vertcat

Concatenate arrays vertically

Description

example

C = vertcat(A,B) concatenates B vertically to the end of A when A and B have compatible sizes (the lengths of the dimensions match except in the first dimension).

example

C = vertcat(A1,A2,…,An) concatenates A1, A2, … , An vertically.

vertcat is equivalent to using square brackets for vertically concatenating arrays. For example, [A; B] is equal to vertcat(A,B) when A and B are compatible arrays.

Examples

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Create two matrices and concatenate them vertically, first by using square bracket notation, and then by using vertcat.

A = [1 2 3; 4 5 6]
A = 2×3

     1     2     3
     4     5     6

B = [7 8 9]
B = 1×3

     7     8     9

C = [A; B]
C = 3×3

     1     2     3
     4     5     6
     7     8     9

D = vertcat(A,B)
D = 3×3

     1     2     3
     4     5     6
     7     8     9

Create a table A with three rows and five variables.

A = table([5;6;5],['M';'M';'M'],[45;41;40],[45;32;34],{'NY';'CA';'MA'},...
    'VariableNames',{'Age' 'Gender' 'Height' 'Weight' 'Birthplace'},...
    'RowNames',{'Thomas' 'Gordon' 'Percy'})
A=3×5 table
              Age    Gender    Height    Weight    Birthplace
              ___    ______    ______    ______    __________

    Thomas     5       M         45        45        {'NY'}  
    Gordon     6       M         41        32        {'CA'}  
    Percy      5       M         40        34        {'MA'}  

Create a table B with the same variables as A except for order.

B = table(['F';'M';'F'],[6;6;5],{'AZ';'NH';'CO'},[31;42;33],[39;43;40],...
    'VariableNames',{'Gender' 'Age' 'Birthplace' 'Weight' 'Height'})
B=3×5 table
    Gender    Age    Birthplace    Weight    Height
    ______    ___    __________    ______    ______

      F        6       {'AZ'}        31        39  
      M        6       {'NH'}        42        43  
      F        5       {'CO'}        33        40  

Vertically concatenate tables A and B. The variables of C are in the same order as the variables of A and default row names are used for the rows from B.

C = vertcat(A,B)
C=6×5 table
              Age    Gender    Height    Weight    Birthplace
              ___    ______    ______    ______    __________

    Thomas     5       M         45        45        {'NY'}  
    Gordon     6       M         41        32        {'CA'}  
    Percy      5       M         40        34        {'MA'}  
    Row4       6       F         39        31        {'AZ'}  
    Row5       6       M         43        42        {'NH'}  
    Row6       5       F         40        33        {'CO'}  

Concatenate a date character vector, a string date, and a datetime into a single column of dates. The result is a datetime column vector.

chardate = '2016-03-24';
strdate = "2016-04-19";
t = datetime('2016-05-10','InputFormat','yyyy-MM-dd');
C = vertcat(chardate,strdate,t)
C = 3x1 datetime array
   24-Mar-2016
   19-Apr-2016
   10-May-2016

Concatenate three string arrays into a single array.

A1 = ["str1" "str2"];
A2 = ["str3" "str4"];
A3 = ["str5" "str6"];
C = vertcat(A1,A2,A3)
C = 3x2 string array
    "str1"    "str2"
    "str3"    "str4"
    "str5"    "str6"

Create a cell array containing two matrices. Vertically concatenate the matrices from the cell array into one matrix.

M1 = [1 2; 3 4];
M2 = [5 6; 7 8];
A1 = {M1,M2};
C = vertcat(A1{:})
C = 4×2

     1     2
     3     4
     5     6
     7     8

Input Arguments

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First input, specified as a scalar, vector, matrix, multidimensional array, table, or timetable.

Second input, specified as a scalar, vector, matrix, multidimensional array, table, or timetable.

  • The elements of B are concatenated to the end of the first input along the first dimension. The sizes of the input arguments must be compatible. For example, if the first input is a matrix of size 3-by-2, then B must have 2 columns.

  • You can concatenate valid combinations of different types. For more information, see Valid Combinations of Unlike Classes.

List of inputs, specified as a comma-separated list of elements to concatenate in the order they are specified.

  • The inputs must have compatible sizes. For example, if A1 is a row vector of length m, then the remaining inputs must each have m columns to concatenate vertically.

  • You can concatenate valid combinations of different types. For more information, see Valid Combinations of Unlike Classes.

Algorithms

When concatenating an empty array to a nonempty array, vertcat omits the empty array in the output. For example, vertcat([1; 2],[]) returns the column vector [1; 2].

If all input arguments are empty and have compatible sizes, then vertcat returns an empty array whose size is equal to the output size as when the inputs are nonempty. For example, vertcat(zeros(1,0),zeros(2,0)) returns a 3-by-0 empty array. If the input sizes are not compatible, then vertcat returns a 0-by-0 empty array.

Extended Capabilities

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

Introduced before R2006a