function [ data, long, lat ] = import_asc( filename )
%
%Objective: Import .asc file and return matrixes of data and lat/long coordinates
%
%Example:
%	[data, long,lat]=import_asc('file.asc');
%	pcolor(long,lat,data); shading flat;
%
%Author: Ricardo Dal'Agnol da Silva (ricds@hotmail.com)
%
fid = fopen(filename,'r');
for i=1:6
    tmp=fgetl(fid);
    tmp=sscanf(tmp,'%s%f',[1 Inf]);
    tmp_s=size(tmp,2);
    header{i}=tmp(tmp_s);
end
[data,header{7}]=fscanf(fid,'%f');
fclose (fid);
n_col=header{1};
n_lin=header{2};
x_min=header{3};
y_min=header{4};
res=header{5};
null=header{6};
x_max=x_min+(n_col*res)-res;
y_max=y_min+(n_lin*res)-res;
[long,lat]=meshgrid(x_min:res:x_max,y_min:res:y_max);
data=flipud(reshape(data,header{1},header{2})');
data(data==null)=NaN;

end