# db2mag

Convert decibels to magnitude

## Syntax

• `y = db2mag(ydb)` example

## Description

example

````y = db2mag(ydb)` returns the magnitude measurements, `y`, that correspond to the decibel (dB) values specified in `ydb`. The relationship between magnitude and decibels is `ydb` = 20 log10(`y`).```

## Examples

collapse all

### Magnitudes of Random Numbers

Generate a 2-by-4-by-2 array of Gaussian random numbers. Assume the numbers are expressed in decibels and compute the corresponding magnitudes.

```r = randn(2,4,2); mags = db2mag(r) ```
```mags(:,:,1) = 1.0639 0.7710 1.0374 0.9513 1.2351 1.1044 0.8602 1.0402 mags(:,:,2) = 1.5098 0.8561 1.0871 1.0858 1.3755 1.4182 0.9928 0.9767 ```

Use the definition to check the calculation.

```chck = 10.^(r/20) ```
```chck(:,:,1) = 1.0639 0.7710 1.0374 0.9513 1.2351 1.1044 0.8602 1.0402 chck(:,:,2) = 1.5098 0.8561 1.0871 1.0858 1.3755 1.4182 0.9928 0.9767 ```

## Input Arguments

collapse all

### `ydb` — Input array in decibelsscalar | vector | matrix | N-D array

Input array in decibels, specified as a scalar, vector, matrix, or N-D array. When `ydb` is nonscalar, `db2mag` is an element-wise operation.

Data Types: `single` | `double`

## Output Arguments

collapse all

### `y` — Magnitude measurementsscalar | vector | matrix | N-D array

Magnitude measurements, returned as a scalar, vector, matrix, or N-D array of the same size as `ydb`.