Numeric

This module provides simple numeric routines in Lua.

halmd.numeric.sum(t)

Compute the sum of the indexed elements of a table.

Parameters:t (table) – input table Returns:sum over all indexed elements in t

halmd.numeric.prod(t)

Compute the product of the indexed elements of a table.

Parameters:t (table) – input table Returns:product over all indexed elements in t

halmd.numeric.find_comp(t, comp)

Find the last value of a table that satisfies comp(a,b)

Parameters:

• t (table) – input table
• comp – callable that takes two elements of t and returns true or false

Returns:

last element in t that satisfied comp(a,b)

halmd.numeric.max(t)

Find the maximum value in a table

Parameters:t (table) – input table Returns:maximum value in t

halmd.numeric.min(t)

Find the minimum value in a table

Parameters:t (table) – input table Returns:minmum value in t

halmd.numeric.scalar_vector(size, value)

Create vector of given size with scalar value

Parameters:

• size (number) – number of elements
• value – value for each element of the vector

Returns:

vector of length with each element set to value

halmd.numeric.scalar_matrix(rows, columns, value)

Create matrix of given size with scalar value

Parameters:

• rows (number) – number of rows
• columns (number) – number of columns
• value – value for each element of the matrix

Returns:

matrix of dimension with each element set to value

halmd.numeric.trans(m)

Calculate transpose of matrix

Parameters:m (matrix) – input matrix Returns:transpose of m

halmd.numeric.diag(m)

Return diagonal elements of n×n matrix

Parameters:m (matrix) – input square matrix Returns:table of diagonal elements of m

halmd.numeric.offset_to_multi_index(offset, dims)

Convert one-dimensional offset to multi-dimensional index

Assumes contiguous storage of the array data in row-major order.

Parameters:

• offset (number) – 1-based one-dimensional offset
• dims (table) – dimensions (shape) of multi-dimensional array

Returns:

1-based multi-dimensional index of array element at offset

halmd.numeric.multi_index_to_offset(index, dims)

Convert multi-dimensional index to one-dimensional offset

Assumes contiguous storage of the array data in row-major order.

Parameters:

• index (table) – 1-based multi-dimensional index
• dims (table) – dimensions (shape) of multi-dimensional array

Returns:

1-based offset of array element at index