» Javascript equivalent for PHP's abs

399 PHP equivalents

PHP to Javascript Project: php.js

php.jsThis article is part of the 'Porting PHP to Javascript' Project, which aims to decrease the gap between developing for PHP & Javascript.

A lot of people are familiar with PHP's functions, and though Javascript functions are often quite similar, some functions may be missing or addressed differently. The Javascript implementations should be as compliant with the PHP versions as possible, a good indication is that the PHP function manual could also apply to the Javascript version.

Porting crucial PHP functions to Javascript can be fun & useful. Currently some PHP functions have been added, but readers are encouraged to contribute and improve functions by adding comments. Eventually the goal is to save all the functions in one php.js file and make it publicly available for your coding pleasure.

If you choose to contribute, let me know how you want to be credited in the function's comments. You may also want to subscribe to RSS so you receive updates whenever new functions are posted.

This is a Javascript version of the PHP function: abs.

I have moved out PHP.JS to it's own site. For info & reactions on comments please goto phpjs.org

PHP abs

Description

abs - Absolute value

number abs ( mixed number)

Returns the absolute value of number.

Parameters

  • number

    The numeric value to process

Return Values

The absoulte value of number . If the argument number is of type float, the return type is also float, otherwise it is integer (as float usually has a bigger value range than integer).

Javascript abs

Source

This is the main source of the Javascript version of PHP's abs

function abs( mixed_number )  {
    // http://kevin.vanzonneveld.net
    // +   original by: Waldo Malqui Silva
    // +   improved by: Karol Kowalski
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: Jonas Raoni Soares Silva (http://www.jsfromhell.com)
    // *     example 1: abs(4.2);
    // *     returns 1: 4.2
    // *     example 2: abs(-4.2);
    // *     returns 2: 4.2
    // *     example 3: abs(-5);
    // *     returns 3: 5
    // *     example 4: abs('_argos');
    // *     returns 4: 0
 
    return Math.abs(mixed_number) || 0;
}

Examples

Currently there are 4 examples

Example 1

This is how you could call abs()
abs(4.2);
And that would return
4.2

Example 2

This is how you could call abs()
abs(-4.2);
And that would return
4.2

Example 3

This is how you could call abs()
abs(-5);
And that would return
5

More about this Project

Download php.js

To easily include it in your code, every function currently available is stored in

Normal

Namespaced What is 'namespaced?'

To download use Right click, Save Link As
Generally the best way is to use a minified version and gzip it


Credits

Respect & awards go to everybody who has contributed in some way so far:

