Matlab Function

[rawger]

Hi All,
I am stuck at a point in writing some code.

Please look at this function Look at this function
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[FONT=&quot]%% Converting Cumulative "R" Values into Quarterly "Q" Values[/FONT]
[FONT=&quot]% For the first quarter, "R" data and "Q" data are equivalent. For[/FONT]
[FONT=&quot]% subsequent quaters (2, 3, & 4) the "Q" value is equivanet to the[/FONT]
[FONT=&quot]% current quarter's value less the previous quater's value.[/FONT]
[FONT=&quot] 1) [/FONT][FONT=&quot]function[/FONT][FONT=&quot] r = rToQ(obj)[/FONT]
[FONT=&quot] 2) [/FONT][FONT=&quot]if[/FONT][FONT=&quot] obj.freq ~= [/FONT][FONT=&quot]'R'[/FONT][FONT=&quot], error([/FONT][FONT=&quot]'obj frequency bust be "R"'[/FONT][FONT=&quot]); [/FONT][FONT=&quot]end[/FONT][FONT=&quot];[/FONT]
[FONT=&quot] 3) r = ifthen(obj.periods()==1, obj, obj - obj.lag(-1));[/FONT]
[FONT=&quot] 4) r.freq = [/FONT][FONT=&quot]'Q'[/FONT][FONT=&quot];[/FONT]
[FONT=&quot] 5) [/FONT][FONT=&quot]end[/FONT]

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As you can see the above function is used to change the cumulative data into quarterly data. I am trying to implement an ‘if else’ function
I am trying to create function called “ifthen” in Matlab (it is being called in line 4 in the code above) which checks for the period of the object. If it is 1 then the object remains unchanged. If is not 1 then the obj.lag is subtracted from the original obj.

How should I implement this “ifthen” function so that it returns an object? In other words how do I implement an element wise “ifthen “function on an object?
I tried to do something like this but this does not work on an object

[FONT=&quot]function[/FONT][FONT=&quot] r = ifthis( condition, result1, result2)[/FONT]
[FONT=&quot] error(nargchk(3,3,nargin));[/FONT]
[FONT=&quot]if condition == ([/FONT][FONT=&quot]obj.periods()==1[/FONT])
[FONT=&quot] r = obj;[/FONT]
[FONT=&quot]else[/FONT]
[FONT=&quot] r = obj-obj.lag(-1);[/FONT]
[FONT=&quot]end[/FONT]
[FONT=&quot]end[/FONT]


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<o:p>Any help would be appreciated</o:p>

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<o:p>-Thanks
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