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26 lines
666 B
JavaScript
26 lines
666 B
JavaScript
/*
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A program to demonstrate the implementation of the signum function,
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also known as the sign function, in JavaScript.
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The signum function is an odd mathematical function, which returns the
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sign of the provided real number.
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It can return 3 values: 1 for values greater than zero, 0 for zero itself,
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and -1 for values less than zero
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Wikipedia: https://en.wikipedia.org/wiki/Sign_function
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*/
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/**
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* @param {Number} input
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* @returns {-1 | 0 | 1 | NaN} sign of input (and NaN if the input is not a number)
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*/
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function signum (input) {
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if (input === 0) return 0
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if (input > 0) return 1
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if (input < 0) return -1
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return NaN
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}
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export { signum }
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