medalmedalBrett Zamir (link) for contributing to:
 array_diff, array_diff_assoc, array_diff_key, array_diff_uassoc, array_diff_ukey, array_fill_keys, array_fill_keys, array_filter, array_intersect, array_intersect_assoc, array_intersect_key, array_intersect_uassoc, array_intersect_ukey, array_keys, array_map, array_merge, array_merge_recursive, array_pop, array_search, array_slice, array_slice, array_splice, array_udiff, array_udiff_assoc, array_udiff_uassoc, array_uintersect, array_uintersect_assoc, array_uintersect_uassoc, array_unique, arsort, arsort, asort, asort, compact, current, each, end, extract, key, krsort, ksort, natcasesort, natcasesort, natsort, natsort, next, pos, prev, reset, rsort, rsort, shuffle, sort, sort, uasort, uasort, uksort, usort, classkit_import, classkit_method_add, classkit_method_copy, classkit_method_redefine, classkit_method_remove, classkit_method_rename, class_exists, get_class_methods, get_class_vars, get_declared_classes, get_object_vars, method_exists, property_exists, ctype_alnum, ctype_alpha, ctype_cntrl, ctype_digit, ctype_graph, ctype_lower, ctype_print, ctype_punct, ctype_space, ctype_upper, ctype_xdigit, date, date, date, date, date_default_timezone_get, date_default_timezone_set, date_parse, gettimeofday, gmdate, gmmktime, gmstrftime, idate, localtime, mktime, strftime, strtotime, timezone_abbreviations_list, timezone_identifiers_list, restore_exception_handler, set_exception_handler, fclose, feof, fgetc, fgetcsv, fgets, fgetss, filemtime, fopen, fpassthru, fread, fseek, ftell, pathinfo, pclose, popen, readfile, rewind, call_user_func, call_user_func_array, create_function, func_get_arg, func_get_args, func_num_args, get_defined_functions, get_defined_functions, register_shutdown_function, assert, assert_options, get_cfg_var, get_defined_constants, get_required_files, getenv, getlastmod, ini_alter, ini_get, ini_get_all, ini_restore, ini_set, php_ini_loaded_file, php_ini_scanned_files, phpversion, putenv, set_time_limit, include, include_once, require, require_once, atan2, expm1, fmod, log1p, rand, constant, define, defined, die, exit, exit, php_strip_whitespace, sleep, time_nanosleep, time_sleep_until, usleep, gopher_parsedir, setrawcookie, aggregate, aggregate_info, aggregate_methods, aggregate_methods_by_list, aggregate_methods_by_regexp, aggregate_properties, aggregate_properties_by_list, aggregate_properties_by_regexp, aggregation_info, deaggregate, preg_grep, sql_regcase, runkit_class_adopt, runkit_class_emancipate, runkit_function_add, runkit_function_copy, runkit_function_redefine, runkit_function_remove, runkit_function_rename, runkit_import, runkit_method_add, runkit_method_copy, runkit_method_redefine, runkit_method_remove, runkit_method_rename, runkit_superglobals, chunk_split, convert_uuencode, count_chars, echo, get_html_translation_table, lcfirst, levenshtein, localeconv, md5, md5_file, nl2br, nl_langinfo, parse_str, printf, quoted_printable_decode, quoted_printable_decode, quoted_printable_encode, setlocale, sha1, soundex, sprintf, str_getcsv, str_ireplace, str_replace, str_replace, str_shuffle, str_split, str_word_count, strcoll, strcspn, strip_tags, strlen, strnatcasecmp, strncmp, strrchr, strspn, strtok, strtr, substr_compare, substr_replace, ucfirst, vprintf, base64_decode, get_headers, get_meta_tags, parse_url, rawurldecode, rawurldecode, rawurlencode, rawurlencode, rawurlencode, urldecode, urldecode, urlencode, urlencode, doubleval, get_defined_vars, get_resource_type, gettype, import_request_variables, import_request_variables, is_array, is_array, is_binary, is_buffer, is_callable, is_real, is_resource, is_unicode, print_r, print_r, settype, strval, strval, unserialize, var_dump, var_export, utf8_decode
