Splitting up jQuery to make it easier to understand

I have some jQuery code that I downloaded from a site and I want to make it easier to understand.

Can anyone help me get it to a state where I can remove parts of unused code?

(function(a){var A=function(s,v){var f=a.extend({},a.fn.nivoSlider.defaults,v),g={currentSlide:0,currentImage:"",totalSlides:0,randAnim:"",running:false,paused:false,stop:false},e=a(s);e.data("nivo:vars",g);e.css("position","relative");e.addClass("nivoSlider");var j=e.children();j.each(function(){var b=a(this),h="";if(!b.is("img")){if(b.is("a")){b.addClass("nivo-imageLink");h=b}b=b.find("img:first")}var c=b.width();if(c==0)c=b.attr("width");var o=b.height();if(o==0)o=b.attr("height");c>e.width()&&
e.width(c);o>e.height()&&e.height(o);h!=""&&h.css("display","none");b.css("display","none");g.totalSlides++});if(f.startSlide>0){if(f.startSlide>=g.totalSlides)f.startSlide=g.totalSlides-1;g.currentSlide=f.startSlide}g.currentImage=a(j[g.currentSlide]).is("img")?a(j[g.currentSlide]):a(j[g.currentSlide]).find("img:first");a(j[g.currentSlide]).is("a")&&a(j[g.currentSlide]).css("display","block");e.css("background",'url("'+g.currentImage.attr("src")+'") no-repeat');for(var k=0;k<f.slices;k++){var p=
Math.round(e.width()/f.slices);k==f.slices-1?e.append(a('<div class="nivo-slice"></div>').css({left:p*k+"px",width:e.width()-p*k+"px"})):e.append(a('<div class="nivo-slice"></div>').css({left:p*k+"px",width:p+"px"}))}e.append(a('<div class="nivo-caption"><p></p></div>').css({display:"none",opacity:f.captionOpacity}));if(g.currentImage.attr("title")!=""){k=g.currentImage.attr("title");if(k.substr(0,1)=="#")k=a(k).html();a(".nivo-caption p",e).html(k);a(".nivo-caption",e).fadeIn(f.animSpeed)}var l=
0;if(!f.manualAdvance&&j.length>1)l=setInterval(function(){r(e,j,f,false)},f.pauseTime);if(f.directionNav){e.append('<div class="nivo-directionNav"><a class="nivo-prevNav">Prev</a><a class="nivo-nextNav">Next</a></div>');if(f.directionNavHide){a(".nivo-directionNav",e).hide();e.hover(function(){a(".nivo-directionNav",e).show()},function(){a(".nivo-directionNav",e).hide()})}a("a.nivo-prevNav",e).live("click",function(){if(g.running)return false;clearInterval(l);l="";g.currentSlide-=2;r(e,j,f,"prev")});
a("a.nivo-nextNav",e).live("click",function(){if(g.running)return false;clearInterval(l);l="";r(e,j,f,"next")})}if(f.controlNav){p=a('<div class="nivo-controlNav"></div>');e.append(p);for(k=0;k<j.length;k++)if(f.controlNavThumbs){var t=j.eq(k);t.is("img")||(t=t.find("img:first"));f.controlNavThumbsFromRel?p.append('<a class="nivo-control" rel="'+k+'"><img src="'+t.attr("rel")+'" alt="" /></a>'):p.append('<a class="nivo-control" rel="'+k+'"><img src="'+t.attr("src").replace(f.controlNavThumbsSearch,
f.controlNavThumbsReplace)+'" alt="" /></a>')}else p.append('<a class="nivo-control" rel="'+k+'">'+(k+1)+"</a>");a(".nivo-controlNav a:eq("+g.currentSlide+")",e).addClass("active");a(".nivo-controlNav a",e).live("click",function(){if(g.running)return false;if(a(this).hasClass("active"))return false;clearInterval(l);l="";e.css("background",'url("'+g.currentImage.attr("src")+'") no-repeat');g.currentSlide=a(this).attr("rel")-1;r(e,j,f,"control")})}f.keyboardNav&&a(window).keypress(function(b){if(b.keyCode==
"37"){if(g.running)return false;clearInterval(l);l="";g.currentSlide-=2;r(e,j,f,"prev")}if(b.keyCode=="39"){if(g.running)return false;clearInterval(l);l="";r(e,j,f,"next")}});f.pauseOnHover&&e.hover(function(){g.paused=true;clearInterval(l);l=""},function(){g.paused=false;if(l==""&&!f.manualAdvance)l=setInterval(function(){r(e,j,f,false)},f.pauseTime)});e.bind("nivo:animFinished",function(){g.running=false;a(j).each(function(){a(this).is("a")&&a(this).css("display","none")});a(j[g.currentSlide]).is("a")&&
