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Reference guides are available for functions and commands supported by OML, Tcl, and Python.
Reference Guide for OpenMatrix Language Functions
The Reference Guide contains documentation for all functions supported in the OpenMatrix language.
Control System Commands
db2mag
Transforms decibels (dB) to magnitude.

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- Scripting Guide for OpenMatrix Language
  OpenMatrix is a mathematical scripting language.
- Reference Guide for OpenMatrix Language Functions
  The Reference Guide contains documentation for all functions supported in the OpenMatrix language.
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      Ackermann's formula (pole placement gain selection for single-input systems).
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      Computes a Gramian balanced realization of an LTI model.
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      Block diagonalization with the Schur factorization.
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      Bode diagram.
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      Computes a discrete-time state-space model from a continuous-time state-space model.
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      Solves the continuous-time Algebraic Riccati Equation.
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      Steady-state co-variance.
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      Controllability matrix.
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      Converts a discrete model to continuous time model.
    - damp
      Compute natural frequencies, damping ratios, and poles.
    - dare
      Solves the Discrete-time Algebraic Riccati Equations.
    - db2mag
      Transforms decibels (dB) to magnitude.
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      Low-frequency (DC) gain of a state-space or transfer function model
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      Linear-quadratic regulator for a discrete-time model.
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      Solve discrete-time Lyapunov or Sylvester equations.
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      Constructs a descriptor state-space model.
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      Extracts data from a descriptor state-space model.
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      Sorts continuous-time poles in descending order by the real component.
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      Returns the state estimator for a given estimator gain.
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      Compute the matrix exponential.
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      Constructs a transfer function model in DSP format.
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      Generates an input signal for the lsim function.
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      Hankel singular values of a state-space or transfer function model.
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      Compute the impulse response of a control system.
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      Matrix logarithm.
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    - lyap
      Solves continuous Lyapunov or Sylvester equations.
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      Solves continuous-time Lyapunov equation using a square-root solver.
    - mag2db
      Computes magnitude from decibels (dB).
    - margin
      Margin stability.
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      Minimal realization.
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      Nyquist diagram.
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      Returns the observability matrix of a state-space model.
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      Calculates the observability staircase form.
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      Computes the Pade approximation of time delays.
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      Constructs a continuous-time PID controller transfer function.
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      Pole assignment.
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      Compute poles for a state-space or transfer function model.
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      Scale a state-space model.
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      Creates a state regulator with specified state-feedback and estimator gains.
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      Find gain and poles for specific points of a root locus diagram.
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      rlocus diagram.
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      Transforms a real Schur form to a complex Schur form.
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      Connects two state-space or transfer function in a series.
    - sqrtm
      Matrix square root.
    - ss
      Constructs a state-space model.
    - ss2ss
      Transforms a state-space model to another state-space model.
    - ss2tf
      Converts state-space model parameters to transfer function model parameters.
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      Convert state-space model parameters to transfer function model parameters.
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      Extracts data from a state-space model.
    - step
      Compute the step response of a control system.
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      Constructs a transfer function model
    - tf2ss
      Transforms transfer function parameters to state-space parameters.
    - tf2ssc
      Transforms transfer function parameters to state-space parameters.
    - tf2zp
      Transforms (continuous) transfer function parameters to zero-pole-gain parameters.
    - tf2zpk
      Transforms (discrete) transfer function parameters to zero-pole-gain parameters.
    - tfdata
      Extracts data from a transfer function model.
    - zp2ss
      Zero-pole to state-space conversion.
    - zp2tf
      Zero-pole to transfer function conversion.
    - zpk
      Constructs a zero, pole, gain model.
    - zpkdata
      Extracts data from a zero-pole-gain model.
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db2mag

Transforms decibels (dB) to magnitude.

Syntax

Y = db2mag(YDB)

Inputs

YDB: A matrix.

Examples

Single value input:

m = db2mag(2)

m = 1.25892541

Matrix input:

mg = db2mag([1 2; -10 -12])

mg = [Matrix] 2 x 2
1.12202  1.25893
0.31623  0.25119

Comments

Y = db2mag(YDB) returns the variable 'Y' corresponding to a YDB decibel value given (dB).

The formula between magnitude and decibels is ydb = 20 * log10(y).