spacemedalOnno Marsman for contributing to:
 acos, acosh, asin, asinh, atan, atanh, ceil, cos, cosh, decbin, dechex, decoct, exp, floor, fmod, getrandmax, hypot, is_finite, is_infinite, is_nan, lcg_value, log, log10, max, max, min, min, mt_getrandmax, mt_rand, pi, pow, rand, round, sin, sinh, sqrt, tan, tanh, setcookie, preg_quote, addslashes, bin2hex, count_chars, html_entity_decode, htmlentities, htmlspecialchars_decode, levenshtein, ltrim, nl2br, nl2br, ord, parse_str, rtrim, soundex, str_ireplace, str_replace, str_replace, str_rot13, str_split, strcasecmp, strip_tags, stripos, stripslashes, stristr, strlen, strnatcmp, strncasecmp, strpbrk, strpos, strrev, strripos, strrpos, strstr, strtolower, strtoupper, substr, substr_count, trim, ucfirst, ucwords, base64_decode, empty, empty, is_array, is_bool, isset, utf8_decode, utf8_encode, utf8_encode
spacemedalMichael White (link) for contributing to:
 array_count_values, get_included_files, include, include_once, require, require_once, md5, number_format, parse_str, printf, sha1, sprintf, str_pad, strnatcmp, vprintf, http_build_query, floatval, is_object, print_r
spacemedalWaldo Malqui Silva for contributing to:
 array_fill, array_pad, array_product, array_rand, compact, count, range, abs, defined, ip2long, long2ip, implode, strcmp, strncmp, ucwords, settype
spacemedalPaulo Ricardo F. Santos for contributing to:
 getdate, microtime, constant, define, chop, chunk_split, quotemeta, sprintf, get_headers, gettype, is_double, is_float, is_integer, is_long, is_scalar
spacemedalJack for contributing to:
 compact, max, min, count_chars, htmlentities, md5, parse_str, soundex, sprintf, str_ireplace, strnatcmp, trim, utf8_encode
spacemedalJonas Raoni Soares Silva (link) for contributing to:
 shuffle, abs, setcookie, number_format, number_format, soundex, str_repeat, str_replace, str_rot13, ucwords, wordwrap, wordwrap
spacemedalPhilip Peterson for contributing to:
 sizeof, log10, round, exit, echo, get_html_translation_table, nl2br, str_replace, strchr, urldecode, urlencode, var_export
spacemedalAtes Goral (link) for contributing to:
 array_change_key_case, array_count_values, array_diff_key, each, get_class, preg_quote, addslashes, count_chars, str_rot13, stripslashes
spacemedalLegaev Andrey for contributing to:
 end, reset, file, file_get_contents, function_exists, include, include_once, http_build_query, is_array, is_object
spacemedalMartijn Wieringa for contributing to:
 array_shift, array_unshift, str_ireplace, str_split, strcasecmp, stripos, strnatcmp, substr
spacemedalNate for contributing to:
 array_merge, array_sum, array_unique, pathinfo, addslashes, echo, strncasecmp
spacemedalEnrique Gonzalez for contributing to:
 file_exists, filesize, decbin, decoct, deg2rad, rad2deg
spacemedalPhilippe Baumann for contributing to:
 base_convert, bindec, dechex, hexdec, octdec, empty
spacemedalTheriault for contributing to:
 array_multisort, quoted_printable_decode, quoted_printable_decode, quoted_printable_encode, quoted_printable_encode
spacemedalWebtoolkit.info (link) for contributing to:
 crc32, md5, sha1, utf8_decode, utf8_encode
 
