-
Notifications
You must be signed in to change notification settings - Fork 0
/
ComplexMultiplcation.htm
234 lines (183 loc) · 4.67 KB
/
ComplexMultiplcation.htm
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
<!DOCTYPE html>
<html>
<head>
<script>
function person(firstname,lastname,age,eyecolor)
{
this.firstname=firstname;
this.lastname=lastname;
this.age=age;
this.eyecolor=eyecolor;
}
person.prototype.changeName = function (name) {
this.lastname=name;
};
var myFather=new person("John","Doe",50,"blue");
var r = 1.0;
var i = 1.5;
var active = false;
var dragging = false;
function relMouseCoords(event){
var totalOffsetX = 0;
var totalOffsetY = 0;
var canvasX = 0;
var canvasY = 0;
var currentElement = this;
do{
totalOffsetX += currentElement.offsetLeft - currentElement.scrollLeft;
totalOffsetY += currentElement.offsetTop - currentElement.scrollTop;
}
while(currentElement = currentElement.offsetParent)
canvasX = event.pageX - totalOffsetX;
canvasY = event.pageY - totalOffsetY;
return {x:canvasX, y:canvasY}
}
HTMLCanvasElement.prototype.relMouseCoords = relMouseCoords;
function mouseMove(event)
{
var canvas = document.getElementById("myCanvas")
coords = canvas.relMouseCoords(event);
if (dragging) {
r = (coords.x - 200.0) / 100.0;
i = (200.0 - coords.y) / 100.0;
draw(true);
} else {
// transform the event to be relative to the canvas.
var tx = 200 + r*100.0;
var ty = 200 - i*100.0;
tx = tx - coords.x;
ty = ty - coords.y;
dist = tx * tx + ty * ty;
if (dist <= 25.0 && ! active) {
active = true;
draw(true);
}
if (dist > 25.0 && active) {
active = false;
draw(true);
}
}
}
function mouseDown(event)
{
if (active) {
dragging = true;
}
}
function mouseUp(event)
{
dragging = false;
}
function draw(dragable)
{
var c=document.getElementById("myCanvas");
var canvOK=1;
try {c.getContext("2d");}
catch (er) {canvOK=0;}
if (canvOK==1) {
var radius = Math.sqrt(r*r + i*i);
var theta = Math.atan2(i,r) * 180 / Math.PI;
if (theta < 0.0) {
theta += 360.0;
}
var ctx=c.getContext("2d");
ctx.clearRect ( 0 , 0 , 400 , 410 );
// Draw the unit circle.
ctx.beginPath();
ctx.arc(200,200,100,0,2*Math.PI);
ctx.strokeStyle="#A0A0A0";
ctx.stroke();
ctx.closePath();
// Draw the Axes vector
ctx.beginPath();
ctx.moveTo(20,200);
ctx.lineTo(380,200);
ctx.strokeStyle="#000000";
ctx.stroke();
ctx.moveTo(200,20);
ctx.lineTo(200,380);
ctx.strokeStyle="#000000";
ctx.stroke();
ctx.closePath();
// Draw the complex vector
ctx.beginPath();
ctx.moveTo(200,200);
ctx.lineTo(200 + r*100.0,200 - i*100.0);
ctx.strokeStyle="#0000AF";
ctx.stroke();
ctx.closePath();
// Draw the angle theta arc.
ctx.beginPath();
ctx.strokeStyle="#FF0000";
ctx.arc(200,200,20,-theta * Math.PI/ 180.0, 0.0);
ctx.stroke();
ctx.closePath();
if (dragable) {
// Active end spot
ctx.beginPath();
ctx.arc(200 + r*100.0,200 - i*100.0,5,0,2*Math.PI);
ctx.closePath();
if (active) {
ctx.fillStyle="#FFFF00";
} else {
ctx.fillStyle="#FF0000";
}
ctx.fill();
} else {
// Draw an arrow tip.
ctx.beginPath();
var tx = 200 + r*100.0;
var ty = 200 - i*100.0;
// Tip is origin. end point of barb.
var x = -20;
var y = +10;
// sin and cos from normalized complex vector
s = -i/radius; // Rotation is opposite because y is flipped.
c = r/radius;
// Rotate barb
var t1x = tx + x*c - y*s;
var t1y = ty + x*s + y*c;
var t2x = tx + x*c + y*s;
var t2y = ty + x*s - y*c;
// draw the barb
ctx.beginPath();
ctx.moveTo(tx,ty);
ctx.lineTo(t1x,t1y);
ctx.stroke();
ctx.moveTo(tx,ty);
ctx.lineTo(t2x,t2y);
ctx.stroke();
ctx.closePath();
}
// Draw the complex coordinates label
ctx.font="30px Arial";
var coordStr = "";
ctx.fillStyle="#0000AF";
coordStr = coordStr + r.toFixed(1);
coordStr = coordStr + " + ";
coordStr = coordStr + i.toFixed(1) + "i";
ctx.fillText(coordStr,5,30);
// Draw the polar coordinates
var coordStr = "Radius: ";
coordStr = coordStr + radius.toFixed(1);
coordStr = coordStr + ", Theta: ";
coordStr = coordStr + theta.toFixed(1);
ctx.font="20px Arial";
ctx.fillStyle="#0000AF";
ctx.fillText(coordStr,5,405);
}
}
function main()
{
draw(true);
}
</script>
<body onload="main()">
<canvas id="myCanvas" width="400" height="410" style="border:1px solid #d3d3d3;"
onmousemove="mouseMove(event)"
onmousedown="mouseDown()"
onmouseup="mouseUp()"
>
Your browser does not support the HTML5 canvas tag.</canvas>
</body>
</html>