Difference between revisions of "Dual lattice"
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A WASSERMANN (talk | contribs) |
A WASSERMANN (talk | contribs) |
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<jsxgraph height="500" width="500" board="board" box="box1"> | <jsxgraph height="500" width="500" board="board" box="box1"> | ||
| − | brd = JXG.JSXGraph.initBoard('box1', {boundingbox: [-5, 5, 5, -5], axis: | + | brd = JXG.JSXGraph.initBoard('box1', {boundingbox: [-5, 5, 5, -5], axis:false}); |
| − | var b1 = brd.create('point', [4,0], {size:6, name:'', color:'blue'}), | + | var b1 = brd.create('point', [4,0], {size:6, name:'1', color:'blue', snaptogrid: true}), |
| − | b2 = brd.create('point', [3,3], {size:6, name:'', color:'blue'}), | + | b2 = brd.create('point', [3,3], {size:6, name:'2', color:'blue', snaptogrid: true}), |
| − | v1 = brd.create('arrow', [[0,0], b1], {}), | + | v1 = brd.create('arrow', [[0,0], b1], {strokeColor: 'black'}), |
| − | v2 = brd.create('arrow', [[0,0], b2], {}); | + | v2 = brd.create('arrow', [[0,0], b2], {strokeColor: 'red'}), |
| + | w1, w2, i, j; | ||
| + | |||
| + | for (i=-5;i<6;i++) for (j=-5;j<6;j++) { | ||
| + | if (!(i==1&&j==0) && !(i==0&&j==1)) { | ||
| + | brd.create('point',[ | ||
| + | function(x,y){ return function(){ return x*b1.X()+y*b2.X(); };}(i,j), | ||
| + | function(x,y){ return function(){ return x*b1.Y()+y*b2.Y(); };}(i,j) | ||
| + | ], {name:'', size:2}); | ||
| + | }} | ||
| + | |||
| + | w1 = brd.create('arrow', [[0,0], function() { | ||
| + | var num = b1.X() * b2.Y() - b2.X() * b1.Y(); | ||
| + | return [b2.Y() / num, -b2.X() / num]; | ||
| + | }], {strokeColor: 'black', name:"1'", withLabel:true, label:{position:'rt'}}); | ||
| + | |||
| + | w2 = brd.create('arrow', [[0,0], function() { | ||
| + | var num = b1.X() * b2.Y() - b2.X() * b1.Y(); | ||
| + | return [-b1.Y() / num, b1.X() / num]; | ||
| + | }], {strokeColor: 'red', name:"2'", withLabel:true, label:{position:'rt'}}); | ||