spacemedalAsh Searle (link) for contributing to:
 basename, printf, sprintf, vprintf
spacemedalCarlos R. L. Rodrigues (link) for contributing to:
 array_chunk, array_unique, date, levenshtein
spacemedalJani Hartikainen for contributing to:
 file, file_exists, file_get_contents, filesize
spacemedalOle Vrijenhoek for contributing to:
 convert_uuencode, convert_uuencode, quoted_printable_decode, str_word_count
spacemedaltravc for contributing to:
 rawurldecode, rawurlencode, urldecode, urlencode
spacemedalAlex for contributing to:
 get_html_translation_table, strip_tags, is_int
spacemedalAndrea Giammarchi (link) for contributing to:
 array_map, define, levenshtein
spacemedalErkekjetter for contributing to:
 ltrim, rtrim, trim
spacemedalGeekFG (link) for contributing to:
 krsort, ksort, time
spacemedalJohnny Mast (link) for contributing to:
 array_walk, array_walk_recursive, create_function
spacemedalMichael Grier for contributing to:
 array_unique, wordwrap, rawurlencode
spacemedald3x for contributing to:
 array, explode, unserialize
spacemedalmarrtins for contributing to:
 array_change_key_case, addslashes, stripslashes
spacemedalstag019 for contributing to:
 parse_str, parse_str, http_build_query
spacemedalAJ for contributing to:
 urldecode, urlencode
spacemedalAlfonso Jimenez (link) for contributing to:
 array_reduce, strpbrk
spacemedalAman Gupta for contributing to:
 base64_decode, utf8_decode
spacemedalArpad Ray (mailto:arpad@php.net) for contributing to:
 serialize, unserialize
spacemedalBreaking Par Consulting Inc (link) for contributing to:
 gettimeofday, localtime
spacemedalCaio Ariede (link) for contributing to:
 strtotime, strtotime
spacemedalDavid for contributing to:
 strtotime, is_numeric
spacemedalJosh Fraser (link) for contributing to:
 gettimeofday, localtime
spacemedalKELAN for contributing to:
 get_html_translation_table, gettype
spacemedalKarol Kowalski for contributing to:
 array_reverse, abs
spacemedalLars Fischer for contributing to:
 urldecode, urlencode
spacemedalMarc Palau for contributing to:
 mktime, strip_tags
spacemedalMirek Slugen for contributing to:
 htmlspecialchars, htmlspecialchars_decode
spacemedalOleg Eremeev for contributing to:
 str_replace, str_replace
spacemedalPellentesque Malesuada for contributing to:
 base64_decode, base64_encode
spacemedalPublic Domain (link) for contributing to:
 json_decode, json_encode
spacemedalSakimori for contributing to:
 strlen, wordwrap
spacemedalSteve Hilder for contributing to:
 strcmp, strncmp
spacemedalSteven Levithan (link) for contributing to:
 trim, parse_url
spacemedalThunder.m for contributing to:
 base64_decode, base64_encode
spacemedalTyler Akins (link) for contributing to:
 base64_decode, base64_encode
spacemedalgettimeofday for contributing to:
 date, idate
spacemedalgorthaur for contributing to:
 strcmp, strncmp
spacemedalmdsjack (link) for contributing to:
 include, trim
spacemedal0m3r for contributing to:
 array_diff_assoc
spacemedalAlexander Ermolaev (link) for contributing to:
 trim
spacemedalAllan Jensen (link) for contributing to:
 number_format
spacemedalAndreas for contributing to:
 setcookie
spacemedalAndrej Pavlovic for contributing to:
 serialize
spacemedalAnton Ongson for contributing to:
 str_replace
spacemedalArno for contributing to:
 htmlspecialchars
spacemedalAtli Þór for contributing to:
 nl2br
spacemedalBayron Guevara for contributing to:
 base64_encode
spacemedalBen Bryan for contributing to:
 print_r
spacemedalBenjamin Lupton for contributing to:
 number_format
spacemedalBlues (link) for contributing to:
 strftime
spacemedalBlues at link for contributing to:
 setlocale
spacemedalBobby Drake for contributing to:
 strip_tags
spacemedalBrad Touesnard for contributing to:
 date
spacemedalBryan Elliott for contributing to:
 date
spacemedalCagri Ekin for contributing to:
 parse_str
spacemedalChaosNo1 for contributing to:
 timezone_abbreviations_list
spacemedalChristian Doebler for contributing to:
 sleep
spacemedalCord for contributing to:
 is_array
spacemedalDaniel Esteban for contributing to:
 strpos
spacemedalDavid James for contributing to:
 get_class
spacemedalDavid Randall for contributing to:
 date
spacemedalDer Simon (link) for contributing to:
 echo
spacemedalDino for contributing to:
 serialize
spacemedalDiogo Resende for contributing to:
 number_format
spacemedalDouglas Crockford (link) for contributing to:
 gettype
spacemedalDxGx for contributing to:
 trim
spacemedalEric Nagel for contributing to:
 strip_tags
spacemedalEugene Bulkin (link) for contributing to:
 echo
spacemedalFGFEmperor for contributing to:
 mktime
spacemedalFelix Geisendoerfer (link) for contributing to:
 array_key_exists
spacemedalFrancesco for contributing to:
 empty
spacemedalFrancois for contributing to:
 htmlspecialchars_decode
spacemedalFremyCompany for contributing to:
 isset
spacemedalGabriel Paderni for contributing to:
 str_replace
spacemedalGaragoth for contributing to:
