import numpy as np

def xa_to_dia(xa):
    '''
    Convert an array of cross-sectional areas to diameters wih units
    '''

    diameter = np.sqrt(xa *4 / np.pi)
    return diameter

a = np.array([[6.7,1.3, 0.6, 0.7],
                [0.1, 5.5, 0.4, 2.4],
                [1.1, 0.8, 4.5, 1.7],
                [1.5, 1.5, 3.4, 7.5]])
b = np.array([1.1, 2.3, 3.3, 3.9])

import numpy as np

def xa_to_dia(xa):
    '''
    Convert an array of cross-sectional areas to diameters wih units
    '''

    diameter = np.sqrt(xa *4 / np.pi)
    return diameter

a = np.array([[6.7,1.3, 0.6, 0.7],
                [0.1, 5.5, 0.4, 2.4],
                [1.1, 0.8, 4.5, 1.7],
                [1.5, 1.5, 3.4, 7.5]])
b = np.array([1.1, 2.3, 3.3, 3.9])

Convert an array of cross-sectional areas to diameters wih units