function plpc=plotperc(xaxis, yvalues, percvals, colorvs, alpha)

if nargin<5
    alpha=.1;
end
if nargin>=4 && ischar(colorvs) && contains('kbgcrmyw',colorvs(1))
    color=rem(floor((strfind('kbgcrmyw',colorvs(1))-1)*[.25 .5 1]),2);
elseif nargin>=4 && isa(colorvs,'double')
    color=colorvs(1:3);
else
    color=[0 0 0];
end
if nargin<3
    percvals=[05 95];
end

if ~any(size(percvals)==2)
    error('percvals input is not correct');
end
if size(percvals,1)==2 && size(percvals,2)~=2
    percvals=percvals';
end

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

for vv=1:size(percvals,1)
    perc2=prctile(yvalues,percvals(vv,2),1);
    if(percvals(1)==-inf)
        perc1=repmat(min(get(gca,'YLim')),1,length(xaxis));
    else
        perc1=prctile(yvalues,percvals(vv,1),1);
    end
    
    %perc1(perc1<1e-50)=nan; % hardcoded fix for singularities
    %perc2(perc2<1e-50)=nan; % hardcoded fix for singularities
    
    pp=[perc1 perc2(end:-1:1)]';
    xp=[xaxis xaxis(end:-1:1)]';
    
    hold on;
    %fill([xaxis xaxis(end:-1:1)]',[perc1 perc2(end:-1:1)]',color,'facealpha',alpha,'linestyle','none'); hold on;
    plpc(vv).fill=fill(xp(isfinite(pp)),pp(isfinite(pp)),color,'facealpha',alpha,'linestyle','none'); hold on;
end


end