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Conversion to dB (decibels) in 20*log10 Form
 Syntax `y = db20(`x`)` Include: `include spt\db20.oms` See Also db10
``` ARGUMENTS:    INPUTS:      x = MATRIX, any numerical type    RETURN: MATRIX, 20*log10(x), type DOUBLE ```
Description ``` ```Returns the element-by-element value of twenty times the log base ten of the input matrix. Any numerical type may be input. INTEGER, REAL, and DOUBLE type are coerced to DOUBLE for internal processing. COMPLEX types are converted to their ABSOLUTE VALUE before local processing. Type returned is always DOUBLE. ``` ```This function is appropriate for quantities that may be interpreted as a fundamental quantity, such as amplitude, volts, etc. Input is converted to absolute value before processing to preserve the relative strength. If ZERO is input, a decibel value corresponding to the DOUBLE_EPSILON is returned.

Example ``` ```For vectors: ``` O>x = {-2, -1, 0, 2, 4, 20} O>db20(x) { 6.0206 0 -313.071 6.0206 12.0412 26.0206 } ``` For complxe values: ``` O>db20(3d0 + 4i0) 13.9794  ``` For matrices: ``` O>A = {[-10, 5],[.5, .125]} O>db20(A) { [ 20 , 13.9794 ] [ -6.0206 , -18.0618 ] } ```