sera-applications/SHAPE_Package/SHAPE_ver2.0/SSH/Max_credM_GRT.m

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% [T,m]=Max_credM_GRT(Td,Tu,dT,Mmin,lamb,eps,b,Mmax)
%EVALUATES THE MAXIMUM CREDIBLE MAGNITUDE VALUES USING THE UPPER-BOUNDED
% G-R LED MAGNITUDE DISTRIBUTION MODEL.
%
% AUTHOR: S. Lasocki 06/2014 within IS-EPOS project.
%
% DESCRIPTION: The assumption on the upper-bounded Gutenberg-Richter
% relation leads to the upper truncated exponential distribution to model
% magnitude distribution from and above the catalog completness level
% Mmin. The shape parameter of this distribution, consequently the G-R
% b-value and the end-point of the distriobution Mmax as well as the
% activity rate of M>=Mmin events are calculated at start-up of the
% stationary hazard assessment services in the upper-bounded
% Gutenberg-Richter estimation mode.
%
% The maximum credible magnitude values are calculated for periods of
% length starting from Td up to Tu with step dT.
%
% INPUT:
% Td - starting period length for maximum credible magnitude calculations
% Tu - ending period length for maximum credible magnitude calculations
% dT - period length step for maximum credible magnitude calculations
% Mmin - lower bound of the distribution - catalog completeness level
% lamb - mean activity rate for events M>=Mmin
% eps - length of the round-off interval of magnitudes.
% b - Gutenberg-Richter b-value
% Mmax - upper limit of magnitude distribution
%
% OUTPUT:
% T - vector of independent variable (period lengths) T=(Td:dT:Tu)
% m - vector of maximum credible magnitudes of the same length as T
%
% LICENSE
% This file is a part of the IS-EPOS e-PLATFORM.
%
% This is free software: you can redistribute it and/or modify it under
% the terms of the GNU General Public License as published by the Free
% Software Foundation, either version 3 of the License, or
% (at your option) any later version.
%
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
% GNU General Public License for more details.
%
function [T,m]=Max_credM_GRT(Td,Tu,dT,Mmin,lamb,eps,b,Mmax)
% -------------- VALIDATION RULES ------------- K_21NOV2016
if dT<=0;error('Time Step must be greater than 0');end
%----------------------------------------------------------
T=(Td:dT:Tu)';
beta=b*log(10);
mian=(1-exp(-beta*(Mmax-Mmin+eps/2)));
m=Mmin-eps/2-1/beta*log((1-(1-1./(lamb*T))*mian));
end