a(j[g.currentSlide]).css("display","block");if(l==""&&!g.paused&&!f.manualAdvance)l=setInterval(function(){r(e,j,f,false)},f.pauseTime);f.afterChange.call(this)});var w=function(b,h){var c=0;a(".nivo-slice",b).each(function(){var o=a(this),d=Math.round(b.width()/h.slices);c==h.slices-1?o.css("width",b.width()-d*c+"px"):o.css("width",d+"px");c++})},r=function(b,h,c,o){var d=b.data("nivo:vars");d&&d.currentSlide==d.totalSlides-1&&c.lastSlide.call(this);if((!d||d.stop)&&!o)return false;c.beforeChange.call(this);
if(o){o=="prev"&&b.css("background",'url("'+d.currentImage.attr("src")+'") no-repeat');o=="next"&&b.css("background",'url("'+d.currentImage.attr("src")+'") no-repeat')}else b.css("background",'url("'+d.currentImage.attr("src")+'") no-repeat');d.currentSlide++;if(d.currentSlide==d.totalSlides){d.currentSlide=0;c.slideshowEnd.call(this)}if(d.currentSlide<0)d.currentSlide=d.totalSlides-1;d.currentImage=a(h[d.currentSlide]).is("img")?a(h[d.currentSlide]):a(h[d.currentSlide]).find("img:first");if(c.controlNav){a(".nivo-controlNav a",
b).removeClass("active");a(".nivo-controlNav a:eq("+d.currentSlide+")",b).addClass("active")}if(d.currentImage.attr("title")!=""){var u=d.currentImage.attr("title");if(u.substr(0,1)=="#")u=a(u).html();a(".nivo-caption",b).css("display")=="block"?a(".nivo-caption p",b).fadeOut(c.animSpeed,function(){a(this).html(u);a(this).fadeIn(c.animSpeed)}):a(".nivo-caption p",b).html(u);a(".nivo-caption",b).fadeIn(c.animSpeed)}else a(".nivo-caption",b).fadeOut(c.animSpeed);var m=0;a(".nivo-slice",b).each(function(){var i=
Math.round(b.width()/c.slices);a(this).css({height:"0px",opacity:"0",background:'url("'+d.currentImage.attr("src")+'") no-repeat -'+(i+m*i-i)+"px 0%"});m++});if(c.effect=="random"){h=["sliceDownRight","sliceDownLeft","sliceUpRight","sliceUpLeft","sliceUpDown","sliceUpDownLeft","fold","fade","slideInRight","slideInLeft"];d.randAnim=h[Math.floor(Math.random()*(h.length+1))];if(d.randAnim==undefined)d.randAnim="fade"}if(c.effect.indexOf(",")!=-1){h=c.effect.split(",");d.randAnim=h[Math.floor(Math.random()*
h.length)];if(d.randAnim==undefined)d.randAnim="fade"}d.running=true;if(c.effect=="sliceDown"||c.effect=="sliceDownRight"||d.randAnim=="sliceDownRight"||c.effect=="sliceDownLeft"||d.randAnim=="sliceDownLeft"){var n=0;m=0;w(b,c);h=a(".nivo-slice",b);if(c.effect=="sliceDownLeft"||d.randAnim=="sliceDownLeft")h=a(".nivo-slice",b)._reverse();h.each(function(){var i=a(this);i.css({top:"0px"});m==c.slices-1?setTimeout(function(){i.animate({height:"100%",opacity:"1.0"},c.animSpeed,"",function(){b.trigger("nivo:animFinished")})},
100+n):setTimeout(function(){i.animate({height:"100%",opacity:"1.0"},c.animSpeed)},100+n);n+=50;m++})}else if(c.effect=="sliceUp"||c.effect=="sliceUpRight"||d.randAnim=="sliceUpRight"||c.effect=="sliceUpLeft"||d.randAnim=="sliceUpLeft"){m=n=0;w(b,c);h=a(".nivo-slice",b);if(c.effect=="sliceUpLeft"||d.randAnim=="sliceUpLeft")h=a(".nivo-slice",b)._reverse();h.each(function(){var i=a(this);i.css({bottom:"0px"});m==c.slices-1?setTimeout(function(){i.animate({height:"100%",opacity:"1.0"},c.animSpeed,"",
function(){b.trigger("nivo:animFinished")})},100+n):setTimeout(function(){i.animate({height:"100%",opacity:"1.0"},c.animSpeed)},100+n);n+=50;m++})}else if(c.effect=="sliceUpDown"||c.effect=="sliceUpDownRight"||d.randAnim=="sliceUpDown"||c.effect=="sliceUpDownLeft"||d.randAnim=="sliceUpDownLeft"){var x=m=n=0;w(b,c);h=a(".nivo-slice",b);if(c.effect=="sliceUpDownLeft"||d.randAnim=="sliceUpDownLeft")h=a(".nivo-slice",b)._reverse();h.each(function(){var i=a(this);if(m==0){i.css("top","0px");m++}else{i.css("bottom",
