BinarySearchFunc.h File Reference

Functions for binary search of sorted Eigen Arrays. More...

#include <tuple>
#include <vector>
#include <Eigen/Dense>

Go to the source code of this file.

Namespaces
namespace	isce3
	base interpolator is an abstract base class

Typedefs
using	isce3::antenna::detail::tuple4i_t
using	isce3::antenna::detail::ArrayXui = Eigen::Array<Eigen::Index, Eigen::Dynamic, 1>

Functions
Eigen::Index	isce3::antenna::detail::bisect_left (const Eigen::Ref< const Eigen::ArrayXd > &x, double x0)
	Python-like bisect_left for an array sorted in ascending order.
Eigen::Index	isce3::antenna::detail::bisect_right (const Eigen::Ref< const Eigen::ArrayXd > &x, double x0)
	Python-like bisect_right for sorted array.
Eigen::Index	isce3::antenna::detail::locate_nearest (const Eigen::Ref< const Eigen::ArrayXd > &x, double x0)
	Locate the nearest neighbor to a value x0 in a sorted array x via binary search.
ArrayXui	isce3::antenna::detail::locate_nearest (const Eigen::Ref< const Eigen::ArrayXd > &x, const Eigen::Ref< const Eigen::ArrayXd > &x0)
	Locate the nearest neighbor to an array of values, x0, in a sorted array x via binary search.
tuple4i_t	isce3::antenna::detail::intersect_nearest (const Eigen::Ref< const Eigen::ArrayXd > &x1, const Eigen::Ref< const Eigen::ArrayXd > &x2)
	Intersect two sorted arrays x1 and x2 arrays to find the indices [first,last] for approximate overlap portion defined in terms of their nearest start/end values.

Detailed Description

Functions for binary search of sorted Eigen Arrays.

Typedef Documentation

tuple4i_t

using isce3::antenna::detail::tuple4i_t

Initial value:

 
        std::tuple<Eigen::Index, Eigen::Index, Eigen::Index, Eigen::Index>

Function Documentation

bisect_left()

Eigen::Index isce3::antenna::detail::bisect_left	(	const Eigen::Ref< const Eigen::ArrayXd > &	x,
		double	x0 )

Python-like bisect_left for an array sorted in ascending order.

Parameters

[in]	x	is a sorted array to be searched
[in]	x0	is the value to search for

Returns

first index to the array "x" where x[idx] >= x0

Note

The output will be limited to [0, x.size - 1] for out of range value.

bisect_right()

Eigen::Index isce3::antenna::detail::bisect_right	(	const Eigen::Ref< const Eigen::ArrayXd > &	x,
		double	x0 )

Python-like bisect_right for sorted array.

Parameters

[in]	x	is a sorted array to be searched
[in]	x0	is the value to search for

Returns

index to the array "x" where x[idx] > x0

Note

The output will be limited to [0, x.size - 1] for out of range value.

intersect_nearest()

tuple4i_t isce3::antenna::detail::intersect_nearest	(	const Eigen::Ref< const Eigen::ArrayXd > &	x1,
		const Eigen::Ref< const Eigen::ArrayXd > &	x2 )

Intersect two sorted arrays x1 and x2 arrays to find the indices [first,last] for approximate overlap portion defined in terms of their nearest start/end values.

Parameters

[in]	x1	is a sorted array
[in]	x2	is a sorted array

Returns

first index to array "x1"

last index (inclusive) to array "x1"

first index to array "x2"

last index (inclusive) to array "x2"

locate_nearest() [1/2]

ArrayXui isce3::antenna::detail::locate_nearest	(	const Eigen::Ref< const Eigen::ArrayXd > &	x,
		const Eigen::Ref< const Eigen::ArrayXd > &	x0 )

Locate the nearest neighbor to an array of values, x0, in a sorted array x via binary search.

Parameters

[in]	x	is a sorted array to be searched
[in]	x0	is the array of values to search for in "x"

Returns

Array of indices to the array "x" with the same size as that of x0.

Note

The indices will all be limited to within [0, x.size - 1].

locate_nearest() [2/2]

Eigen::Index isce3::antenna::detail::locate_nearest	(	const Eigen::Ref< const Eigen::ArrayXd > &	x,
		double	x0 )

Locate the nearest neighbor to a value x0 in a sorted array x via binary search.

Parameters

[in]	x	is a sorted array to be searched
[in]	x0	is the value to search for in "x"

Returns

index to the array "x" where abs(x[idx] - x0) is min.

Note

The output will be limited to [0, x.size - 1] for out of range value.