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# atmoscoesa

Use 1976 COESA model

## Syntax

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

## Description

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

Below the geopotential altitude of 0 m (0 feet) and above the geopotential altitude of 84,852 m (approximately 278,386 feet), the function extrapolates values. It extrapolates temperature values linearly and pressure values logarithmically.

## Input Arguments

height

Array of m-by-1 geopotential heights, in meters.

action

String that defines action for out-of-range input. Specify one:

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

## Output Arguments

 T Array of m-by-1 temperatures, in kelvin. a Array of m-by-1 speeds of sound, in meters per second. The function calculates speed of sound using a perfect gas relationship. P Array of m-by-1 pressures, in pascal. Rho Array of m-by-1 densities, in kilograms per meter cubed. The function calculates density using a perfect gas relationship.

## Examples

Calculate the COESA model at 1000 m with warnings for out-of-range inputs:

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

T =

281.6500

a =

336.4341

P =

8.9875e+004

rho =

1.1116```

Calculate the COESA model at 1000, 11,000, and 20,000 m with errors for out-of-range inputs:

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

T =

281.6500  216.6500  216.6500

a =

336.4341  295.0696  295.0696

P =

1.0e+004 *

8.9875    2.2632    0.5475

rho =

1.1116    0.3639    0.0880```

## References

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