Matlab - extraer numeros de un vector

a=[0 30 60 90 120 150 180];

par=a(2:2:length(a));

impar=a(1:2:length(a));

A=[ -4 23 2.343 33 4 4.55];

A(cellfun(@(x) ismember('4',num2str(x)),num2cell(A)))=nan;

disp(A)

A=[ -4 23 2.343 33 4 4.55]

for i=1:length(A)

if strfind(num2str(A(i)),'4')>=1

    A(i)=NaN;

end

end

A

>> numero_NaN

A =

   -4.0000   23.0000    2.3430   33.0000    4.0000    4.5500

A =

   NaN    23   NaN    33   NaN   NaN

>> A=[ -4 23 2.343 33 4 4.55]

A =

   -4.0000   23.0000    2.3430   33.0000    4.0000    4.5500

>> u=A(1)

u =

    -4

% https://www.lawebdelprogramador.com/foros/Matlab/1367921-extraer-numeros-de-un-vector.html#i1715335

clear

U=round(100*rand(1,20))

maximo=max(U)

valor=70/100*maximo

pos=find(U<valor);

valores=U(pos)

>> porcentaje1

U =

    31    92    43    18    90    98    44    11    26    41    59    26    60    71    22    12    30    32    42    51

maximo =

    98

valor =

   68.6000

valores =

    31    43    18    44    11    26    41    59    26    60    22    12    30    32    42    51