Miscellaneous convenience resources. More...

#include <tuple>
#include <vector>
#include <string>
#include <memory>
#include <limits>
#include <algorithm>
#include <iostream>
#include <cstdlib>
#include <cmath>
#include <ctime>
#include <boost/math/common_factor.hpp>
#include <boost/algorithm/string.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/tokenizer.hpp>
#include <boost/mpi.hpp>
#include <constants.hpp>
#include <Eigen/Dense>
#include <Eigen/Sparse>
#include <unsupported/Eigen/Splines>

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Classes
class	alma::Container_comparator< T >
	Comparator function object template for a container of comparable objects. More...

class	alma::Min_keeper< T >
	Convenience class for updating a minimum value and keeping track of all the objects associated to it. More...

Functions
template<typename T , typename... Args>
std::unique_ptr< T >	alma::make_unique (Args &&... args)
	Emulation of C++14's make_unique.

template<typename T >
std::tuple< std::vector< typename T::key_type >, std::vector< typename T::mapped_type > >	alma::split_keys_and_values (const T &input)
	Put the keys and values of a map (or similar) into separate vectors. More...

void	alma::flush_istream (std::istream &f)
	Read from f until ' ' is found. More...

template<typename T >
std::vector< T >	alma::tokenize_homogeneous_line (std::string &line, const std::string sep=" \)
	Try to tokenize a line into homogeneous tokens. More...

bool	alma::starts_with_character (const std::string &line, const std::string &chars)
	Check whether a line starts with a character from a given set. More...

bool	alma::almost_equal (const double a, const double b, const double abstol=1e-8, const double reltol=1e-5)
	Approximate comparation between doubles. More...

double	alma::ssqrt (double x)
	"Signed square root" of real numbers, that converts purely imaginary numbers to negative values. More...

template<typename T >
int	alma::signum (const T &arg)
	Compute the sign of an argument. More...

std::string	alma::get_timestamp ()
	Build a timestamp in our preferred format. More...

std::array< std::size_t, 2 >	alma::my_jobs (std::size_t njobs, std::size_t nprocs, std::size_t my_id)
	Compute the minimum and maximum indices of the jobs that must be executed in the current process. More...

template<typename T , typename U >
U	alma::python_mod (const T &n, const U &d)
	Alternative modulus operation with a behavior similar to the % operator in Python. More...

double	alma::bose_einstein (double omega, double T)
	Bose-Einstein distribution. More...

double	alma::bose_einstein_kernel (double omega, double T)
	Integration kernel for the specific heat, thermal conductivity and other integrals. More...

Eigen::VectorXi	alma::reduce_integers (const Eigen::Ref< const Eigen::VectorXi > &vector)
	Divide a vector of integers by the GCD of their coefficients. More...

std::string	alma::engineer_format (double x, bool insert_space=false)
	Convert a numerical value to a string that uses engineering prefix.

Eigen::VectorXd	alma::logSpace (double min, double max, int N)
	Construct a vector with N logarithmically spaced values from min to max. More...

Eigen::VectorXd	alma::splineInterpolation (const Eigen::Ref< const Eigen::VectorXd > &X, const Eigen::Ref< const Eigen::VectorXd > &Y, const Eigen::Ref< const Eigen::VectorXd > &Xtarget)
	Perform spline interpolation of a tabulated function Y(X) at Xtarget. More...

Eigen::VectorXd	alma::linearInterpolation (const Eigen::Ref< const Eigen::VectorXd > &X, const Eigen::Ref< const Eigen::VectorXd > &Y, const Eigen::Ref< const Eigen::VectorXd > &Xtarget)
	Perform linear interpolation of a tabulated function Y(X) at Xtarget. More...

template<class Archive , typename S >
void	boost::serialization::save (Archive &ar, const Eigen::Triplet< S > &t, const unsigned int version)
	Allow boost to serialize an Eigen::Triplet.

template<class Archive , typename S >
void	boost::serialization::load (Archive &ar, Eigen::Triplet< S > &t, const unsigned int version)
	Allow boost to unserialize an Eigen::Triplet.

template<class Archive , typename S >
void	boost::serialization::serialize (Archive &ar, Eigen::Triplet< S > &t, const unsigned int version)
	Dummy function allowing us to implement save() and load() separately. More...

Detailed Description

Miscellaneous convenience resources.

Function Documentation

◆ almost_equal()

bool alma::almost_equal	(	const double	a,
		const double	b,
		const double	abstol = `1e-8`,
		const double	reltol = `1e-5`
	)

inline

Approximate comparation between doubles.

Parameters

[in]	a	- first value
[in]	b	- second value
[in]	abstol	- Maximum absolute tolerance
[in]	reltol	- Maximum relative tolerance

Returns: - true if the two values are almost equal

◆ bose_einstein()

double alma::bose_einstein	(	double	omega,
		double	T
	)

inline

Bose-Einstein distribution.

Parameters

[in]	omega	- angular frequency in rad/ps
[in]	T	- temperature in K

Returns: the average occupation number at equilibrium

◆ bose_einstein_kernel()

double alma::bose_einstein_kernel	(	double	omega,
		double	T
	)

inline

Integration kernel for the specific heat, thermal conductivity and other integrals.

