Should g, n and (none) format types use exponent notation based on precision? about d3-format

[mbostock]

Slight correction: the threshold should be based on rounding. So for precision = 3, the threshold is 0.000995:

var f = format(".3n");
f(999.0); // "999"
f(999.9); // "1.00e+3"
f(0.9999); // "0.999"
f(0.09999); // "0.100"
f(0.009999); // "0.010"
f(0.0009999); // "0.001"
f(0.0009990); // "9.99e-4"

Maybe? Eh, this is a pain.

[mbostock]

Probably better to leave as-is unless we can figure out an easily-explained alternative. The precedent set by number.toPrecision is strong.