 serialize
spacemedalGilbert for contributing to:
 array_sum
spacemedalHoward Yeend for contributing to:
 number_format
spacemedalHyam Singer (link) for contributing to:
 exit
spacemedalJ A R for contributing to:
 end
spacemedalJalal Berrami for contributing to:
 import_request_variables
spacemedalKirk Strobeck for contributing to:
 strlen
spacemedalKristof Coomans (SCK-CEN (Belgian Nucleair Research Centre)) for contributing to:
 strnatcasecmp
spacemedalLH for contributing to:
 empty
spacemedalLeslie Hoare for contributing to:
 rand
spacemedalLincoln Ramsay for contributing to:
 basename
spacemedalLinuxworld for contributing to:
 bin2hex
spacemedalLuke Godfrey for contributing to:
 strip_tags
spacemedalLuke Smith (link) for contributing to:
 number_format
spacemedalManish for contributing to:
 is_array
spacemedalMarc Jansen for contributing to:
 empty
spacemedalMarco for contributing to:
 get_html_translation_table
spacemedalMartin Pool for contributing to:
 strnatcasecmp
spacemedalMateusz "loonquawl" Zalega for contributing to:
 htmlspecialchars_decode
spacemedalMatt Bradley for contributing to:
 is_int
spacemedalMeEtc (link) for contributing to:
 date
spacemedalMick@el for contributing to:
 stripslashes
spacemedalNathan for contributing to:
 htmlspecialchars
spacemedalNick Callen for contributing to:
 wordwrap
spacemedalNorman "zEh" Fuchs for contributing to:
 utf8_decode
spacemedalOle Vrijenhoek (link) for contributing to:
 filemtime
spacemedalOzh for contributing to:
 dirname
spacemedalPaul for contributing to:
 exit
spacemedalPedro Tainha (link) for contributing to:
 unserialize
spacemedalPeter-Paul Koch (link) for contributing to:
 date
spacemedalPierre-Luc Paour for contributing to:
 strnatcasecmp
spacemedalPul for contributing to:
 strip_tags
spacemedalPyerre for contributing to:
 checkdate
spacemedalReverseSyntax for contributing to:
 htmlspecialchars_decode
spacemedalRival for contributing to:
 number_format
spacemedalRobin for contributing to:
 is_nan
spacemedalSanjoy Roy for contributing to:
 array_diff
spacemedalSaulo Vallory for contributing to:
 strncasecmp
spacemedalScott Cariss for contributing to:
 htmlspecialchars_decode
spacemedalSimon Willison (link) for contributing to:
 str_replace
spacemedalSlawomir Kaniecki for contributing to:
 htmlspecialchars_decode
spacemedalSoren Hansen for contributing to:
 count
spacemedalSteve Clay for contributing to:
 function_exists
spacemedalSubhasis Deb for contributing to:
 array_merge_recursive
spacemedalT. Wild for contributing to:
 filesize
spacemedalT.Wild for contributing to:
 substr
spacemedalT0bsn for contributing to:
 crc32
spacemedalThiago Mata (link) for contributing to:
 call_user_func_array
spacemedalTim Wiel for contributing to:
 date
spacemedalTim de Koning for contributing to:
 is_numeric
spacemedalTod Gentille for contributing to:
 log10
spacemedalValentina De Rosa for contributing to:
 strspn
spacemedalVictor for contributing to:
 ip2long
spacemedalWagner B. Soares for contributing to:
 strtotime
spacemedalXoraX (link) for contributing to:
 dirname
spacemedalYUI Library: link for contributing to:
 setlocale
spacemedalYannoo for contributing to:
 mktime
spacemedalYves Sucaet for contributing to:
 utf8_encode
spacemedalbaris ozdil for contributing to:
 mktime
spacemedalbooeyOH for contributing to:
 preg_quote
spacemedalclass_exists for contributing to:
 get_declared_classes
spacemedaldate for contributing to:
 idate
spacemedaldjmix for contributing to:
 basename
spacemedaldptr1988 for contributing to:
 unserialize
spacemedalduncan for contributing to:
 array_unique
spacemedalecho is bad for contributing to:
 echo
spacemedalejsanders for contributing to:
 vsprintf
spacemedalgabriel paderni for contributing to:
 mktime
spacemedalger for contributing to:
 html_entity_decode
spacemedalhitwork for contributing to:
 utf8_decode
spacemedaljakes for contributing to:
 mktime
spacemedaljohn (link) for contributing to:
 html_entity_decode
spacemedaljohnrembo for contributing to:
 var_export
spacemedalkenneth for contributing to:
 explode
spacemedalmadipta for contributing to:
 get_html_translation_table
spacemedalmarc andreu for contributing to:
 html_entity_decode
spacemedalmetjay for contributing to:
 time
spacemedalmk.keck for contributing to:
 realpath
spacemedalmktime for contributing to:
 gmmktime
spacemedalnobbler for contributing to:
 htmlentities
spacemedalnoname for contributing to:
 get_html_translation_table
spacemedalpenutbutterjelly for contributing to:
 str_ireplace
spacemedalrezna for contributing to:
 stripslashes
spacemedalsankai for contributing to:
 array_count_values
spacemedalsetcookie for contributing to:
 setrawcookie
spacemedalsowberry for contributing to:
 utf8_encode
spacemedalstensi for contributing to:
 intval
spacemedalstrcasecmp, strcmp for contributing to:
 substr_compare
spacemedaltaith for contributing to:
 is_numeric
spacemedaluestla for contributing to:
 strtr

