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# db2mag

Convert decibels to magnitude

## 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

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### 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

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### 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

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### 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.