MATLAB Function Reference

isa

Determine if input is object of given class

Syntax

• K = isa(obj, 'class_name')
  

Description

K = isa(obj, 'class_name') returns logical 1 (true) if obj is of class (or a subclass of) class_name, and logical 0 (false) otherwise.

The argument obj is a MATLAB object or a Java object. The argument class_name is the name of a MATLAB (predefined or user-defined) or a Java class. Predefined MATLAB classes include

logical	Logical array of true and false values
char	Characters array
numeric	Integer or floating-point array
integer	Signed or unsigned integer array
int8	8-bit signed integer array
uint8	8-bit unsigned integer array
int16	16-bit signed integer array
uint16	16-bit unsigned integer array
int32	32-bit signed integer array
uint32	32-bit unsigned integer array
int64	64-bit signed integer array
uint64	64-bit unsigned integer array
float	Single- or double-precision floating-point array
single	Single-precision floating-point array
double	Double-precision floating-point array
cell	Cell array
struct	Structure array
function_handle	Function handle
'class_name'	Custom MATLAB object class or Java class

To check for a sparse array, use issparse. To check for a complex array, use ~isreal.

Examples

• isa(rand(3,4),'double')
  ans =
      1
  

The following example creates an instance of the user-defined MATLAB class named polynom. The isa function identifies the object as being of the polynom class.

• polynom_obj = polynom([1 0 -2 -5]);
  isa(polynom_obj, 'polynom')
  ans =
       1
  

See Also

class, is*

is*

isappdata

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