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Decibel

The decibel module contains basic functions for decibel arithmetic.

Functions

dbsum 

dbsum(levels, axis=None) -> float

Energetic summation of levels.

PARAMETER DESCRIPTION
levels

Sequence of levels.
axis

Axis over which to perform the operation. $$ L_{sum} = 10 \log_{10}{\sum_{i=0}^n{10^{L/10}}} $$

DEFAULT: None

RETURNS DESCRIPTION
float

Energetic summation of levels.
Source code in acoustic_toolbox/decibel.py 
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def dbsum(levels, axis=None) -> float:
    r"""Energetic summation of levels.

    Args:
      levels: Sequence of levels.
      axis: Axis over which to perform the operation.
        $$
        L_{sum} = 10 \log_{10}{\sum_{i=0}^n{10^{L/10}}}
        $$

    Returns:
        Energetic summation of levels.
    """
    levels = np.asanyarray(levels)
    return 10.0 * np.log10((10.0 ** (levels / 10.0)).sum(axis=axis))

dbmean 

dbmean(levels, axis=None) -> float

Energetic average of levels.

PARAMETER DESCRIPTION
levels

Sequence of levels.
axis

Axis over which to perform the operation. $$ L_{mean} = 10 \log_{10}{\frac{1}{n}\sum_{i=0}^n{10^{L/10}}} $$

DEFAULT: None

RETURNS DESCRIPTION
float

Energetic average of levels.
Source code in acoustic_toolbox/decibel.py 
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def dbmean(levels, axis=None) -> float:
    r"""Energetic average of levels.

    Args:
      levels: Sequence of levels.
      axis: Axis over which to perform the operation.
        $$
        L_{mean} = 10 \log_{10}{\frac{1}{n}\sum_{i=0}^n{10^{L/10}}}
        $$

    Returns:
        Energetic average of levels.
    """
    levels = np.asanyarray(levels)
    return 10.0 * np.log10((10.0 ** (levels / 10.0)).mean(axis=axis))

dbadd 

dbadd(a: float | ndarray, b: float | ndarray) -> float

Energetic addition.

Energetically adds b to a.

$$ L_{a+b} = 10 \log_{10}{10^{L_b/10}+10^{L_a/10}} $$

PARAMETER DESCRIPTION
a

Single level or sequence of levels.

TYPE: float | ndarray

b

Single level or sequence of levels.

TYPE: float | ndarray

RETURNS DESCRIPTION
float

Energetic addition of a and b.
Source code in acoustic_toolbox/decibel.py 
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def dbadd(a: float | np.ndarray, b: float | np.ndarray) -> float:
    r"""Energetic addition.

    Energetically adds b to a.

      $$
      L_{a+b} = 10 \log_{10}{10^{L_b/10}+10^{L_a/10}}
      $$

    Args:
      a: Single level or sequence of levels.
      b: Single level or sequence of levels.


    Returns:
        Energetic addition of a and b.
    """
    a = np.asanyarray(a)
    b = np.asanyarray(b)
    return 10.0 * np.log10(10.0 ** (a / 10.0) + 10.0 ** (b / 10.0))

dbsub 

dbsub(a: float | ndarray, b: float | ndarray) -> float

Energetic subtraction.

Energitally subtract b from a.

\[ L_{a-b} = 10 \log_{10}{10^{L_a/10}-10^{L_b/10}} \]
PARAMETER DESCRIPTION
a

Single level or sequence of levels.

TYPE: float | ndarray

b

Single level or sequence of levels.

TYPE: float | ndarray

RETURNS DESCRIPTION
float

Energetic subtraction of a and b.
Source code in acoustic_toolbox/decibel.py 
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def dbsub(a: float | np.ndarray, b: float | np.ndarray) -> float:
    r"""Energetic subtraction.

    Energitally subtract b from a.

    $$
    L_{a-b} = 10 \log_{10}{10^{L_a/10}-10^{L_b/10}}
    $$

    Args:
      a: Single level or sequence of levels.
      b: Single level or sequence of levels.

    Returns:
        Energetic subtraction of a and b.
    """
    a = np.asanyarray(a)
    b = np.asanyarray(b)
    return 10.0 * np.log10(10.0 ** (a / 10.0) - 10.0 ** (b / 10.0))

dbmul 

dbmul(levels, f, axis=None) -> ndarray

Energetically add levels f times.

\[ L_{sum} = 10 \log_{10}{\sum_{i=0}^n{10^{L/10} \cdot f}} \]
PARAMETER DESCRIPTION
levels

Sequence of levels.
f

Multiplication factor f.
axis

Axis over which to perform the operation.

DEFAULT: None

RETURNS DESCRIPTION
ndarray

Resulting levels after energetic addition.
Source code in acoustic_toolbox/decibel.py 
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def dbmul(levels, f, axis=None) -> np.ndarray:
    r"""Energetically add `levels` `f` times.

    $$
    L_{sum} = 10 \log_{10}{\sum_{i=0}^n{10^{L/10} \cdot f}}
    $$

    Args:
      levels: Sequence of levels.
      f: Multiplication factor `f`.
      axis: Axis over which to perform the operation.

    Returns:
        Resulting levels after energetic addition.
    """
    levels = np.asanyarray(levels)
    return 10.0 * np.log10((10.0 ** (levels / 10.0) * f).sum(axis=axis))

dbdiv 

dbdiv(
    levels: float | ndarray,
    f: float,
    axis: int | None = None,
) -> ndarray

Energetically divide levels f times.

\[ L_{sum} = 10 \log_{10}{\sum_{i=0}^n{10^{L/10} / f}} \]
PARAMETER DESCRIPTION
levels

Sequence of levels.

TYPE: float | ndarray

f

Divider f.

TYPE: float

axis

Axis over which to perform the operation.

TYPE: int | None DEFAULT: None

RETURNS DESCRIPTION
ndarray

Resulting levels after energetic division.
Source code in acoustic_toolbox/decibel.py 
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def dbdiv(levels: float | np.ndarray, f: float, axis: int | None = None) -> np.ndarray:
    r"""Energetically divide `levels` `f` times.

    $$
    L_{sum} = 10 \log_{10}{\sum_{i=0}^n{10^{L/10} / f}}
    $$

    Args:
      levels: Sequence of levels.
      f: Divider `f`.
      axis: Axis over which to perform the operation.

    Returns:
        Resulting levels after energetic division.
    """
    levels = np.asanyarray(levels)
    return 10.0 * np.log10((10.0 ** (levels / 10.0) / f).sum(axis=axis))

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