%usage:  val = get_num(str)

%This program extracts a number from the NanoScope header line in str.

%Jennifer R. Hampton  2/16/09

function val = get_num(str)

%Information based on Appendix B "Data File Format" from the NanoScope
%Command Reference Manual (Section B.6.3)

%CAIO header lines start with '\@' and have the following format
%\@X:Param: V [Soft-Scale] (Hard-Scale U) Hard-Value U
%X is single-digit number (group number)
%Param is the parameter label (may contain spaces)
%V stands for value parameter
%Soft-Scale is the soft-scale name
%Hard-Scale and Hard-Value are numbers with units (usually V/LSB and V
%respectively)
%The group number, the soft-scale and/or the hard-scale may be missing

%In these two cases of value parameters, the program will read the
%hard-value into val
%Case 1 (Hard-Scale U) is present in the line
%Case 2 [Soft-Scale] (Hard-Scale U) are absent in the line

%Non-CAIO parameters start with '\' and have the following format
%\Param: Value U
%Param is the parameter label (may contain spaces)
%Value is the value (with or without units)

%In this case (Case 3), the program will read the number into val

lim1a = findstr(str,'(');
lim1b = findstr(str,')');
lim2 = findstr(str,'V');
lim3 = findstr(str,':');

if length(lim1a)>0
    %Case 1 -- extract number after ')'
    %substr = str(lim1a+1:lim1b-1);
    %valp = sscanf(substr,'%f %*s');
    substr = str(lim1b+1:length(str));
    val = sscanf(substr,'%f %*s');
elseif length(lim2)>0
    %Case 2 -- extract number after 'V'
    substr = str(lim2+1:length(str));
    val = sscanf(substr,'%f %*s');
else
    %Case 3 -- extract number after ':'
    substr = str(lim3+1:length(str));
    val = sscanf(substr,'%f %*s');
end