Continuous functions

From JSXGraph Wiki
Revision as of 19:01, 7 January 2019 by A WASSERMANN (talk | contribs)
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

References

The underlying JavaScript source code

 var board = JXG.JSXGraph.initBoard('box', {boundingbox: [-6, 6, 6, -4], axis: true});
 board.suspendUpdate();

 var f = function(x) {
       if (x<1) {
          return 0.5*x*x;
       } else {
         return x+1;
       }
      };
 var graph = board.create('functiongraph', [f], {strokeColor:'#0000ff'});

 var s = board.create('slider', [[0,-1],[4,-1],[0,1,1]],{name:'&delta;'});

 var x1 = board.create('glider', [-2,0,board.defaultAxes.x],{name:'a'});
 board.suspendUpdate();
 var x2 = board.create('point', [function(){return x1.X()-s.Value();},0],{size:2,face:'[]',name:' '});
 var x3 = board.create('point', [function(){return x1.X()+s.Value();},0],{size:2,face:'[]',name:' '});
 var y1 = board.create('point', [function(){return x1.X();},function(){return f(x1.X());}],{size:2,face:'[]',name:'f(a)'});
 var y2 = board.create('point', [function(){return x2.X();},function(){return f(x2.X());}],{size:2,face:'[]',name:' '});
 var y3 = board.create('point', [function(){return x3.X();},function(){return f(x3.X());}],{size:2,face:'[]',name:' '});
 var v1 = board.create('segment', [x1,y1],{strokeColor:'gray',dash:2,strokeWidth:1});
 var v2 = board.create('line', [x2,y2],{strokeColor:'gray',dash:2,strokeWidth:1});
 var v3 = board.create('line', [x3,y3],{strokeColor:'gray',dash:2,strokeWidth:1});

 var h1 = board.create('curve', [function(t){return t},function(t){return y1.Y();}], {strokeColor:'gray',dash:2,strokeWidth:1});
 var h2 = board.create('curve', [function(t){return t},function(t){return y2.Y();}], {strokeColor:'gray',dash:2,strokeWidth:1});
 var h3 = board.create('curve', [function(t){return t},function(t){return y3.Y();}], {strokeColor:'gray',dash:2,strokeWidth:1});

 var txt = board.create('text', [4.2, -1.5, function() {
            return '&epsilon; = ' + Math.max(Math.abs(y2.Y() - y1.Y()), Math.abs(y1.Y() - y3.Y())).toFixed(5); 
           }], {strokeColor: 'blue'});
 board.unsuspendUpdate();