len(arange(0.60,0.70,0.01))

array([0.60, ... ,0.69])

len(arange(0.60,0.80,0.01))

array([0.60, ... , 0.79, 0.80])

array([ 0.6 ,  0.61,  0.62,  0.63,  0.64,  0.65,  0.66,  0.67,  0.68,  0.69])