positive and negative infinity for integral types in c++ -


i reading positive , negative infinity in c++.

i read integral types dont have infinite value ie. std::numeric_limits<int>::infinity(); wont work, std::numeric_limits<int>::max(); work , represent maximum possible value can represented integral type.

so std::numeric_limits<int>::max(); of integral type taken positive infinite limit ?

or integral type has max value , infinity value not true ?

floating point numbers have special bit pattern indicate "the value infinity", used when result of operation defined infinite.

integer values have set number of bits, , bits used represent numeric value. there no "special bit pattern", it's whatever sum of bit positions mean.

edit: on page 315 of hardcopy of amd64 architecture programmer's manual, says

infinity. infinity positve or negative number +∞ , -∞, in integer bit 1, biased exponent maximum , fraction 0. infintes maximum numbers can represented in floating point format, negative infinity less finite number , positive infinity greater finite number (ie. affine sense).

and infinite result produce when non-zero, non-infinite number divided 0 or multiplied infinity, or when infinity added infinity or 0. arithmetic infinites exact. example, adding floating point number +∞ gives result of +∞ arithmetic comparisons work correctly on infinites. exceptions occur when use of infinity source operand constitutes invalid operation.

(any typing mistakes mine)


Comments

Post a Comment

Popular posts from this blog

Eclipse formatter for java ending braces -

i know if it's possible setup eclipse format braces using banner style. we're working code uses banner style formatting , keep consistent within team version control reasons. here's example of banner style formatting not familiar: public class foo { //------------------------ public static void main (string[] args) { boolean condition = true; try { if (condition) { system.out.println ("condition true"); } else system.out.println ("not condition"); } catch (exception ex) { // handle errors } } //------------------------ } update: name style ratliff. experiment java->code style->formatter preferences. "banner style" seems poor use of space given outline view , quick outline functionality.
Read more

ruby - Nesting modules inside of a Rails eninge gem -

what proper syntax nest child modules within parent module being isolate_namespace rails engine gem? # lib/myengine/engine.rb module myengine class engine < rails::engine isolate_namespace myengine # def ... end end for example. parent module myengine , child module blog. myengine share common domain, crud, taggable, searchable, etc, keep gem code dry , isolated main app (myapp), while inheriting isolated namespace , engine. are either of 2 approaches correct? refactor advice? # # lib/myengine/blog.rb module myengine module blog # def ... end end # b # lib/myengine/blog.rb module myengine class engine < rails::engine isolate_namespace myengine module blog # def ... end end end option a. correct, should lib/my_engine/blog.rb . can read more ruby & rails naming conventions here . further, if want put more modules or classes under blog namespace put them in folder lib/my_engine/blog , nest them under myengine::bl...
Read more

php - Why I am getting the Error "Commands out of sync; you can't run this command now" -

the documentation of error mentioned in title says if commands out of sync; can't run command now in client code, calling client functions in wrong order. this can happen, example, if using mysql_use_result() , try execute new query before have called mysql_free_result(). can happen if try execute 2 queries return data without calling mysql_use_result() or mysql_store_result() in between. from here: http://dev.mysql.com/doc/refman/5.0/en/commands-out-of-sync.html but in first query not fetching data mysql database, inserting. , in second query getting data database. here code $connection = mysqli_connect("localhost","username","password","tbl_msgs"); if(mysqli_connect_errno($connection)) { die("failed connect mysql: " . mysqli_connect_error()); } $query = "insert users (total_comments, total_views) values ({$total_comments}, {$total_views});"; $query .= "insert msgs (no...
Read more