dbs.m

来自「A MATLAB tool for analysis of Transient 」· M 代码 · 共 20 行

function Sdb = dbs(S, limit, z)

%	Sdb = dbs(S, limit, z)
%
%	dbs	converts vector S into decibels. Square decibels
%		are used 10*log(S).
%
%   in:	S	complex vector
%	limit	down limit of decibel scale (for zero values) (default -100)
%	z	if present, the maximum db value is normalized to zero
%
%  out:	Sdb	real vector of decibel values

%	Heimo Ihalainen 20.12.1987 (2.11.1989 HI)

if nargin<2; limit = -100; end
if nargin<3; m = 1; else m = max(max(abs(S))); end

Sdb = 10*log10(max(abs(S)/m,10^(limit/10)));