find maximum value indices

Im trying to find the indices number of the max of a certain function.

    delcx(:,n) = (massch4(max(longm(dataind{n}))))

I want to find the massch4 at the location where longm is a max value. Can I do that in one line? Can I use the find function?

Thanks!

[per isakson]

Why should we guess regarding massch4, longm and dataind? Please tell us about class, size and value. An example might be appropriate.

[shobhit mehrotra]

Hello,

massch4 is 1x30000 vector

longm is 1x30000 vector

dataind contains of indices stored in an array

[per isakson]

• "Can I do that in one line?" &nbsp It's easier to break it up in small steps and confirm that it works correctly. Lastly, one may combine it into one line.
• "in an array" &nbsp cell array I assume

    ixn = dataind{ n }; 
    lgm = longm( ixn );
    mxl = max( lgm );
    ms4 = massch4( mxl );

mxl and ms4 will be scalars. Will lgm and mxl be whole number suitable as indicies? What did I miss?

[shobhit mehrotra]

Hi it works, but this for a For Loop, how would I modify it, I tried to subscript (n) but it didnt work

this is what i got

    for n=1:20
        ixn(n) = longm(dataind{ n }); 
        lgm(n) = longm( ixn );
        mxl(n) = max( lgm );
        ms4(n) = massch4( mxl );
    end

Thanks!

[per isakson]

This looks strange! Why

    ixn(n) = longm(dataind{ n });

rather than

    ixn(n) = dataind{ n };

Isn't it time you

• start using the {}Code button and
• provide some sample data: input and required output

[shobhit mehrotra]

Can I use this function

    for n=1:20
        indm(n)= (find(longm == max(longm((dataind{n})))))
    end

The output should be a vector of indices of length n.

Thanks

[per isakson]

Did you try it? Whether it will work or not depends on the input data. You might preallocate memory for indm.

   indm = nan(1,20);
   for n=1:20
        indm(n) = find( longm == max(longm(dataind{n})) );
   end

What happened to massch4?

[shobhit mehrotra]

It works except if there is more than one indices it lists them both, I want it to only list the first indices in case of more than one. Thanks

[shobhit mehrotra]

I have that in another line, once I can get the indices Ill substitute it in

[per isakson]

Replace

    find( longm == max(longm(dataind{n})) )

by

    find( longm == max(longm(dataind{n})), 1, 'first' )