prevPow2 - nodef/extra-bigint GitHub Wiki

Find largest power-of-2 less than or equal to given bigint.

Similar: prevPow2, prevPow10. Similar: isPow2, prevPow2, nextPow2.

function prevPow2(x)
// x: a bigint
const xbigint = require('extra-bigint');


xbigint.prevPow2(32n);
// → 32n

xbigint.prevPow2(1023n);
// → 512n

References