发表于 2009-1-5 19:48
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javascript瀹炰緥鏁欑▼(16) 浣跨敤javascript鐨勬暟瀛﹀嚱鏁
鍙戝竷: 2008-6-27 09:53 | 浣滆: admin | 鏌ョ湅: 8娆
鍦↗avaScript涓紝鏁板鏂规硶鍙互鍒嗘垚浠ヤ笅鍑犵被锛歝onstans锛堝父鏁帮級銆乸ower functions锛堜箻鏂瑰嚱鏁帮級銆乼rigonometic functions锛堜笁瑙掑嚱鏁帮級銆乺ounding functions锛堣垗鍏ュ嚱鏁帮級浠ュ強random numbers锛堥殢鏈烘暟瀛楋級銆備笅闈㈤愪釜璇存槑锛
甯告暟鍜屼箻鏂瑰嚱鏁
Math.E
鑷劧瀵规暟鐨勫簳(涓哄父鏁)
2.718
Math.LN10
10鐨勮嚜鐒跺鏁
2.302
Math.LN2
2鐨勮嚜鐒跺鏁
0.693
Math.PI
鍦嗗懆鐜
3.1415
Math.SQRT1_2
1/2鐨勫钩鏂规牴
0.707
Math.SQRT2
2鐨勫钩鏂规牴
1.414
Math.sqrt(x)
X鐨勫钩鏂规牴
鏇碭鐨勫兼湁鍏
Math.pow(x, n)
杩斿洖x鐨刵娆℃柟鐨勬暟鍊
鍙傛暟涓簒鍜宯
Math.log(n)
杩斿洖n鐨勮嚜鐒跺鏁
鍙傛暟涓簄
Math.exp(n)
杩斿洖e鐨刵娆℃柟鐨勬暟鍊
鍙傛暟涓簄
涓夎鍑芥暟
Math.cos(x)
X鐨勪綑寮﹀嚱鏁
Math.sin(x)
X鐨勬寮﹀嚱鏁
Math.tan(x)
X鐨勬鍒囧嚱鏁
Math.acos(y)
X鐨勫弽浣欏鸡鍑芥暟
Math.asin(y)
X鐨勫弽姝ｅ鸡鍑芥暟
Math.atan(y)
X鐨勫弽姝ｅ垏鍑芥暟
杩欓噷娉ㄦ剰锛氬弬鏁皒鍜屼互鍙婂弽鍑芥暟鐨勮繑鍥炴暟鍊肩殑鍗曚綅閮戒负寮у害锛堟瘮濡 PI寮у害=180搴︼級
鑸嶅叆鍑芥暟鍜岄殢鏈烘暟瀛
Math.random()
浜х敓浠0鍒1鐨勯殢鏈烘暟
Math.round(x)
鍙栨渶鎺ヨ繎鏁存暟x鐨勬暟鍊
Math.floor(x)
鍙栨渶鎺ヨ繎鏁存暟x骞朵笖姣攛灏忕殑鏁板
Math.ceil(x)
鍙栨渶鎺ヨ繎鏁存暟x骞朵笖姣攛澶х殑鏁板
Math.min(a, b, c)
杩斿洖鍙傛暟鍒楄〃涓渶灏忕殑鏁板
Math.max(a, b, c)
杩斿洖鍙傛暟鍒楄〃涓渶澶х殑鏁板
杩欓噷娉ㄦ剰锛氬嚱鏁癕ath.random()鍙兘鍦║nix鐗堟湰鐨凬avigator 2.0鎵ц銆
杩欎簺鍑芥暟涓渶甯哥敤鐨勫氨鏄骇鐢熷湪缁欏畾涓や釜鏁板间箣闂寸殑闅忔満鏁般備互涓嬬殑鍑芥暟灏辨槸涓涓緢濂界殑渚嬪瓙锛
function randomvalue(low, high) {
alert(Math.floor(Math.random() * (1 + high - low) + low));
}
鍙﹀锛屼綘鍙互鍦ㄥ鏉傜殑浠ｇ爜涓娇鐢╳ith璇彞鏉ラ伩鍏峂ath鏍囪瘑绗︾殑閲嶅浣跨敤锛屼緥濡備互涓嬩唬鐮侊細
function randomvalue(low, high) {
with (Math) {
alert(floor(random() * (1 + high - low) + low));
}
}
杩欓噷瑕佽浣忥紝Math.random()鍑芥暟鍙兘鍦║nix鐗堟湰鐨凬avigator 2.0鎵ц锛岃屼笉鑳藉湪windows鐗堟湰鐨勬祻瑙堝櫒涓墽琛岋紝鎵浠ヨ繖涓嚱鏁版垜浠竴鑸笉浣跨敤銆
浠ヤ笅缁欏嚭鐨勬槸涓涓洿澶嶆潅鐨勫嚱鏁般傝繖涓嚱鏁拌繑鍥炰笁瑙掑舰绗笁杈圭殑闀垮害锛岀粰鍑虹殑鏉′欢鏄笁瑙掑舰鐨勪袱杈瑰強涓よ竟鐨勫す瑙掋傚叿浣撲唬鐮佸涓嬶細
function findside(sidea, sideb, angle) {
with (Math) {
var tmp = pow(sidea, 2) + pow(sideb, 2) - 2 * sidea * sideb * cos(angle)
