MISS.

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

◆ potTemp()

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::ParcelParams::calc(), WXP::UpaCalc::calc(), WXP::SfcDataTool::compute(), convTemp(), equivPotTemp(), lcl(), lclTemp(), tempOnSatAd(), WXP::Domain::tran(), WXP::Domain::tran(), and virtPotTemp().

◆ presAlt()

float Calc::presAlt ( float pres )

static

Pressure altitude in m given pressure in millibars

Parameters

pres	Pressure in millibars

◆ relHum()

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::UpaCalc::calc(), WXP::MosDataTool::compute(), WXP::SfcDataTool::compute(), and WXP::SfcData::outString().

◆ sfcPrAlt()

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().

◆ specHum()

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::UpaCalc::calc(), and WXP::SfcDataTool::compute().

◆ tempHumIndex()

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.

◆ tempOnDryAd()

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 WXP::ParcelParams::calc(), convTemp(), WXP::ThermPlot::draw(), lcl(), lclTemp(), and WXP::ParcelParams::set().

◆ tempOnMixRat()

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(), WXP::ThermPlot::draw(), lcl(), and WXP::ParcelParams::set().

◆ tempOnSatAd()

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 WXP::ParcelParams::calc(), WXP::ThermPlot::draw(), wetBulb(), and wetBulbPotTemp().

◆ tempVaporPres()

float Calc::tempVaporPres ( float e )

static

Temperature in Kelvin given a specific vapor pressure

Parameters

e	Vapor pressure in millibars

Referenced by dewTemp().

◆ thetaeOnSatAd()

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 WXP::ParcelParams::calc(), WXP::ThermPlot::draw(), equivPotTemp(), wetBulb(), and wetBulbPotTemp().

◆ vaporPres()

float Calc::vaporPres ( float t )

static

Saturation vapor pressure in millibars

Parameters

t	Temperature in Kelvin

References WXP::Const::MISS.

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

◆ virtPotTemp()

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::UpaCalc::calc(), and WXP::SfcDataTool::compute().

◆ virtTemp()

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::UpaCalc::calc(), WXP::SfcDataTool::compute(), and virtPotTemp().

◆ wetBulb()

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().

◆ wetBulbPotTemp()

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().

◆ windChill()

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

◆ windChillTemp()

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

◆ windChillTemp2()

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

◆ windDir()

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(), and WXP::Wind::setVect().

◆ windSpd()

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(), and WXP::Wind::setVect().

◆ windU()

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(), WXP::WindPlot::drawVect(), WXP::Wind::toVect(), and WXP::Wind::toVect().

◆ windV()

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(), WXP::WindPlot::drawVect(), WXP::Wind::toVect(), and WXP::Wind::toVect().

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

Calc.h
Calc.cc

Static Public Member Functions

Detailed Description

Member Function Documentation

◆ ADD()

◆ convTemp()

◆ dewTemp()

◆ DIF()

◆ dist()

◆ DIV()

◆ earthAngle()

◆ earthDist()

◆ equivPotTemp()

◆ heatIndex()

◆ humiture()

◆ interpLinear()

◆ interpTemp()

◆ lcl() [1/2]

◆ lcl() [2/2]

◆ lclPres()

◆ lclTemp()

◆ Max()

◆ Min()

◆ mixRatio()

◆ MUL()

◆ potTemp()

◆ presAlt()

◆ relHum()

◆ sfcPrAlt()

◆ specHum()

◆ tempHumIndex()

◆ tempOnDryAd()

◆ tempOnMixRat()

◆ tempOnSatAd()

◆ tempVaporPres()

◆ thetaeOnSatAd()

◆ vaporPres()

◆ virtPotTemp()

◆ virtTemp()

◆ wetBulb()

◆ wetBulbPotTemp()

◆ windChill()

◆ windChillTemp()

◆ windChillTemp2()

◆ windDir()

◆ windSpd()

◆ windU()

◆ windV()