Section: Inspection Functions
y = isa(x,type)
where x is the variable to test, and type is
the type.  Supported built-in types are
'cell' for cell-arrays
 'struct' for structure-arrays
 'logical' for logical arrays
 'uint8' for unsigned 8-bit integers
 'int8' for signed 8-bit integers
 'uint16' for unsigned 16-bit integers
 'int16' for signed 16-bit integers
 'uint32' for unsigned 32-bit integers
 'int32' for signed 32-bit integers
 'uint64' for unsigned 64-bit integers
 'int64' for signed 64-bit integers
 'single' for 32-bit floating point numbers
 'double' for 64-bit floating point numbers
 'char' for string arrays
 class function), then
the name of that class is returned.
isa call.
--> a = {1}
a = 
 [1] 
--> isa(a,'char')
ans = 
 0 
--> isa(a,'cell')
ans = 
 1 
Here we use isa along with shortcut boolean evaluation to 
safely determine if a variable contains the string 'hello'
--> a = 'hello' a = hello --> isa(a,'char') && strcmp(a,'hello') ans = 1