Difference between revisions of "Convergence of sequence"
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| Line 3: | Line 3: | ||
<html> | <html> | ||
<p> | <p> | ||
| − | nth-element of the sequence: <input type="text" id="input" value="1 / n" | + | nth-element of the sequence: <input type="text" id="input" value="1 / n"> |
| − | start at <input type="number" id="startval" value="1" style="width:2em"> | + | start at <input type="number" id="startval" value="1" style="width:2em"><br /> |
<input type="button" value="start" onClick="start_approx()"> | <input type="button" value="start" onClick="start_approx()"> | ||
<input type="button" value="stop" onClick="clear_all()"> | <input type="button" value="stop" onClick="clear_all()"> | ||
| Line 10: | Line 10: | ||
<jsxgraph width="500" height="500" box="box"> | <jsxgraph width="500" height="500" box="box"> | ||
var board = JXG.JSXGraph.initBoard('box', {axis:true, boundingbox: [-3, 8, 50, -8]}); | var board = JXG.JSXGraph.initBoard('box', {axis:true, boundingbox: [-3, 8, 50, -8]}); | ||
| − | var seq = board.create('curve', [[ | + | var seq = board.create('curve', [[], []], {strokeColor: 'blue'}); |
| − | + | var n; | |
| + | |||
var seq_add = function() { | var seq_add = function() { | ||
| − | var | + | var val = a_n(n); |
| − | |||
seq.dataX.push(n); | seq.dataX.push(n); | ||
seq.dataY.push(val); | seq.dataY.push(val); | ||
| + | n++; | ||
}; | }; | ||
| Line 26: | Line 27: | ||
seq_add(); | seq_add(); | ||
board.update(); | board.update(); | ||
| − | if ( | + | if (n <= 50) { |
TO = setTimeout(approx, 500); | TO = setTimeout(approx, 500); | ||
} | } | ||
| Line 35: | Line 36: | ||
var txtraw = document.getElementById('input').value; | var txtraw = document.getElementById('input').value; | ||
a_n = board.jc.snippet(txtraw, true, 'n', true); | a_n = board.jc.snippet(txtraw, true, 'n', true); | ||
| + | n = document.getElementById('startval').value; | ||
approx(); | approx(); | ||
} | } | ||
| Line 40: | Line 42: | ||
var clear_all = function() { | var clear_all = function() { | ||
clearTimeout(TO); | clearTimeout(TO); | ||
| − | seq.dataX = [ | + | seq.dataX = []; |
| − | seq.dataY = [ | + | seq.dataY = []; |
| + | n = 0; | ||
}; | }; | ||
| Line 49: | Line 52: | ||
<source lang="javascript"> | <source lang="javascript"> | ||
var board = JXG.JSXGraph.initBoard('box', {axis:true, boundingbox: [-3, 8, 50, -8]}); | var board = JXG.JSXGraph.initBoard('box', {axis:true, boundingbox: [-3, 8, 50, -8]}); | ||
| − | var seq = board.create('curve', [[ | + | var seq = board.create('curve', [[], []], {strokeColor: 'blue'}); |
var seq_add = function() { | var seq_add = function() { | ||
Revision as of 19:46, 7 January 2019
Compute values of the sequence [math] (a_n)_{n\in{\mathbb N}}[/math].
nth-element of the sequence:
start at
The underlying JavaScript code
var board = JXG.JSXGraph.initBoard('box', {axis:true, boundingbox: [-3, 8, 50, -8]});
var seq = board.create('curve', [[], []], {strokeColor: 'blue'});
var seq_add = function() {
var n = seq.dataX.length,
val = a_n(n);
seq.dataX.push(n);
seq.dataY.push(val);
};
var txt1 = board.create('text', [15, 1.6, function() { return 'n=' + (seq.dataX.length-1) + ': value = ' + seq.dataY[seq.dataY.length - 1]; }], {strokeColor: 'blue'});
var TO;
var approx = function() {
seq_add();
board.update();
if (seq.dataX.length <= 50) {
TO = setTimeout(approx, 500);
}
};
var a_n;
var start_approx = function() {
var txtraw = document.getElementById('input').value;
a_n = board.jc.snippet(txtraw, true, 'n', true);
approx();
}
var clear_all = function() {
clearTimeout(TO);
seq.dataX = [0];
seq.dataY = [1];
};
