Is there a function in MATLAB 7.6 (R2008a) equal to VLOOKUP in Excel?

I would like to know if there exists a function in MATLAB that is equivalent to the VLOOKUP function in Excel.

I have created the following matrix in MATLAB:

   mydata=[datenum('1/31/2008') 3;    datenum('2/28/2008') 5];

I would like to search for a lookup_value in the first column of an array. If there exists a value in the first column of an array that is matching the lookup_value (exact match), then the function should return a value in the same row from another column in the array. If an exact match does not exists, the function should return the next largest value that is less than lookup_value.

For example, for the matrix above,

myMatch= fcm(mydata,datenum('2/7/2008'))

should output

 myData=
              3

Answer 1

[MathWorks Support Team]

This functionality does not exist as a builtin command in MATLAB 7.6 (R2008a). However it can be easily implemented by, for example, this function:

% FCM find an exact or approximate match
%
% mData = fcm(mydata, lookup_value)
%
% Will return an exact or approximate match. If an exact match is not
% found, the next largest value that is less than lookup_value is returned.
function mData = fcm(data, lookup_value)

dist = abs(data(:,1)-lookup_value); % Find distance to numbers in list
[min_val, min_loc] = min(dist); % Find minimum value

if data(min_loc,1)<=lookup_value
    mData = data(min_loc,2);
else
    try
        mData = data(min_loc-1,2);
    catch ME
        if ME.identifier=='MATLAB:badsubscript',
            error('The lookup_value must be greater than the smallest value in 1st column of the lookup array'),end
        mData=NaN;
    end
end

This function returns an error if the lookup_value is smaller than the smallest number in the 1st column of the lookup array.

Note that if you are using the data type table you can achieve this kind of functionality by accessing the value via the row name ( T.Value('rowname')).