title: Can i set float128 as the standard float-array in numpy
body: <p>So I have a problem with my numerical program, and I'm curious about whether it is a precision problem (i.e. round-off error). Is there a quick way to change all the float arrays in my program into <code>float128</code> arrays, without going through my code and typing <code>dtype='float128'</code> all over the place. My arrays are all float64, but i never explicitly wrote <code>dtype='float64'</code>, so i was hoping there was a way to change this default behavior.</p>