Best practice to retrieve data from a large excel database based on GUI input

Hi all,

I was wondering if there is some established/fast way to quickly retrieving selected values from a large excel database.

I have a GUI that takes in data selection parameters in form of listbox values, each listbox corresponds to a value within a column. After the user inputs value linked to C1, C2, and C3, the program should be able to locate C4.

For example, user selects from popup menus: "1A", then "1.1", and finally "1". In this case, there are two C4 values for the same C1-C3. The GUI then displays the average of 107 and 123.5.

The challenge here is that I do not know beforehand how many C4 values exist for a particular combination of C1-C3.

% Simple version:
C1  C2  C3  C4

1A  1.1  1  107.0
1A  1.1  1  123.5
B  1.1  1  143.9
BB  1.4  2  166.8
C  1.1  1  193.5
C  1.3  2  235.5

This feels like it could be easily solved using logicals/matrix operations, but I can't seem to figure it out.

Answer 1

[Ingrid]

have you looked into the function ismember() with the option rows? It looks like this it what you are needing