php : result of sum array values is wrong -

-

i have array:

$test =array('49'=> '-0','51'=> '-0','50'=> '0','53'=> '-1.69','55'=> '0','57'=> '-2','59'=> '-6','60'=> '-12','65'=> '0','66'=> '0','67'=> '21.69','69'=> '0','70'=> '0','71'=> '0',);   echo "\n".'===== first method ========'; echo "\n\n".print_r($test); echo "\n array_sum: ".array_sum($test); echo "\n\n".'===== second method ========';  $total = 0;foreach($test $value) $total += $value; echo "\n foreach:".$total."\n";

the result 

gd@gd:~/desktop$ php test.php  ===== first method ========array (     [49] => -0     [51] => -0     [50] => 0     [53] => -1.69     [55] => 0     [57] => -2     [59] => -6     [60] => -12     [65] => 0     [66] => 0     [67] => 21.69     [69] => 0     [70] => 0     [71] => 0 )   1  array_sum: 3.5527136788005e-15  ===== second method ========  foreach:3.5527136788005e-15

it wrong, result should 0, not 3.5527136788e-15, how fix ?

this standard floating point arithmetic precision error.

php -r "echo -1.69 + -2 + -6 + -12 +21.69;" 3.5527136788005e-15%

you can fix using ints rather floats. example, if expect 2 digits of precision, multiply numbers 100, round them off ints, sum them, , divide 100.

php -r "echo (-169 + -200 -1200 +2169 + -600) / 100;" 0%

Comments

Post a Comment

Popular posts from this blog

java - Run a .jar on Heroku -

-
i trying run .jar file on heroku, , can't find instructions anywhere on how this. have read wants me compile uploading heroku. possible, , if is, how this? if helps, trying run minecraft craftbukkit server, , don't have pom.xml file yet. you didn't provide details i'll try give , people reaches question way it. first of all, create heroku account , create heroku application (assumed have done that). second, need generate application jar , upload heroku. so, open terminal , install heroku cli (assuming unix terminal): $ sudo npm install -g heroku-cli you need have npm , nodejs installed, can check link: https://www.digitalocean.com/community/tutorials/how-to-install-node-js-on-ubuntu-16-04 once done that, can use npm update node version acceptable heroku-cli: $ sudo npm install -g n $ sudo n 7.10.0 and run: $ sudo npm install -g heroku-cli in order deploy jars, need install deploy plugin: $ sudo heroku plugins:install heroku-cli-deploy ...
Read more

java - Jtable duplicate Rows -

-
Image
when add new rows in jtable duplicate rows many times this method update jtable public final void tableaucomande(){ ((defaulttablemodel)tabcommande.getmodel()).getdatavector().clear(); session s=hibernateutil.getsessionfactory().opensession(); criteria cr1= s.createcriteria(commande.class); list <commande> lcs=cr1.list() ; criteria cr2= s.createcriteria(lignecommande.class); list <lignecommande> lck=cr2.list() ; if(lcs.size()!=0 && lck.size()!=0) { (commande lc:lcs) { for(lignecommande lig:lck){ ((defaulttablemodel)tabcommande.getmodel()).addrow(new object[]{ lc.getid_cmd(),lc.getnumcmd(),lc.getdate_cmd(),lc.getclient().getnomprenom(), lig.getproduit().getlib_prd(),lig.getquantite(),lig.getproduit().getid_prd() }); } } // tabcommande.setrowselectioninterval(tabcommande.getrowcount()-1,tabcommande.getrowcount()-1); } } this code add add data rows displaye...
Read more

validation - How to pass paramaters like unix into windows batch file -

-
i need pass various parameters .cmd file unix format file.cmd -configuration=value -source=value -flag but, try this: startlocal @echo off cls setlocal set cmdline=%* set configuration= set source= set badargs= set validation= goto main :splitargs echo splitargs(%*) if "%*" neq "" ( /f "tokens=1,2,* delims== " %%i in ("%*") call :assignkeyvalue %%i %%j & call :splitargs %%k ) goto :eof :assignkeyvalue echo assignkeyvalue(%1, %2) if /i %1==-configuration ( set configuration=%2 ) else if /i %1==-source ( set source=%2 ) else ( rem append unrecognised [key,value] badargs echo unknown key %1 set badargs=%badargs%[%1, %2] ) goto :eof :validate echo validating set validation=fail if defined configuration ( echo -configuration ok if defined source ( echo -source ok if not defined badargs ( set validation=success ) ) ) goto :eof :main cl...
Read more