Error when using integral function on exponential integration

 function = @(x) (exp(x)/x);
 y = integral(function,3.5,4.5);

Answer 1

[Geoff Hayes]

Athul - the error message is

 function = @(x) (exp(x)/x);
 Error: Function definitions are not permitted in this context.

The keyword function should be considered reserved for defining functions in your m-files and not for anonymous functions. Try using something else instead. For example,

 myFunc = @(x) (exp(x)/x);
 y = integral(myFunc,3.5,4.5);

You will get a different error with the above

 Error using integralCalc/finalInputChecks (line 515)
 Output of the function must be the same size as the input. If FUN is an array-valued  
 integrand, set the 'ArrayValued' option to true

When using integral, an array of elements will be passed into your anonymous function, so x will be an array. Adjust your definition to

myFunc = @(x) (exp(x)./x);

so that an element-wise division occurs.