import numpy as np
 
def _mlinedata(np_array):
    """
    Used when mulitply of splited line data
    """
    height, width = np_array.shape
    x_line = np.linspace(0, width-1, width)
    y_line = np.linspace(0, height, height)
    return x_line, y_line
 
def _slope(value, slope_coeff=(0.5, 1)):
    """
    slope_coeff = (position, slope)\n
    position: 0 ~ 1 ratio\n
    slope: dimensionless
    """
    point_index = int(len(value)*slope_coeff[0])
    value[point_index:] *= slope_coeff[1]
    return value
 
def slope(Zdata_array, x_slope_coeff=(0,0.01), y_slope_coeff=(0,0.01)):
    """
    slope_coeff = (position, slope)\n
    position: 0 ~ 1 ratio\n
    slope: dimensionless
    """
    x_line, y_line = _mlinedata(Zdata_array)
    dist_x = _slope(x_line,x_slope_coeff)
    dist_y = _slope(y_line,y_slope_coeff)
    mx, my = np.meshgrid(dist_x,dist_y)
    return Zdata_array + mx + my