max

Syntax

max(X)

Arguments

X is a scalar/vector/matrix.

Y is an optional parameter, which can be a scalar, a vector of the same length as X or a matrix.

Details

For one input:

  • If X is a vector, return the maximum in X.

  • If X is a matrix, return a vector composed of the maximum in each column of X.

As with all aggregate functions, NULL values are not included in the calculation.

For two inputs:

  • If Y is a scalar, compare it with each element in X, replace the element in X with the larger value.

  • If Y and X are of the same type and length, compare the corresponding elements of them and return a vector containing each larger value.

Note: Before version 1.30.20/2.00.8, the function max compares the values of temporal types by converting them into LONG values;

Since version 1.30.20/2.00.8, DolphinDB has changed the handling of temporal types:

  • If X and Y are temporal scalars with different levels of time granularity, the coarser-grained value is converted to the finer granularity for comparison.

  • If X and/or Y is a vector, matrix, or table, the compared elements must be of the same temporal type.

Examples

$ max(1 2 3);
3

$ max(7.8 9 5.4);
9

$ (5 8 2 7).max();
8

$ m=matrix(1 2 3, 4 5 6);
$ m;

#0

#1

1

4

2

5

3

6

 
$ max(m);
[3,6]

$ max(m);
[3,6]

$ max(1 2 3, 2)
2 2 3

$ n = matrix(1 1 1, 5 5 5)
$ n;

#0

#1

1

5

1

5

1

5

 
$ max(m, n);

#0

#1

1

5

2

5

3

6

Related function: mmax