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# joelpt/squirt.js

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

### pokatomnik commented Apr 14, 2021

Such a nice function name!