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plus, +

Add numbers, append strings



C = A + B adds arrays A and B by adding corresponding elements. If one input is a string array, then plus appends the corresponding elements as strings.

The sizes of A and B must be the same or be compatible. If the sizes of A and B are compatible, then the two arrays implicitly expand to match each other. For example, if one of A or B is a scalar, then the scalar is combined with each element of the other array. Also, vectors with different orientations (one row vector and one column vector) implicitly expand to form a matrix.

C = plus(A,B) is an alternate way to execute A + B, but is rarely used. It enables operator overloading for classes.


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Create an array, A, and add a scalar value to it.

A = [0 1; 1 0];
C = A + 2
C = 2×2

     2     3
     3     2

The scalar value is added to each entry of A.

Create two 1-by-3 string arrays, then append similarly located strings in the arrays.

s1 = ["Red" "Blue" "Green"]
s1 = 1x3 string
    "Red"    "Blue"    "Green"

s2 = ["Truck" "Sky" "Tree"]
s2 = 1x3 string
    "Truck"    "Sky"    "Tree"

s = s1 + s2
s = 1x3 string
    "RedTruck"    "BlueSky"    "GreenTree"

Create two arrays, A and B, and add them together.

A = [1 0; 2 4];
B = [5 9; 2 1];
C = A + B
C = 2×2

     6     9
     4     5

The elements of A are added to the corresponding elements of B.

Create a 1-by-2 row vector and 3-by-1 column vector and add them.

a = 1:2;
b = (1:3)';
a + b
ans = 3×2

     2     3
     3     4
     4     5

The result is a 3-by-2 matrix, where each (i,j) element in the matrix is equal to a(j) + b(i):

a=[a1a2],b=[b1b2b3],          a+b=[a1+b1a2+b1a1+b2a2+b2a1+b3a2+b3].

Create an array, A, and add a column vector to it. The vector is treated as though it is a matrix of the same size as A, so that each element in the vector is added to a row in A.

A = [1 2 3; 4 5 6]
A = 2×3

     1     2     3
     4     5     6

b = [10; 100]
b = 2×1


A + b
ans = 2×3

    11    12    13
   104   105   106

Since R2023a

Create two tables and add them. The row names (if present in both) and variable names must be the same, but do not need to be in the same orders. Rows and variables of the output are in the same orders as the first input.

A = table([1;2],[3;4],VariableNames=["V1","V2"],RowNames=["R1","R2"])
A=2×2 table
          V1    V2
          __    __

    R1    1     3 
    R2    2     4 

B = table([4;2],[3;1],VariableNames=["V2","V1"],RowNames=["R2","R1"])
B=2×2 table
          V2    V1
          __    __

    R2    4     3 
    R1    2     1 

C = A + B
C=2×2 table
          V1    V2
          __    __

    R1    2     5 
    R2    5     8 

Input Arguments

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Operands, specified as scalars, vectors, matrices, multidimensional arrays, tables, or timetables. Inputs A and B must either be the same size or have sizes that are compatible (for example, A is an M-by-N matrix and B is a scalar or 1-by-N row vector). For more information, see Compatible Array Sizes for Basic Operations.

  • If one input is a string array, then the other input can be numeric, character, string, or a cell array. In this case, plus converts the non-string input into a string array and then appends corresponding elements of the inputs.

  • Operands with an integer data type cannot be complex.

  • If one input is a datetime array, duration array, or calendarDuration array, then numeric values in the other input are treated as a number of 24-hour days.

Inputs that are tables or timetables must meet the following conditions: (since R2023a)

  • If an input is a table or timetable, then all its variables must have data types that support the operation.

  • If only one input is a table or timetable, then the other input must be a numeric or logical array.

  • If both inputs are tables or timetables, then:

    • Both inputs must have the same size, or one of them must be a one-row table.

    • Both inputs must have variables with the same names. However, the variables in each input can be in a different order.

    • If both inputs are tables and they both have row names, then their row names must be the same. However, the row names in each input can be in a different order.

    • If both inputs are timetables, then their row times must be the same. However, the row times in each input can be in a different order.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | logical | char | string | datetime | duration | calendarDuration | table | timetable
Complex Number Support: Yes


  • For appending text, plus only operates on string arrays. Use the append function to append text in character vectors or cell arrays.

Extended Capabilities

GPU Code Generation
Generate CUDA® code for NVIDIA® GPUs using GPU Coder™.

Version History

Introduced before R2006a

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