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Function Reference: nanmax

statistics: v = nanmax (x)
statistics: v = nanmax (x, [], dim)
statistics: [v, idx] = nanmax (…)
statistics: v = nanmax (x, [], 'all')
statistics: v = nanmax (x, [], vecdim)
statistics: v = nanmax (x, y)

Find the maximum while ignoring NaN values.

v = nanmax (x) returns the maximum of x, after removing NaN values. If x is a vector, a scalar maximum value is returned. If x is a matrix, a row vector of column maxima is returned. If x is a multidimentional array, the nanmax operates along the fisrt nonsigleton dimension. If all values in a column are NaN, the maximum is returned as NaN rather than [].

v = nanmax (x, [], dim) operates along the dimension dim of x.

[v, idx] = nanmax (…) also returns the row indices of the maximum values for each column in the vector idx. When x is a vector, then idx is a scalar value as v.

v = nanmax (x, [], 'all') returns the maximum of all elements of x, after removing NaN values. It is the equivalent of nanmax (x(:)). The optional flag 'all' cannot be used together with dim or vecdim input arguments.

v = nanmax (x, [], vecdim) returns the maximum over the dimensions specified in the vector vecdim. Each element of vecdim represents a dimension of the input array x and the output v has length 1 in the specified operating dimensions. The lengths of the other dimensions are the same for x and y. For example, if x is a 2-by-3-by-4 array, then nanmax (x, [1 2]) returns a 1-by-1-by-4 array. Each element of the output array is the maximum of the elements on the corresponding page of x. If vecdim indexes all dimensions of x, then it is equivalent to nanmax (x, 'all'). Any dimension in vecdim greater than ndims (x) is ignored.

See also: max, nanmin, nansum

Source Code: nanmax

Example: 1

  

 ## Find the column maximum values and their indices
 ## for matrix data with missing values.

 x = magic (3);
 x([1, 6:9]) = NaN
 [y, ind] = nanmax (x)

x =

   NaN     1   NaN
     3     5   NaN
     4   NaN   NaN

y =

     4     5   NaN

ind =

   3   2   1

Example: 2

  

 ## Find the maximum of all the values in an array, ignoring missing values.
 ## Create a 2-by-5-by-3 array x with some missing values.

 x = reshape (1:30, [2, 5, 3]);
 x([10:12, 25]) = NaN

 ## Find the maximum of the elements of x.

 y = nanmax (x, [], 'all')

x =

ans(:,:,1) =

     1     3     5     7     9
     2     4     6     8   NaN

ans(:,:,2) =

   NaN    13    15    17    19
   NaN    14    16    18    20

ans(:,:,3) =

    21    23   NaN    27    29
    22    24    26    28    30

y = 30