Isdouble (), issingle (), ..., functions are missing in Matlab2015a

Question

When I try:

>>isdouble(1)

I just get the error message

Undefined function or variable 'isdouble'.

The same for the other is * functions. But these are standard functions in Matlab, and I even find them when I use functions helpor doc:

>>help isdouble
isdouble - Determine whether input is double-precision data type

This MATLAB function returns 1 when the DataType property of fi object a is
double, and 0 otherwise.
...

So does anyone know what is going on here?

Answer 1

This is normal, since the MATLAB installation has no built-in functions by default isdouble(), issingle()etc. If you want to test the / handle value class, use the built-in isa(), as in:

isa(1, 'double');
isa('abc', 'char');

Answer 2

These functions are part of the toolbar : isa

isa(1, 'double');