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4.4 Integer Data Types
Octave supports integer matrices as an alternative to using double precision. It is possible to use both signed and unsigned integers represented by 8, 16, 32, or 64 bits. It should be noted that most computations require floating point data, meaning that integers will often change type when involved in numeric computations. For this reason integers are most often used to store data, and not for calculations.
In general most integer matrices are created by casting existing matrices to integers. The following example shows how to cast a matrix into 32 bit integers.
float = rand (2, 2) ⇒ float = 0.37569 0.92982 0.11962 0.50876 integer = int32 (float) ⇒ integer = 0 1 0 1 
As can be seen, floating point values are rounded to the nearest integer when converted.
 Builtin Function: isinteger (x)
Return true if x is an integer object (int8, uint8, int16, etc.). Note that
isinteger (14)
is false because numeric constants in Octave are double precision floating point values.
 Builtin Function: intmax (type)
Return the largest integer that can be represented in an integer type. The variable type can be

int8
signed 8bit integer.

int16
signed 16bit integer.

int32
signed 32bit integer.

int64
signed 64bit integer.

uint8
unsigned 8bit integer.

uint16
unsigned 16bit integer.

uint32
unsigned 32bit integer.

uint64
unsigned 64bit integer.
The default for type is
uint32
.
 Builtin Function: intmin (type)
Return the smallest integer that can be represented in an integer type. The variable type can be

int8
signed 8bit integer.

int16
signed 16bit integer.

int32
signed 32bit integer.

int64
signed 64bit integer.

uint8
unsigned 8bit integer.

uint16
unsigned 16bit integer.

uint32
unsigned 32bit integer.

uint64
unsigned 64bit integer.
The default for type is
uint32
.
 Function File: intwarning (action)
 Function File: intwarning (s)
 Function File: s = intwarning (…)
Control the state of the warning for integer conversions and math operations.
 "query"
The state of the Octave integer conversion and math warnings is queried. If there is no output argument, then the state is printed. Otherwise it is returned in a structure with the fields "identifier" and "state".
intwarning ("query") The state of warning "Octave:intconvertnan" is "off" The state of warning "Octave:intconvertnonintval" is "off" The state of warning "Octave:intconvertoverflow" is "off" The state of warning "Octave:intmathoverflow" is "off"
 "on"
Turn integer conversion and math warnings "on". If there is no output argument, then nothing is printed. Otherwise the original state of the state of the integer conversion and math warnings is returned in a structure array.
 "off"
Turn integer conversion and math warnings "on". If there is no output argument, then nothing is printed. Otherwise the original state of the state of the integer conversion and math warnings is returned in a structure array.
The original state of the integer warnings can be restored by passing the structure array returned by
intwarning
to a later call tointwarning
. For examples = intwarning ("off"); … intwarning (s);
See also: warning.
4.4.1 Integer Arithmetic 
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