How to use the parameters of other functions within the ‘cellfun’ function?

Hello guys, just a simple question. I don’t find the way how to use the parameters ‘movemedian’ , ‘lowess’ and so on .. belonging to the ‘smoothdata’ function inside the ‘cellfun’ , how can you do this? Thank you.

x=cellfun(@smoothdata,C1,('movemedian',100),'UniformOutput',false); %there is a mistake here calling the parameters for 'smoothdata'

Answer 1

[Stephen23]

https://www.mathworks.com/help/matlab/math/parameterizing-functions.html

f = @(a)smoothdata(a,'movemedian',100);
x = cellfun(f,C1,'UniformOutput',false);

[Fercho_Sala]

it worked like that, thank's a lot ;)

[Fercho_Sala]

@Stephen Cobeldick what about for the 'findpeaks' function? ; having a structure like this:

[pks,locs,widths,proms] = findpeaks(r,y,'MinPeakHeight',20); widths; proms;
findpeaks(r,y,'Annotate','extents','WidthReference','halfprom');

the 'cellfun' funtion it wont work propertly.

[Stephen23]

Y = {1:7,1:7};
R = {50*rand(1,7),50*rand(1,7)};
F = @(r,y)findpeaks(r,y,'MinPeakHeight',20,'Annotate','extents','WidthReference','halfprom');
[pks,locs,widths,proms] = cellfun(F,R,Y,'uni',0)

pks = 1×2 cell array
    {[30.0986]}    {[44.1002]}

locs = 1×2 cell array
    {[6]}    {[3]}

widths = 1×2 cell array
    {[0.9610]}    {[2.6194]}

proms = 1×2 cell array
    {[17.1221]}    {[32.4057]}

Note that you can always just use a loop: CELLFUN is handy in some circumstances where it can compact an operation down to a neat line or so of code, but it is slower than a loop and not always simpler.

[Fercho_Sala]

@Stephen Cobeldick ok, and how can I do loop for this case?

[Fercho_Sala]

@Stephen Cobeldick I was triying to do a loop in this way..

 FigH = figure;
for cv=1:numel(smt1)
    ax1=subplot(4, 6, cv6, 'Parent', FigH);
     [pks,locs,widths,proms] = findpeaks((smt1{1,cv}(:,end)),y,'MinPeakHeight',20); widths; proms;
     findpeaks((smt1{1,cv}(:,end)),y,'Annotate','extents','WidthReference','halfprom');
     text(locs+0.5,pks,num2str((1:numel(pks))'));
     legend('Filtered Data','Peak','Prominence','Width','FontSize',5);
end

but it doesn't work.

[Stephen23]

"but it doesn't work."

I have no idea what you expect to occur, nor did you write what actually happens.

[Fercho_Sala]

@Stephen Cobeldick it's the way how the loop was formulated for ths case, but there is Something wrong with the syntaxis, the idea is to do a loop for the variable smt showing its respective plots and as a result [pks,locs,widths,proms] as cell array.

[Stephen23]

If you want to keep pks, etc. to use after the loop then you will need to use indexing into some variable, e.g.:

N = numel(smt1);
pks    = cell(1,N);
locs   = cell(1,N);
widths = cell(1,N);
proms  = cell(1,N);
for cv = 1:N
    ..
    [pks{cv},locs{cv},widths{cv},proms{cv}] = findpeaks(..);
    ..
end

https://www.mathworks.com/help/matlab/matlab_prog/access-data-in-a-cell-array.html

[Fercho_Sala]

@Stephen Cobeldick thank's.. using your structure is the best and the fastest solution.