Data Conversion Rules

Java to MATLAB Conversion

The following table lists the data conversion rules for converting Java^® data types to MATLAB^® types.

Note: The conversion rules apply to scalars, vectors, matrices, and multidimensional arrays of the types listed.

The conversion rules apply not only when calling your own methods, but also when calling constructors and factory methods belonging to the MWArray classes.

When calling an MWArray class method constructor, supplying a specific data type causes the compiler to convert to that type instead of the default.

Java to MATLAB Conversion Rules

Java Type MATLAB Type

double

float

single

byte

int8

int

int32

short

int16

long

int64

char

boolean

logical

java.lang.Double

double

java.lang.Float

single

java.lang.Byte

int8

java.lang.Integer

int32

java.lang.Long

int64

java.lang.Short

int16

java.lang.Number

double

Note: Subclasses of java.lang.Number not listed above are converted to double.

java.lang.Boolean

logical

java.lang.Character

char

java.lang.String

char

Note: A Java string is converted to a 1-by-N array of char with N equal to the length of the input string.

An array of Java strings (String[]) is converted to an M-by-N array of char, with M equal to the number of elements in the input array and N equal to the maximum length of any of the strings in the array.

Higher dimensional arrays of String are converted similarly.

In general, an N-dimensional array of String is converted to an N+1 dimensional array of char with appropriate zero padding where supplied strings have different lengths.

MATLAB to Java Conversion

The following table lists the data conversion rules for converting MATLAB data types to Java types.

Note: The conversion rules apply to scalars, vectors, matrices, and multidimensional arrays of the types listed.

MATLAB to Java Conversion Rules

MATLAB Type Java Type (Primitive) Java Type (Object)

cell

Not applicable

Object

Note: Cell arrays are constructed and accessed as arrays of MWArray.

structure

Not applicable

Object

Note: Structure arrays are constructed and accessed as arrays of MWArray.

char char java.lang.Character

double double java.lang.Double

single float java.lang.Float

int8 byte java.lang.Byte

int16

short

java.lang.Short

int32 int java.lang.Integer

int64 long java.lang.Long

uint8

byte

java.lang.Byte

Java has no unsigned type to represent the uint8 used in MATLAB. Construction of and access to MATLAB arrays of an unsigned type requires conversion.

uint16

short

java.lang.short

Java has no unsigned type to represent the uint16 used in MATLAB. Construction of and access to MATLAB arrays of an unsigned type requires conversion.

uint32

int

java.lang.Integer

Java has no unsigned type to represent the uint32 used in MATLAB. Construction of and access to MATLAB arrays of an unsigned type requires conversion.

uint64

long

java.lang.Long

Java has no unsigned type to represent the uint64 used in MATLAB. Construction of and access to MATLAB arrays of an unsigned type requires conversion.

logical boolean java.lang.Boolean

Function handle Not supported

Java class Not supported

User class Not supported

Unsupported MATLAB Array Types

Java has no unsigned types to represent the uint8, uint16, uint32, and uint64 types used in MATLAB. Construction of and access to MATLAB arrays of an unsigned type requires conversion.

Was this topic helpful?

Documentation