This function implements the calculation of (x / sinh(x))^2, where x = hbar * omega / (2 * kB *T).

Parameters

[in]	omega	- angular frequency in rad/ps
[in]	T	- temperature in K

Returns: the value of the aforementioned function

◆ flush_istream()

void alma::flush_istream ( std::istream & f )

inline

Read from f until '
' is found.

This function is meant to be called after reading data from f using >> and before using std::getline() on it.

Parameters

[in] f - istream from which to read

◆ get_timestamp()

std::string alma::get_timestamp ( )

inline

Build a timestamp in our preferred format.

Returns: a string containing the current time.

◆ linearInterpolation()

Eigen::VectorXd alma::linearInterpolation	(	const Eigen::Ref< const Eigen::VectorXd > &	X,
		const Eigen::Ref< const Eigen::VectorXd > &	Y,
		const Eigen::Ref< const Eigen::VectorXd > &	Xtarget
	)

inline

Perform linear interpolation of a tabulated function Y(X) at Xtarget.

X must be strictly ascending (no duplicate entries).

◆ logSpace()

Eigen::VectorXd alma::logSpace	(	double	min,
		double	max,
		int	N
	)

inline

Construct a vector with N logarithmically spaced values from min to max.

◆ my_jobs()

std::array<std::size_t, 2> alma::my_jobs	(	std::size_t	njobs,
		std::size_t	nprocs,
		std::size_t	my_id
	)

inline

Compute the minimum and maximum indices of the jobs that must be executed in the current process.

Split njobs jobs among nproc processes and return the minimum and maximum indices of the jobs that must be assigned to the current process, bundled in an array. More specifically, return jmin and jmax so that we can write a for loop like for (auto j = jmin; j < jmax; ++j)

Parameters

[in]	njobs	- number of jobs
[in]	nprocs	- number of process
[in]	my_id	- id of the current process

◆ python_mod()

template<typename T , typename U >

U alma::python_mod	(	const T &	n,
		const U &	d
	)

inline

Alternative modulus operation with a behavior similar to the % operator in Python.

Parameters

[in]	n	- numerator
[in]	d	- denominator

Returns: the remainder of the integer division n / d with the same sign as d.

◆ reduce_integers()

Eigen::VectorXi alma::reduce_integers ( const Eigen::Ref< const Eigen::VectorXi > & vector )

inline

Divide a vector of integers by the GCD of their coefficients.

Parameters

[in] vector - the original vector

Returns: the reduced vector

◆ serialize()

template<class Archive , typename S >

void boost::serialization::serialize	(	Archive &	ar,
		Eigen::Triplet< S > &	t,
		const unsigned int	version
	)

Dummy function allowing us to implement save() and load() separately.

◆ signum()

template<typename T >

int alma::signum ( const T & arg )

inline

Compute the sign of an argument.

Parameters

[in] arg - anything that can be constructed passing 0 as the only argument and that supports operator -

Returns: -1, 0 or 1 depending on the sign of arg

◆ splineInterpolation()

Eigen::VectorXd alma::splineInterpolation	(	const Eigen::Ref< const Eigen::VectorXd > &	X,
		const Eigen::Ref< const Eigen::VectorXd > &	Y,
		const Eigen::Ref< const Eigen::VectorXd > &	Xtarget
	)

inline

Perform spline interpolation of a tabulated function Y(X) at Xtarget.

◆ split_keys_and_values()

template<typename T >

std::tuple<std::vector<typename T::key_type>, std::vector<typename T::mapped_type> > alma::split_keys_and_values ( const T & input )

Put the keys and values of a map (or similar) into separate vectors.

◆ ssqrt()

double alma::ssqrt ( double x )

inline

"Signed square root" of real numbers, that converts purely imaginary numbers to negative values.

Parameters

[in] x - argument of the square root

Returns: a real number with the absolute value of sqrt(|x|) and the sign of x

◆ starts_with_character()

bool alma::starts_with_character	(	const std::string &	line,
		const std::string &	chars
	)

inline

Check whether a line starts with a character from a given set.

Parameters

[in]	line	- string containing the line
[in]	chars	- string containing the set of characters

Returns: true if line starts with a character from chars

◆ tokenize_homogeneous_line()

template<typename T >

std::vector<T> alma::tokenize_homogeneous_line	(	std::string &	line,
		const std::string	sep = `" \t"`
	)

inline

Try to tokenize a line into homogeneous tokens.

This function tries to split a line into fields that can all be cast into the same type and return a vector of tokens. boost::bad_lexical_cast will be thrown in case of failure.

Parameters

[in]	line	- line of text to tokenize
[in]	sep	- field separators

Returns: a vector of tokens

Classes

Functions

Detailed Description

Function Documentation

◆ almost_equal()

◆ bose_einstein()

◆ bose_einstein_kernel()

◆ flush_istream()

◆ get_timestamp()

◆ linearInterpolation()

◆ logSpace()

◆ my_jobs()

◆ python_mod()

◆ reduce_integers()

◆ serialize()

◆ signum()

◆ splineInterpolation()

◆ split_keys_and_values()

◆ ssqrt()

◆ starts_with_character()

◆ tokenize_homogeneous_line()