atmoscoesa

Use 1976 COESA model

Syntax

[T,a,P,rho] = atmoscoesa(height)

[T,a,P,rho] = atmoscoesa(height,action)

Description

[T,a,P,rho] = atmoscoesa(height) implements the mathematical representation of the 1976 Committee on Extension to the Standard Atmosphere (COESA) United States standard lower atmospheric values. These values are absolute temperature, pressure, density, and speed of sound for the input geopotential altitude, height.

Below the geopotential altitude of 0 m (0 feet) and above the geopotential altitude of 84,852 m (approximately 278,386 feet), the atmoscoesa function extrapolates values.

[T,a,P,rho] = atmoscoesa(height,action) specifies the action for out-of-range input.

Examples

Calculate COESA Model at 1,000 Meters with Warnings Enabled

Calculate the COESA model at 1,000 meters with warnings for out-of-range inputs.

[T,a,P,rho] = atmoscoesa(1000)

T = 281.6500

a = 336.4341

P = 8.9875e+04

rho = 1.1116

Calculate COESA Model at 1,000, 11,000, and 20,000 Meters with Errors Enabled

Calculate the COESA model at 1,000, 11,000, and 20,000 meters with errors for out-of-range inputs.

[T,a,P,rho] = atmoscoesa([1000 11000 20000], 'Error')

T = 1×3

  281.6500  216.6500  216.6500

a = 1×3

  336.4341  295.0696  295.0696

P = 1×3
104 ×

    8.9875    2.2632    0.5475

rho = 1×3

    1.1116    0.3639    0.0880

Input Arguments

height — Geopotential heights

scalar | vector | matrix

Geopotential heights, specified as a scalar, vector, or matrix in meters.

Data Types: double

action — Action

'Warning' (default) | 'Error' | 'None'

Action for out-of-range input, specified as:

• 'Error' — Displays warning and indicates that the input is out of range.

• 'Warning' — Displays error and indicates that the input is out of range.

• 'None' — Does not display warning or error.

Data Types: char | string

Output Arguments

T — Temperatures

scalar | vector | matrix

Temperatures, returned as a scalar, vector, or matrix in the same size as the height argument, in kelvin. This function interpolates temperature values linearly.

a — Speeds of sound

scalar | vector | matrix

Speeds of sound, returned as a scalar, vector, or matrix in the same size as the height argument, in meters per second. This function calculates speed of sound using a perfect gas relationship.

P — Pressures

scalar | vector | matrix

Pressures, returned as a scalar, vector, or matrix in the same size as the height argument, in pascal. This function logarithmically calculates pressure.

rho — Densities

scalar | vector | matrix

Densities, returned as a scalar, vector, or matrix in the same size as the height argument, in kilograms per meter cubed. This function interpolates density values using a perfect gas relationship.

References

[1] U.S. Standard Atmosphere, 1976, U.S. Government Printing Office, Washington, D.C.

Version History

Introduced in R2006b

R2021b: atmoscoesa function changed input and returned value formats

Behavior changed in R2021b

The atmoscoesa function now:

• Accepts scalar, vector, or matrix values.

• Outputs scalar, vector, or matrix values.

As a result, the output values from this function might change from previous releases.