work--surface domain management hintan example may help with regards to what ' asking for with respect to the - arrays if lon= arange( and lat= arange( )then the lonall instance attribute would be[[ [ [ [ ]and the latall instance attribute would be[[ [ [ [ ]solution and discussionthe two solutions described below (with the second solution commented outare in course files/code files in the file surface domain pyhere' the solution using for loops import numpy as class surfacedomain(object)def __init__(selflonlat)self lon array(lonself lat array(lat shape ( size(self lat) size(self lon)self _lonall zeros(shape ddtype=' 'self _latall zeros(shape ddtype=' 'for in xrange(shape [ ])for in xrange(shape [ ])self _lonall[ ,jself lon[jself _latall[ ,jself lat[ilines - guarantee that lon and lat are numpy arraysin case lists or tuples are passed in and here' simpler and faster solution using the meshgrid function in using numpy instead of the for loopsmeshgrid