function plms= plotmsem(xaxis, yvalues, colorvs, alpha, linespec, linewidth, mflag)
%plotmsem plots mean +/- sem with shaded, continuous error bars

if nargin <7
if nargin < 6
    if nargin < 5
        if nargin < 4
            alpha=.1;
        end
        linespec='-'; 
    end
    linewidth=2;
end
mflag=1; % plot mean, mflag=2 plot median
end

if nargin>=3 && ischar(colorvs) && contains('kbgcrmyw',colorvs(1))
    color=rem(floor((strfind('kbgcrmyw',colorvs(1))-1)*[.25 .5 1]),2);
    if length(colorvs)>1
        linespec=colorvs(2:end);
    end
elseif nargin>=3 && isa(colorvs,'double')
    color=colorvs(1:3);
else 
    color=[0 0 0];
end

if ~isvector(xaxis)
    error('x-axis vector has to be 1D.');
elseif iscolumn(xaxis)
        xaxis=xaxis';
end

if ~ismatrix(yvalues)
        error('y-values matrix has to be 2D.');
end

if ~any(size(yvalues)==length(xaxis))
    error('x-axis and y-values must have equal size along 1D (at least).');
end

% force xaxis and yvalues to have same number of rows (not columns)
if size(yvalues,2)~=length(xaxis)
    yvalues=yvalues';  
end

% mean and sem are computed along rows
if mflag==1
    myv=nanmean(yvalues,1);
elseif mflag==2
    myv=nanmedian(yvalues,1);
end
semyv=nansem(yvalues,1);

plms.semfill=fill([xaxis xaxis(end:-1:1)]',[myv-semyv myv(end:-1:1)+semyv(end:-1:1)]',color,'facealpha',alpha,'linestyle','none'); hold on;
plms.meanline=plot(xaxis,myv,linespec,'Color',color,'Linewidth',linewidth);

end