Q_DT_MMAPK_ParsePara.m

function Q_DT_MMAPK_ParsePara(D0,D0_name,D,D_name)
%Q_DT_MMAPK_ParsePara checks the validity of the input matrices D0, D as a
%representation of a Discrete-Time MMAP[K]. D{i} holds the mxm matrix D_i.
 
% check numeric 
if (~isnumeric(D0))
    error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
        '%s has to be numeric', D0_name);
end
K=size(D,2);
for i=1:K
    if (~isnumeric(D{i}))
        error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
            '%s_%d has to be numeric',D_name, i);
    end 
end
 
% check real
if (~isreal(D0))
    error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
        '%s has to be a real matrix', D0_name);
end
for i=1:K
    if (~isreal(D{i}))
        error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
            '%s_%d has to be a real matrix',D_name,i);
    end    
end
 
% check dimension
if (size(D0,1) ~= size(D0,2))
    error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
        '%s is not a square matrix', D0_name);
end
for i=1:K
    if (size(D{i},1) ~= size(D{i},2))
        error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
            '%s_%d is not a square matrices',D_name,i);
    end   
end
 
if (size(D0,1) ~= size(D{1},1))
    error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
        'The matrices %s and %s_1 do not have the same dimension', D0_name, D_name);
end   
for i=1:K-1
    if (size(D{i},1) ~= size(D{i+1},1))
        error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
            'The matrices %s_%d and %s_d do not have the same dimension',D_name,i,D_name,i+1);
    end   
end
 
% check nonnegativity
if (min(min(D0)) < -10^(-14))
    error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
        'The matrix %s contains negative data', D0_name);
end
for i=1:K
    if (min(min(D{i})) < -10^(-14))
        error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
            'The matrix %s_%d contains negative data',D_name,i);
    end    
end    
 
% check (sub)stochasticity
if (max(sum(D0,2)) > 1+10^(-14))
    error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
        'The matrix %s has to be substochastic', D0_name);
end    
Dsum = D0;
for i = 1:K
    Dsum = Dsum + D{i};
end
if (max(sum(Dsum,2)) > 1+10^(-14))||(min(sum(Dsum,2)) < 1-10^(-14))
    error('MATLAB:Q_DT_MMAPK_ParsePara:InvalidInput',...
        'The matrix %s+%s_1+...+%s_K has to be stochastic', D0_name,D_name,D_name);
end