How to define regular longitudes depending on irregular longitudes?

[chrisdane]

constructing regular lon,lat coords via

    xlim <- range(xp)
    ylim <- range(yp)
    x_len <- diff(xlim)
    y_len <- diff(ylim)
    xi = seq(xlim[1]+regular_dx/2, xlim[2]-regular_dx/2, l=x_len/regular_dx)
    yi = seq(ylim[1]+regular_dy/2, ylim[2]-regular_dy/2, l=y_len/regular_dy)

yields for mesh /mnt/lustre02/work/ab0995/a270046/meshes_default/core

   min/max xc_global[1,] = -180/180
   min/max xc_global[2,] = -180/180
   min/max xc_global[3,] = -180/180
   min/max yc_global[1,] = -78.4708041447/89.9579874093014
   min/max yc_global[2,] = -78.5169561104/89.9579874093014
   min/max yc_global[3,] = -78.5169561104/89.9579874093014

the number of regular lon,lat coords

        nxi = 1440 ;
        nyi = 674 ;

and for mesh /mnt/lustre02/work/ab0246/a270064/meshes/CORE2_lgmf

   min/max xc_global[1,] = -180/180
   min/max xc_global[2,] = -180/180
   min/max xc_global[3,] = -180/180
   min/max yc_global[1,] = -77.7648159206373/89.9579874092754
   min/max yc_global[2,] = -77.7922588421255/89.9579874092754
   min/max yc_global[3,] = -77.7922588421255/89.9579874092754

these

        nxi = 1440 ;
        nyi = 672 ;

How to solve this?