prod

prod(X)

If X is a vector, return the product of all the elements in X.

If X is a matrix, calculate the product of all the elements in each column of X and return a vector.

If X is a table, calculate the product of all the elements in each column of X and return a table.

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

For matrices and tables, DolphinDB's prod function always computes the product by column; NumPy flattens the array by default and computes the global product, unless you specify a dimension with the axis parameter. In addition, NumPy allows you to specify the axis parameter to calculate across multiple axes and specify initial to set the initial value.

X is a scalar/vector/matrix/table.

A numeric scalar, vector, matrix, or table.

prod(1 2 NULL 3);
// output: 6

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

prod(m);
// output: [6,120]