ISA ISA Test Type of Variable Usage Tests the type of a variable. The syntax for its use is 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 - 'float' for 32-bit floating point numbers - 'double' for 64-bit floating point numbers - 'complex' for complex floating point numbers with 32-bits per field - 'dcomplex' for complex floating point numbers with 64-bits per field - 'string' for string arrays If the argument is a user-defined type (via the class function), then the name of that class is returned.