Created
October 2, 2012 23:41
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Manually calculate the square root of a number with Javascript
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// The Babylonian Method | |
// http://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method | |
// @param n - the number to compute the square root of | |
// @param g - the best guess so far (can omit from initial call) | |
function squirt(n, g) { | |
if (!g) { | |
// Take an initial guess at the square root | |
g = n / 2.0; | |
} | |
var d = n / g; // Divide our guess into the number | |
var ng = (d + g) / 2.0; // Use average of g and d as our new guess | |
if (g == ng) { | |
// The new guess is the same as the old guess; further guesses | |
// can get no more accurate so we return this guess | |
return g; | |
} | |
// Recursively solve for closer and closer approximations of the square root | |
return squirt(n, ng); | |
} | |
console.log(squirt(42)); // 6.48074069840786 |
Well done.
Such a nice function name!
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This is brilliant thank you