Your name here?

Contributing is as easy as adding a comment with better code, or code for a new function.
Any contribution leading to improvement will directly get your name & link here.


Coming Project features

Project features that we are currently working on:

  • Done - Site. A place for php.js of it's own. See: phpjs.org.
  • Done - Compile. Compile your own php.js version, with only the functions you need. Should generate a hash with which you can retrieve latest versions of your php.js combination.
  • Done - Testsuite. A better test-suite that can be ran locally so developers can easily test before commiting. Also the testing itself should be more thorough.
  • Done - Versioning. Individual functions are versioned, but the entire library should be versioned as well.

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tags: programming, php, javascript
category: Programming - Javascript - PHP equivalents
read: 20,017 times

Add Comment

PHP.JS is outgroing this blog and moving to it's own space. Please leave your comment here: http://phpjs.org/functions/abs

Comments

#19. Kevin on 16 March 2009

Member avatar: Kevin@ Jay: I will review your comment soon over at http://phpjs.org . Please bear with me, and use that new site for comments on PHP.JS from now on.

Thanks a lot!!

#18. Jay on 06 March 2009

Gravatar.com: JayYou should really consider putting this project up on GitHub.com, it would be a perfect fit. That way people could modify and improve the code, and then send you a pull request for you to merge their changes. It's a very nice way to develop open source projects.

#17. Kevin on 15 January 2009

Member avatar: Kevin@ Paul: It was actually an issue in the exit function. Should be fixed now, thanks for letting us know!

#16. Paul on 15 January 2009

Gravatar.com: PaulI downloaded php.namespaced.*.js at 2009-01-14 15:28 HST. There appears to be a space missing which is causing javascript errors. Search string "functionPropagation". I was able to resolve the error in php.namespaced.js and php.namespaced.min.js, but not php.namespaced.packed.js due to the packing operation.

BTW: This package is incredible!

#15. Kevin on 12 January 2009

Member avatar: Kevin@ Nile: Hey Nile thanks for your contribution. Unfortunately there are a couple of issues with it:
- depends on an outside function: applyEncode
- does not support associative arrays (in terms of traversing)
- does not support index arrays, numbers, etc (in terms of encoding)

... [more] Please have a look here:
http://www.json.org/json2.js

The code is public domain, so maybe it's possible to modify it and use it in PHP.JS. We could look into that!

