def emv(hl, volume, window=9, ma_type='sma', vol_divisor=1000):
'''EMV'''
high, low = utils.safe_hl(hl)
volume = utils.safe_series(volume)
mid = .5 * (high + low)
volume /= vol_divisor
rval = (mid - mid.shift(1)) / (volume / (high - low))
rval_ma = ma.get_ma(ma_type)(rval, window)
return pd.DataFrame(dict(emv=rval, maEMV=rval_ma), index=hl.index)
def sar(hl, accel=(0.02, 0.2), sig_init=-1, gap_init=1.):
high, low = utils.safe_hl(hl)
assert sig_init in [-1, 1]
assert gap_init > 0 and gap_init < 10
return fast.sar(high, low, accel[0], accel[1], sig_init, gap_init)
