function output = hex2uint8(instr)
% HEX2UINT8 -- Hexidecimal string converter.
% Converts hexdecimal ascii into unsigned 8 bit integer.
% Used for reading hydrorad files from oasis.
% 
% Use as: hex2uint8(instr)
% Inputs: instr = string of hex characters
% Output: output = a vector of integers which can be converted
%         into characters by using char(output)
%

% Created by K.M. Flynn
% Documented by E.Palomino; 20 Sep 2000

n = length(instr)/2;
tmpstr = double(instr) - 48;
tmpstr(find(tmpstr>9)) = tmpstr(find(tmpstr>9)) - 7;
tmpstr(find(tmpstr>15)) = tmpstr(find(tmpstr>15)) - 32;
tmpout = [];
for i=1:n
   j=2*(i-1)+1;
   tmpout(i) = 16*tmpstr(j) + tmpstr(j+1);
end
output = tmpout;