Call easySlider animate function in another JS function

I am struggling to make custome next and prev links for easySlider. I found animate function in slider JS file. But i try to call it from my own JS function. I get function not defined error. Here is JS code for slider.

(function($) {

    $.fn.easySlider = function(options){

        // default configuration properties
        var defaults = {            
            prevId:         'prevBtn',
            prevText:       'Previous',
            nextId:         'nextBtn',  
            nextText:       'Next',
            controlsShow:   true,
            controlsBefore: '',
            controlsAfter:  '', 
            controlsFade:   true,
            firstId:        'firstBtn',
            firstText:      'First',
            firstShow:      false,
            lastId:         'lastBtn',  
            lastText:       'Last',
            lastShow:       false,              
            vertical:       false,
            speed:          800,
            auto:           false,
            pause:          2000,
            continuous:     false
        }; 

        var options = $.extend(defaults, options);  

        this.each(function() {  
            var obj = $(this);              
            var s = $("li", obj).length;
            var w = $("li", obj).width(); 
            var h = $("li", obj).height(); 
            obj.width(w); 
            obj.height(h); 
            obj.css("overflow","hidden");
            var ts = s-1;
            var t = 0;
            $("ul", obj).css('width',s*w);          
            if(!options.vertical) $("li", obj).css('float','left');

            if(options.controlsShow){
                var html = options.controlsBefore;
                if(options.firstShow) html += '<span id="'+ options.firstId +'"><a href=\"javascript:void(0);\">'+ options.firstText +'</a></span>';
                html += ' <span id="'+ options.prevId +'"><a href=\"javascript:void(0);\">'+ options.prevText +'</a></span>';
                html += ' <span id="'+ options.nextId +'"><a href=\"javascript:void(0);\">'+ options.nextText +'</a></span>';
                if(options.lastShow) html += ' <span id="'+ options.lastId +'"><a href=\"javascript:void(0);\">'+ options.lastText +'</a></span>';
                html += options.controlsAfter;                      
                $(obj).after(html);                                     
            };

            $("a","#"+options.nextId).click(function(){     
                animate("next",true);
            });
            $("a","#"+options.prevId).click(function(){     
                animate("prev",true);               
            }); 
            $("a","#"+options.firstId).click(function(){        
                animate("first",true);
            });             
            $("a","#"+options.lastId).click(function(){     
                animate("last",true);               
            });     

            function animate(dir,clicked){
                var ot = t;             
                switch(dir){
                    case "next":
                        t = (ot>=ts) ? (options.continuous ? 0 : ts) : t+1;                     
                        break; 
                    case "prev":
                        t = (t<=0) ? (options.continuous ? ts : 0) : t-1;
                        break; 
                    case "first":
                        t = 0;
                        break; 
                    case "last":
                        t = ts;
                        break; 
                    default:
                        break; 
                };  

                var diff = Math.abs(ot-t);
                var speed = diff*options.speed;                     
                if(!options.vertical) {
                    p = (t*w*-1);
                    $("ul",obj).animate(
                        { marginLeft: p }, 
                        speed
                    );              
                } else {
                    p = (t*h*-1);
                    $("ul",obj).animate(
                        { marginTop: p }, 
                        speed
                    );                  
                };

                if(!options.continuous && options.controlsFade){                    
                    if(t==ts){
                        $("a","#"+options.nextId).hide();
                        $("a","#"+options.lastId).hide();
                    } else {
                        $("a","#"+options.nextId).show();
                        $("a","#"+options.lastId).show();                   
                    };
                    if(t==0){
                        $("a","#"+options.prevId).hide();
                        $("a","#"+options.firstId).hide();
                    } else {
                        $("a","#"+options.prevId).show();
                        $("a","#"+options.firstId).show();
                    };                  
                };              

                if(clicked) clearTimeout(timeout);
                if(options.auto && dir=="next" && !clicked){;
                    timeout = setTimeout(function(){
                        animate("next",false);
                    },diff*options.speed+options.pause);
                };

            };
            // init
            var timeout;
            if(options.auto){;
                timeout = setTimeout(function(){
                    animate("next",false);
                },options.pause);
            };      

            if(!options.continuous && options.controlsFade){                    
                $("a","#"+options.pr开发者_JS百科evId).hide();
                $("a","#"+options.firstId).hide();              
            };              

        });

    };

})(jQuery);

And function which i am trying of call is "animate" my function call is here

animate("next",false);

Can you guide me how to make proper function call?

---

How about this work around:

$('#nextBtn a').click();

And

$('#prevBtn a').click();

Works like a charm (assuming you have not altered the CSS Ids of the next/prev button elements)