filevector v 0.0-7

filevector is (c) 2018 Yurii Aulchenko, EMCR, Lennart C. Karssen

filevector is distributed under GNU GPL v 2.0 or later

filevector is a class for working with large arrays of variables,
the key features are fast access to variables and low RAM 
consumption

--------------------- IMPORTANT NOTICE ---------------------
Early 2018, PolyOmica, the main sponsor of the GenABEL project announced 
that it would discontinue its support. As PolyOmica was our only sponsor, 
we regretfully have to announce the likely discontinuation of the GenABEL 
Project in its current form, unless a new sponsor steps up or someone 
takes over maintenance and futher development of (some of) the tools. 
----------------------------------------------------------

most useful API functions are:

void initilise_empty_file(char * filename, unsigned long int nvariables, unsigned long int nobservations, unsigned short int type);

	creates empty filevector file (you can fill that later on using "write"-functions)

filevector my_filevector;

	creates an filevector object (not yet connected to a file);

myfilevector.initialize(char * filename, unsigned long int cachesizeMb);
	
	connects the object to the fvf-file "filename" using "cachesizeMb" 
	Mb of cache recommendation: for most systems 2048 provides maximum 
	speed; however as little as 256 gives very good performance still
	value "0" is possible -- one variable at a time

void read_variable(unsigned long int nvar, DT * outvec);

	reads variable "nvar" to "outvec", updating cache 
	starting with "nvar" if "nvar" is not in cache

void write_variable(unsigned long int nvar, DT * datavec);

	writes variable "nvar" to "outvec"

DT read_element(unsigned long int nvar, unsigned long int nobs);

	reads an element "nobs" from variable "nvar"; this function 
	reads directly from file withput updating cache
	
void write_element(unsigned long int nvar, unsigned long int nobs, DT data);

	writes an element "nobs" from variable "nvar"
	

Read frvector.h for more info