#14. Nile on 09 January 2009

Gravatar.com: Nilejson_encode

var arr = new Array('Hello');
var applyEncode = function(varIn){
return '{'+varIn+'}';
}
var json_encode = function(value){
var data = '';
for(i=0,endCount='';i<value.length;++i){
var endCount = (i!=value.length-1) ? ", " : "";
data += '"'+key(value[i])+'" : "'+value[key(value)]+'"'+endCount;
}
return applyEncode(data);
}
document.write(json_encode(arr));

#13. Reena on 08 September 2008

Gravatar.com: ReenaGood

#12. Kevin on 13 April 2008

Member avatar: Kevin@ Jonas Raoni: Thanks I'll update the function.
@ Philip: I'll update your name!

#11. Philip on 12 April 2008

Default avatar:PhilipHey, just fyi... Philip and Philip Peterson are both me ;-)

#10. Jonas Raoni on 12 April 2008

Default avatar:Jonas RaoniA shorter version of this would be:

return Math.abs (n) || 0;

#9. Kevin on 02 April 2008

Member avatar: KevinPhilip: Good idea, I'll add it, thanks!

#8. Philip on 31 March 2008

Default avatar:PhilipDunno where this belongs, but how about this code for echo()?

function echo()
{
for(i=0;i<echo.arguments.length;i++)
{
if(document.body && document.body.innerHTML) {
document.body.innerHTML=document.body.innerHTML+echo.arguments[i];
} else {
document.write(echo.arguments[i]);
}
}
}

#7. Kevin on 31 January 2008

Member avatar: Kevin@ _argos: Nice work! Added!

#6. _argos on 31 January 2008

Default avatar:_argosHi Kevin I'm here again look this ports.

if ( defined ( 'CONSTANTE' ) ) {
 
console.log ( CONSTANTE );
 
}
 
function defined ( constant_name ) {
 
return ( ( window [ constant_name ] !== undefined ) ? true : false );
 
}
 
 
 
// -----
 
// [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
 
console.log ( range ( 0, 12 ) );
 
 
 
// [0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100]
 
console.log ( range( 0, 100, 10 ) );
 
 
 
// ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i'];
 
console.log ( range( 'a', 'i' ) );
 
 
 
// ['c', 'b', 'a'];
 
console.log ( range ('c', 'a' ) );
 
 
 
function range ( low, high, step ) {
 
var matrix = [];
 
var inival, endval, plus;
 
var walker = step || 1;
 
var chars = false;
 

 
if ( !isNaN ( low ) && !isNaN ( high ) ) {
 
inival = low;
 
endval = high;
 
} else if ( isNaN ( low ) && isNaN ( high ) ) {
 
chars = true;
 
inival = low.charCodeAt ( 0 );
 
endval = high.charCodeAt ( 0 );
 
} else {
 
inival = ( isNaN ( low ) ? 0 : low );
 
endval = ( isNaN ( high ) ? 0 : high );
 
}
 

 
plus = ( ( inival > endval ) ? false : true );
 

 
if ( plus ) {
 
while ( inival <= endval ) {
 
matrix.push ( ( ( chars ) ? String.fromCharCode ( inival ) : inival ) );
 
inival += walker;
 
}
 
} else {
 
while ( inival >= endval ) {
 
matrix.push ( ( ( chars ) ? String.fromCharCode ( inival ) : inival ) );
 
inival -= walker;
 
}
 
}
 

 
return matrix;
 
}
 
 
 
// -----
 
console.log ( strcmp ( 'waldo', 'Waldo' ) );
 
console.log ( strcmp ( 'Waldo', 'waldo' ) );
 
console.log ( strcmp ( 'waldo', 'waldo' ) );
 
 
 
function strcmp ( str1, str2 ) {
 
var size1 = str1.charCodeAt ( 0 );
 
var size2 = str2.charCodeAt ( 0 );
 

 
return ( ( size1 == size2 ) ? 0 : ( ( size1 > size2 ) ? 1 : -1 ) );
 
}

#5. _argos on 30 January 2008

Default avatar:_argos@Karol Kowalski : Hi, thanks for take the time to check my port, I make the same tests like you, because I think that native functions always are more slower, so ever I use self hacks :p again thanxs for your time.

