Python: float()参数必须是字符串或数字，而不是'interp2d'

this code returns the error "float() argument must be a string or a number, not 'interp2d'". I'm attempting to learn how to interpolate values to fill an array given a few of the values in the array (sorry, bad phrasing). Am I messing up the syntax for the interp2d function or what?this code returns the error "float() argument m