Double "for loop" with an integral of hundle functions, problem.

>> %assing two handle functions to a column with two rows

f1=@(t)3*t+1;

f2=@(t)1.5*t+0.5;

fcell=cell(2,1);

fcell{1}=f1;

fcell{2}=f2;

>> % gives me a 2x1 cell array, with @(t)3*t+1 in the first row

>> % and @(t)1.5*t+0.5 in the second row.

>> % I will use this cell array in a double "for loop" to produce something

>> C=sym(zeros(2,1));

for kk=1:2

for jj=1:2

C(kk)=C(kk)+integral(@(t)fcell{kk}(t),0,1);

end

end

>> % This, gives me 2 resaults, in a 2x1 sym. The first resault is :

>> C(1)

ans =

5

>> % and the second is :

>> C(2)

ans =

5/2

>> % My problem is that, actually, i have more than 10 handle functions (lets say 10), and

>> % i do not want to write each one, every time. I want to copy them (from another software) and

>> % past in an array (in Matlab). And then, use this array as a source to call these 10 functions in the

>> % double "for loop".

>> % But i cannot make an array of 10 cells, including the 10 hundle functions. They comes

>> % out as "sym". And this, couse problem when i use it in the double "for loop". It gives me

>> % errors like : ........The following error occurred converting from sym to double:

% Error using symengine (line 59)

% DOUBLE cannot convert the input expression into a double array.

% If the input expression contains a symbolic variable, use VPA.

% Any help please

Answer 1

[Torsten]

f=@(t)[-7*t+25     %insert (by copy and paste), in the [ ], 10 functions. (Copy  %from another software)
    140*t+-122
    107*t+-56
    385*t+-890
    -546*t+2834
    -72*t+464
    -16*t+128
    440*t+-3064
    -256*t+2504
    -142*t+1478
    ];
result = integral(f,0,1,'ArrayValued',1);
C=zeros(2,1);
for kk=1:2
    for jj=1:2
        C(kk)=C(kk)+result(kk);
    end
end
C

C = 2×1

43.0000 -104.0000

[Kraka Doros]

Your answer, solve my question, and i have to accept it, as i will do.

But, as i told to Star Strider, i am thinking make my code more complicated, and i want, again help. If you have, time..

Here is what i want to add :

1. Like before, insert from another software 10 functions in an array f (to use them later in an integral, inside a double "for loop".
2. The integration of each of the 10 functions, want to be in different limits, follows by rule ,were d=number of functions in f, and kk=1:d
3. After i receive an array in which there will be the integrals of each 10 functions (to different limits, each one), lets say this array is

ArrayOf_Int

I want to use the "for loop" as like this (i am adding a product factor to each of the integrals) :

>> for kk=1:d

for jj=1:p

C(kk)=C(kk)+ArrayOf_Int(kk) * 2^jj;

end

end

here p can be any number i want, lets say 50.

Thanks for your help.

[Torsten]

f={@(t)-7*t+25     %insert (by copy and paste), in the [ ], 10 functions. (Copy  %from another software)
   @(t)140*t-122
   @(t)107*t-56
   @(t)385*t-890
   @(t)-546*t+2834
   @(t)-72*t+464
   @(t)-16*t+128
   @(t)440*t-3064
   @(t)-256*t+2504
   @(t)-142*t+1478
   };
d = size(f,1);
lb = (0:d-1).'/d;
ub = (1:d).'/d;
ArrayOf_Int = zeros(d,1);
for i = 1:d
  ArrayOf_Int(i) = integral(f{i},lb(i),ub(i));
end
ArrayOf_Int

ArrayOf_Int = 10×1

2.4650 -10.1000 -2.9250 -75.5250 258.8300 42.4400 11.7600 -273.4000 228.6400 134.3100

[Torsten]

f={@(t)-7*t+25     %insert (by copy and paste), in the [ ], 10 functions. (Copy  %from another software)
    @(t)140*t-122
    @(t)107*t-56
    @(t)385*t-890
    @(t)-546*t+2834
    @(t)-72*t+464
    @(t)-16*t+128
    @(t)440*t-3064
    @(t)-256*t+2504
    @(t)-142*t+1478
    };
d = size(f,1);
lb = (0:d-1).'/d;
ub = (1:d).'/d;
ArrayOf_Int = zeros(d,1);
for i = 1:d
    ArrayOf_Int(i) = integral(f{i},lb(i),ub(i));
end
C = 1.0;
jjfirst = 1;
jjlast = d;
expression = C*(4^(jjlast+1)-4^jjfirst)/3*sum(ArrayOf_Int)

expression = 4.4249e+08

[Kraka Doros]

Thanks