# atmosisa

Use International Standard Atmosphere model

## Syntax

``````[T, a, P, rho] = atmosisa(height)``````

## Description

example

``````[T, a, P, rho] = atmosisa(height)``` implements the mathematical representation of the International Standard Atmosphere values for ambient temperature, pressure, density, and speed of sound for the input geopotential altitude.This function assumes that temperature and pressure values are held constant for both:Below the geopotential altitude of 0 kmAbove the geopotential altitude of the tropopause (at 20 km)```

## Examples

collapse all

Calculate the International Standard Atmosphere at 1000 m.

`[T, a, P, rho] = atmosisa(1000)`
```T = 281.6500 ```
```a = 336.4341 ```
```P = 8.9875e+04 ```
```rho = 1.1116 ```

Calculate the International Standard Atmosphere at 1000, 11,000, and 20,000 m.

`[T, a, P, rho] = atmosisa([1000 11000 20000])`
```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

collapse all

Geopotential heights, specified as an m-by-m array.

Data Types: `double`

## Output Arguments

collapse all

Temperatures, returned as an m-element array, in kelvin.

Speeds of sound, returned as an m-element array, in meters per second. The function calculates speed of sound using a perfect gas relationship.

Pressures, returned as an m-element array, in pascal.

Densities, returned as an m-element array, in kilograms per meter cubed. The function calculates density using a perfect gas relationship.

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

## Support Get trial now