redis - What are leading zeroes in regards to HyperLogLog? -

-

i reading antirez.com , wikipedia , other sources understang hll , how works, each time term "leading zeroes" used stumble. please explain means when talk hyperloglog.

leading zeroes number of 0s before first 1 in binary representation of hash. equivalent computing most significant bit.

hyperloglog algorithm not depend on computing these leading zeroes, needs check known prefix in binary representation of hash. happens computing significant bit fast on hardware implementations.


Comments

Post a Comment

Popular posts from this blog

ruby on rails - RuntimeError: Circular dependency detected while autoloading constant - ActiveAdmin.register Role -

-
i using activeadmin , have file doing this: activeadmin.register role something--- end however, server gives me error: runtimeerror: circular dependency detected while autoloading constant role /library/ruby/gems/2.0.0/gems/activesupport-4.0.10/lib/active_support/dependencies.rb:461:in `load_missing_constant' /library/ruby/gems/2.0.0/gems/activesupport-4.0.10/lib/active_support/dependencies.rb:184:in `const_missing' ~/desktop/boxfox/app/admin/role.rb:1:in `<top (required)>' /library/ruby/gems/2.0.0/gems/activesupport-4.0.10/lib/active_support/dependencies.rb:424:in `load' /library/ruby/gems/2.0.0/gems/activesupport-4.0.10/lib/active_support/dependencies.rb:424:in `block in load_file' /library/ruby/gems/2.0.0/gems/activesupport-4.0.10/lib/active_support/dependencies.rb:616:in `new_constants_in' /library/ruby/gems/2.0.0/gems/activesupport-4.0.10/lib/active_support/dependencies.rb:423:in `load_file' /library/ruby/gems/2.0.0/gems/activesuppor
Read more

c++ - OpenMP unpredictable overhead -

-
i have simple openmp code runs 4 empty threads , reports time: #include "omp.h" #include <sys/time.h> #include <cstdio> double start_time; void process_thread() { } int main(){ struct timeval tv; gettimeofday(&tv, null); start_time = 1000*((double)tv.tv_sec + 1e-6*(double)tv.tv_usec); printf("beginning time: %.3fms ",start_time-start_time); #pragma omp parallel schedule(static,1) for(int i=0;i<4;i++) process_thread(); gettimeofday(&tv, null); double cur_time = 1000*((double)tv.tv_sec + 1e-6*(double)tv.tv_usec); printf("finishing time: %.3fms\n\n",cur_time-start_time); } without openmp running time small , consistent: beginning time: 0.000ms finishing time: 0.050ms beginning time: 0.000ms finishing time: 0.050ms beginning time: 0.000ms finishing time: 0.049ms beginning time: 0.000ms finishing time: 0.049ms beginning time: 0.000ms finishing time: 0.050ms beginnin
Read more

javascript - Wordpress slider, not displayed 100% width -

-
so im making first wordpress theme scratch going fine got problem. want slider on homepage 1 thing wrong. im setting width of image 100% !important doesnt go 100% width. makes image wider not 100%. example here: http://bit.ly/11ouebg see image doesnt contain whole width. can see background-color. really weird, im using meteor slides. i hope can me out :d
Read more