I'm not sure why MIN_COMMON_WORDS is declared in Database.h and not the cpp file? Maybe the intention is that the library user could change this value programmatically like a parameter. This will however not work, since the the nature of static variables is that they are independent in each translation unit, so setting it from your program code will not affect the value in Database.cpp.
This is probably also the reason why you get a compiler warning like
/usr/wiss/demmeln/work/slam/ldso/LDSO/thirdparty/DBoW3/src/Database.h:31:12: warning: ‘DBoW3::MIN_COMMON_WORDS’ defined but not used [-Wunused-variable]
static int MIN_COMMON_WORDS = 5;
every time you include Database.h.
Solution? If you want a configurable parameter, you might want to add it to the Database class as a member. If you want a constant, make it static const or else move it to the cpp file.
I'm not sure why
MIN_COMMON_WORDSis declared inDatabase.hand not thecppfile? Maybe the intention is that the library user could change this value programmatically like a parameter. This will however not work, since the the nature of static variables is that they are independent in each translation unit, so setting it from your program code will not affect the value inDatabase.cpp.This is probably also the reason why you get a compiler warning like
every time you include
Database.h.Solution? If you want a configurable parameter, you might want to add it to the Database class as a member. If you want a constant, make it
static constor else move it to thecppfile.