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探祕 JavaScript 世界的神祕數字 1.7976931348623157e+308
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11 位，如果全部爲 1，則最大能夠表示 ","attrs":{}},{"type":"katexinline","attrs":{"mathString":"2^{11} - 1 = 2047"}},{"type":"text","text":"。所以指數的範圍是 [0, 2047]。但是指數部分有負數，所以定義了一個","attrs":{}},{"type":"link","attrs":{"href":"https://en.wikipedia.org/wiki/Exponent_bias","title":"","type":null},"content":[{"type":"text","text":"偏移量","attrs":{}}]},{"type":"text","text":"，在 64 位浮點數中，偏移量爲 1023（ ","attrs":{}},{"type":"katexinline","attrs":{"mathString":"2^e - 1"}},{"type":"text","text":"，","attrs":{}},{"type":"katexinline","attrs":{"mathString":"e"}},{"type":"text","text":" 爲 ","attrs":{}},{"type":"katexinline","attrs":{"mathString":"11"}},{"type":"text","text":")。減去偏移量之後，指數的範圍變成了 ","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"[-1023, 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