Main Content

isa

Determine if input is instance of specified class

collapse all in page

Syntax

tf = isa(A,classname)
tf = isa(A,numericCategory)

Description

tf = isa(A,classname) returns 1 (true) if A is an instance of classname or a subclass of classname. Otherwise, it returns 0 (false). The input argument A can have any data type.

If A is an object, then isa returns 1 if dataType is either the class of A or a superclass of A.

example

tf = isa(A,numericCategory) returns 1 (true) if the data type of A belongs to the category specified by numericCategory. Otherwise, it returns 0 (false).

If A is an object, then isa returns 1 if the class of A, or any superclass of A, belongs to the specified category.

example

Examples

collapse all

Open Live Script

Create a numeric variable and determine if its data type is double.

A = 3.1416;
tf = isa(A,'double')
tf = logical
   1

Create an array of 32-bit integers and determine if its data type is int32.

A = int32([0 2 4 6 8])
A = 1x5 int32 row vector

   0   2   4   6   8


tf = isa(A,'int32')
tf = logical
   1

Determine if the data type of A is char.

tf = isa(A,'char')
tf = logical
   0
Open Live Script

Create an array whose data type is uint8. Determine if the array has a data type that belongs to the integer category.

A = uint8([0 2 4 6 8])
A = 1x5 uint8 row vector

   0   2   4   6   8


tf = isa(A,'integer')
tf = logical
   1

Determine if the data type of A belongs to the float category.

tf = isa(A,'float')
tf = logical
   0

Input Arguments

collapse all

Input array.

Class name, specified as a character vector or string scalar. classname can be the name of:

  • Any fundamental data type or MATLAB® class

  • A Java® or .NET class

The table shows the names of many commonly used MATLAB data types.

'half'Half-precision number
'single'Single-precision number
'double'Double-precision number
'int8'Signed 8-bit integer
'int16'Signed 16-bit integer
'int32'Signed 32-bit integer
'int64'Signed 64-bit integer
'uint8'Unsigned 8-bit integer
'uint16'Unsigned 16-bit integer
'uint32'Unsigned 32-bit integer
'uint64'Unsigned 64-bit integer
'logical'Logical 1 (true) or 0 (false)
'char'Character
'string'String array
'struct'Structure array
'cell'Cell array
'table'Table
'timetable'Timetable
'function_handle'Function handle

Data type category, specified as 'numeric', 'float', or 'integer'. These values represent categories of numeric types, as shown in the table.

'numeric'

Integer or floating-point array, having one of these data types:

  • double

  • single

  • half

  • int8

  • int16

  • int32

  • int64

  • uint8

  • uint16

  • uint32

  • uint64

'float'

Single- or double-precision floating-point array, having either of these data types:

  • double

  • single

  • half

'integer'

Signed or unsigned integer array, having one of these data types:

  • int8

  • int16

  • int32

  • int64

  • uint8

  • uint16

  • uint32

  • uint64

Tips

  • To test whether the input array is sparse, use the issparse function.

  • To test whether the input array has any imaginary or complex elements, use ~isreal(A).

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced before R2006a

See Also

| | | | |

Topics