"0px");m=0}x==c.slices-1?setTimeout(function(){i.animate({height:"100%",opacity:"1.0"},c.animSpeed,"",function(){b.trigger("nivo:animFinished")})},100+n):setTimeout(function(){i.animate({height:"100%",opacity:"1.0"},c.animSpeed)},100+n);n+=50;x++})}else if(c.effect=="fold"||d.randAnim=="fold"){m=n=0;w(b,c);a(".nivo-slice",b).each(function(){var i=a(this),y=i.width();i.css({top:"0px",height:"100%",width:"0px"});m==c.slices-1?setTimeout(function(){i.animate({width:y,opacity:"1.0"},c.animSpeed,"",function(){b.trigger("nivo:animFinished")})},
100+n):setTimeout(function(){i.animate({width:y,opacity:"1.0"},c.animSpeed)},100+n);n+=50;m++})}else if(c.effect=="fade"||d.randAnim=="fade"){var q=a(".nivo-slice:first",b);q.css({height:"100%",width:b.width()+"px"});q.animate({opacity:"1.0"},c.animSpeed*2,"",function(){b.trigger("nivo:animFinished")})}else if(c.effect=="slideInRight"||d.randAnim=="slideInRight"){q=a(".nivo-slice:first",b);q.css({height:"100%",width:"0px",opacity:"1"});q.animate({width:b.width()+"px"},c.animSpeed*2,"",function(){b.trigger("nivo:animFinished")})}else if(c.effect==
"slideInLeft"||d.randAnim=="slideInLeft"){q=a(".nivo-slice:first",b);q.css({height:"100%",width:"0px",opacity:"1",left:"",right:"0px"});q.animate({width:b.width()+"px"},c.animSpeed*2,"",function(){q.css({left:"0px",right:""});b.trigger("nivo:animFinished")})}},z=function(b){this.console&&typeof console.log!="undefined"&&console.log(b)};this.stop=function(){if(!a(s).data("nivo:vars").stop){a(s).data("nivo:vars").stop=true;z("Stop Slider")}};this.start=function(){if(a(s).data("nivo:vars").stop){a(s).data("nivo:vars").stop=
false;z("Start Slider")}};f.afterLoad.call(this)};a.fn.nivoSlider=function(s){return this.each(function(){var v=a(this);if(!v.data("nivoslider")){var f=new A(this,s);v.data("nivoslider",f)}})};a.fn.nivoSlider.defaults={effect:"random",slices:15,animSpeed:500,pauseTime:3E3,startSlide:0,directionNav:true,directionNavHide:true,controlNav:true,controlNavThumbs:false,controlNavThumbsFromRel:false,controlNavThumbsSearch:".jpg",controlNavThumbsReplace:"_thumb.jpg",keyboardNav:true,pauseOnHover:true,manualAdvance:false,
captionOpacity:0.8,beforeChange:function(){},afterChange:function(){},slideshowEnd:function(){},lastSlide:functi开发者_C百科on(){},afterLoad:function(){}};a.fn._reverse=[].reverse})(jQuery);

The first thing you could do with this is to run it through a beautifier.

(function (a) {
    var A = function (s, v) {
        var f = a.extend({}, a.fn.nivoSlider.defaults, v),
            g = {
                currentSlide: 0,
                currentImage: "",
                totalSlides: 0,
                randAnim: "",
                running: false,
                paused: false,
                stop: false
            },
            e = a(s);
        e.data("nivo:vars", g);
// etc...

It seems that it's the source code for nivoSlider. If you compare the above beautified code with the nivoSlider source code others have posted you can see the similarity.

That is minified code. It's very hard to reread due to the renaming of variables. If you just want to read the code itself, paste it into http://www.jsbeautifier.com/

Download your uncompressed code here: http://nivo.dev7studios.com/

Use JS Beautifier to make the code readable http://jsbeautifier.org/

..then you can easily edit the code and remove unused code as you wish.

Other useful tools

For the actual jQuery library (the code you included does not appear to be the actual library), download the un-minified version.. it will make a lot more sense

http://code.jquery.com/jquery-1.5.js

As for the code your're showing, you can use a beautifier as other answers have pointed out.