PS: Sorry for my badly English, but i have 4 years without use it :p

#4. Kevin on 30 January 2008

Member avatar: Kevin@ Karol Kowalski: Awesome work Karol! I've updated the function. Thanks for putting in the extra effort. Greatly appreciated!

#3. Karol Kowalski on 30 January 2008

Default avatar:Karol KowalskiI run a test and it appeared that my function with Math.abs was around 40% more time consuming than yours. I tried to optimize it and ended up with 20% gain, and the code is still smaller and more readable. I tested it in Firefox, IE7, Safari and Opera with similar results. To see what's causing the overhead I run a function that would just return Math.abs, withoud checking for validity, still it was 10% slower than your function. It seems that Math.abs API is always slower than what can be accomplished with JS hack, a bit sad.

Still, for code readability I would sugget using the code of abs_math2.

Here's the test code:

if (!window['console']) {
 
console={}
console.log=alert
}
 
var start;
 
function abs_math2 ( mixed_number ) {
return ( ( isNaN ( mixed_number ) ) ? 0 : Math.abs ( mixed_number ) );
}
 
function abs_math( mixed_number ) {
var abs=Math.abs( mixed_number );
return ( !isNaN ( abs ) ) ? abs : 0
}
 
function abs_cond( mixed_number ) {
return ( ( !isNaN ( mixed_number ) ) ? ( ( mixed_number < 0 ) ? ( mixed_number * -1 ) : mixed_number ) : 0 );
}
 
 
start=new Date();
 
for (var i=100000;i;i--) {
 
abs_cond(4.2);
abs_cond(-4.2);
abs_cond(-5);
abs_cond('_argos');
abs_cond(-Infinity);
 
}
 
console.log((new Date())-start)
 
 
start=new Date();
 
for (var i=100000;i;i--) {
 
abs_math(4.2);
abs_math(-4.2);
abs_math(-5);
abs_math('_argos');
abs_math(-Infinity);
 
}
 
console.log((new Date())-start)
 
 
start=new Date();
 
for (var i=100000;i;i--) {
 
abs_math2(4.2);
abs_math2(-4.2);
abs_math2(-5);
abs_math2('_argos');
abs_math2(-Infinity);
 
}
 
console.log((new Date())-start)
 
 
//my results
//Firefox 2.0.11
//1000
//1422
//1219

#2. Kevin on 30 January 2008

Member avatar: Kevin@ Karol Kowalski: Using native Javascript for this is probably best so I've updated the function. But I'm not totally certain that this is faster. Doesn't the Math libary have to be loaded or something? Can somebod shed a light on this?

For reference, this was the original by _argos:

function abs( mixed_number )  {
// + original by: _argos
return ( ( !isNaN ( mixed_number ) ) ? ( ( mixed_number < 0 ) ? ( mixed_number * -1 ) : mixed_number ) : 0 );
}

#1. Karol Kowalski on 30 January 2008

Default avatar:Karol KowalskiWhy not use native JS Math.abs for this. I believe this should be faster than conditional expressions.

function abs( mixed_number )  {
// http://kevin.vanzonneveld.net
// + original by: _argos
// * example 1: abs(4.2);
// * returns 1: 4.2
// * example 2: abs(-4.2);
// * returns 2: 4.2
// * example 3: abs(-5);
// * returns 3: 5
// * example 4: abs('_argos');
// * returns 4: 0
 
var abs=Math.abs( mixed_number )
return ( !isNaN ( abs) ) ? abs : 0
}