integrating function from -inf to +inf

I'm trying to integrate the following function from -inf to +inf with repsect to x.

fun = @(x) -3.*v.^2 -4.*v.*a./((x.^2+a.^2)*pi) - a.^2./((x.^2+a.^2)^2*pi^2)

fun =

  function_handle with value:

    @(x)-3.*v.^2-4.*v.*a./((x.^2+a.^2)*pi)-a.^2./((x.^2+a.^2)^2*pi^2)

>> integral(fun,-inf,inf)
Error using symengine
Not a square matrix.

Error in sym/privBinaryOp (line 1030)
            Csym = mupadmex(op,args{1}.s, args{2}.s, varargin{:});

Error in  ^  (line 330)
        B = privBinaryOp(A, p, 'symobj::mpower');

Error in @(x)-3.*v.^2-4.*v.*a./((x.^2+a.^2)*pi)-a.^2./((x.^2+a.^2)^2*pi^2)

Error in integralCalc/iterateScalarValued (line 314)
                fx = FUN(t);

Error in integralCalc/vadapt (line 132)
            [q,errbnd] = iterateScalarValued(u,tinterval,pathlen);

Error in integralCalc (line 103)
        [q,errbnd] = vadapt(@minusInfToInfInvTransform,interval);

Error in integral (line 88)
Q = integralCalc(fun,a,b,opstruct);

I don't know why i'm getting this error?

by the way v and a are both constants

Answer 1

[Ameer Hamza]

You need use element-wise operator:

fun = @(x) -3.*v.^2 -4.*v.*a./((x.^2+a.^2)*pi) - a.^2./((x.^2+a.^2).^2*pi^2)
                                                                  %^ put a dot here

[Randy Chen]

Hi I just tried this, but I now have another error:

fun = @(x) -3.*v.^2 -4.*v.*a./((x.^2+a.^2)*pi) - a.^2./((x.^2+a.^2).^2*pi^2)

fun =

  function_handle with value:

    @(x)-3.*v.^2-4.*v.*a./((x.^2+a.^2)*pi)-a.^2./((x.^2+a.^2).^2*pi^2)

>> integral(fun,-inf,inf)
Error using integralCalc/finalInputChecks (line 522)
Input function must return 'double' or 'single' values. Found 'sym'.

Error in integralCalc/iterateScalarValued (line 315)
                finalInputChecks(x,fx);

Error in integralCalc/vadapt (line 132)
            [q,errbnd] = iterateScalarValued(u,tinterval,pathlen);

Error in integralCalc (line 103)
        [q,errbnd] = vadapt(@minusInfToInfInvTransform,interval);

Error in integral (line 88)
Q = integralCalc(fun,a,b,opstruct);

[Randy Chen]

i guess there's something wrong with my function in the first place?

[Steven Lord]

The integral function is for numeric integration. If you have fixed values for a and v, define variables with those values before creating your fun function. If you want to perform the integration symbolically use the int function on a symbolic expression (not a function handle.)

syms a x
f = a*x^2;
int(f, x, 0, 5)

a = 3;
f = @(x) a*x.^2;
integral(f, 0, 5)

[Randy Chen]

thank you!