aconcat

Purpose

Concatenates conformable matrices and arrays in a user-specified dimension.

Format

y = aconcat(a, b, dim)
Parameters:
  • a (matrix or N-dimensional array.) –
  • b (matrix or K-dimensional array) – conformable with a.
  • dim (scalar) – dimension in which to concatenate.
Returns:

y (N-dimensional array) – the result of the concatenation.

Examples

// Create a 2x3x4 array with each element set to 0
a = arrayinit(2|3|4,0);

// Create a 3x4 matrix with each element set to 3
b = 3*ones(3, 4);
y = aconcat(a, b, 3);

y will be a 3x3x4 array, where [1,1,1] through [2,3,4] are zeros and [3,1,1] through [3,2,4] are threes.

/*
** Create an additive sequence from 1-20 and 'reshape' it
** into a 4x5 matrix
*/
a = reshape(seqa(1, 1, 20), 4, 5);

b = zeros(4, 5);
y = aconcat(a, b, 3);

y will be a 2x4x5 array, where [1,1,1] through [1,4,5] are sequential integers beginning with 1, and [2,1,1] through [2,4,5] are zeros.

/*
** The pipe operator '|' causes vertical concatenation so
** that the statement 2|3|4 creates a 3x1 column vector
** equal to { 2, 3, 4 }
*/
a = arrayinit(2|3|4,0);
b = seqa(1, 1, 24);

// 'Reshape' the vector 'b' into a 2x3x4 dimensional array
b = areshape(b,2|3|4);
y = aconcat(a, b, 5);

y will be a 2x1x2x3x4 array, where [1,1,1,1,1] through [1,1,2,3,4] are zeros, and [2,1,1,1,1] through [2,1,2,3,4] are sequential integers beginning with 1.

a = arrayinit(2|3|4, 0);
b = seqa(1, 1, 6);
b = areshape(b, 2|3|1);
y = aconcat(a, b, 1);
print "y = " y;

y will be a 2x3x5 array:

y =

Plane [1,.,.]

0.00     0.00     0.00     0.00      1.0
0.00     0.00     0.00     0.00      2.0
0.00     0.00     0.00     0.00      3.0

Plane [2,.,.]

0.00     0.00     0.00     0.00      4.0
0.00     0.00     0.00     0.00      5.0
0.00     0.00     0.00     0.00      6.0

Remarks

a and b are conformable if all dimensions other than the dimension specified by dim have the same sizes.

If a or b is a matrix, then the size of dimension 1 is the number of columns in the matrix, and the size of dimension 2 is the number of rows in the matrix.

See also

Functions areshape()