# maxindc#

## Purpose#

Returns a column vector containing the index (i.e., row number) of the maximum element in each column of a matrix.

## Format#

y = maxindc(x)#
Parameters:

x (NxK matrix) – data

Returns:

y (Kx1 matrix) – contains the index of the maximum element in each column of x.

## Examples#

```// Generate random x matrix
x = round(rndn(4, 4)*5);

// Find maximum by column
mx = maxc(x);

// Find the indices of the maximums in each column
mxInd = maxindc(x);
```

If x is equal to:

```-2   -8   -1   -2
-1    9    0    7
9    0    4    8
-2    6    6    1
```

then

```     9            3
mx = 9    mxInd = 2
6            4
8            3
```

## Remarks#

If x is complex, `maxindc()` uses the complex modulus (`abs(x)`) to determine the largest elements.

To find the index of the maximum element in each row of a matrix, transpose the matrix before applying `maxindc()`.

To find the indices of the largest element in a matrix x, use:

```colInd = maxindc(maxc(x));
rowInd = maxindc(x[., colInd]);
```

If there are two or more “largest” elements in a column (i.e., two or more elements equal to each other and greater than all other elements), then `maxindc()` returns the index of the first one found, which will be the smallest index.