Numeric Types

Integer and floating-point data

Numeric classes in MATLAB® include signed and unsigned integers, and single-precision and double-precision floating-point numbers. By default, MATLAB stores all numeric values as double-precision floating point. (You cannot change the default type and precision.) You can choose to store any number, or array of numbers, as integers or as single-precision. Integer and single precision arrays offer more memory-efficient storage than double precision.

All numeric types support basic array operations, such as indexing, reshaping, and mathematical operations.

Funktionen

alle erweitern

 double Double-precision arrays single Single-precision arrays int8 8-bit signed integer arrays int16 16-bit signed integer arrays int32 32-bit signed integer arrays int64 64-bit signed integer arrays uint8 8-bit unsigned integer arrays uint16 16-bit unsigned integer arrays uint32 32-bit unsigned integer arrays uint64 64-bit unsigned integer arrays
 cast Convert variable to different data type typecast Convert data type without changing underlying data
 isinteger Determine whether input is integer array isfloat Determine if input is floating-point array isnumeric Determine whether input is numeric array isreal Determine whether array uses complex storage isfinite Determine which array elements are finite isinf Determine which array elements are infinite isnan Determine which array elements are NaN
 eps Floating-point relative accuracy flintmax Largest consecutive integer in floating-point format Inf Create array of all Inf values intmax Largest value of specific integer type intmin Smallest value of specified integer type NaN Create array of all NaN values realmax Largest positive floating-point number realmin Smallest normalized floating-point number

Themen

Floating-Point Numbers

MATLAB represents floating-point numbers in either double-precision or single-precision format. The default is double precision.

Single Precision Math

This example shows how to perform arithmetic and linear algebra with single precision data.

Integers

MATLAB supports 1-, 2-, 4-, and 8-byte storage for integer data. If you use the smallest integer type that accommodates your data, you can save memory and program execution time.

Integer Arithmetic

This example shows how to perform arithmetic on integer data representing signals and images.

Create Complex Numbers

Create complex numbers. Complex numbers consist of a real part and an imaginary part.

Infinity and NaN

MATLAB represents infinity by the special value inf, and values that are neither real nor complex by the special value NaN, which stands for “Not a Number”.

Identifying Numeric Classes

You can check the data type of a variable using any of these commands.

Display Format for Numeric Values

Use the format function or set Preferences to control the display of numeric values.

Combining Unlike Integer Types

If you combine different integer types in a matrix (e.g., signed with unsigned, or 8-bit integers with 16-bit integers), all elements of the resulting matrix are given the data type of the leftmost element.

Combining Integer and Noninteger Data

If you combine integers with double, single, or logical classes, all elements of the resulting matrix are given the data type of the leftmost integer.

Empty Matrices

If you construct a matrix using empty matrix elements, the empty matrices are ignored in the resulting matrix.

Concatenation Examples

These examples show how to concatenate different data types.