time duration

Time duration needs to be a power of 2. Not sure why yet. This is the error message.

/Users/jpowell/anaconda2/lib/python2.7/site-packages/tupak/gw/detector.py:1164: RuntimeWarning: invalid value encountered in multiply
  frequency_domain_strain = interpolated_power_spectral_density ** 0.5 * white_noise
15:59 WARNING : Injecting signal outside segment, start_time=1126259639.41, merger time=1126259642.41.
Traceback (most recent call last):
  File "BNS_test.py", line 50, in <module>
    sampling_frequency=sampling_frequency, outdir=outdir) for name in ['H1', 'L1']]
  File "/Users/jpowell/anaconda2/lib/python2.7/site-packages/tupak/gw/detector.py", line 1397, in get_interferometer_with_fake_noise_and_injection
    waveform_generator=waveform_generator)
  File "/Users/jpowell/anaconda2/lib/python2.7/site-packages/tupak/gw/detector.py", line 792, in inject_signal
    signal_ifo = self.get_detector_response(injection_polarizations, parameters)
  File "/Users/jpowell/anaconda2/lib/python2.7/site-packages/tupak/gw/detector.py", line 727, in get_detector_response
    signal_ifo *= self.strain_data.frequency_mask
ValueError: operands could not be broadcast together with shapes (8193,) (5121,) (8193,)