Map projection doesn't work in Matlab2015a?

Hi,

I have lat (37x73), lon(37x73) and a rainfall data(37x73). I plotted the rainfall data (attached) on map with robinson projection. However, it seems there is blanck space (I mean it is not covering the globe completely, see attched plot) although lat(-90 to 90), lon(0 to 360) and corresponding data show global coverage. I really don't know the reason. Am I doing something wrong?? Thank you so much.

my code is below

ann=importdata('rain.txt');
x1=0:5:360;%lon
y1=-90:5:90;%lat
x2=repmat(x1,37,1);
y2=repmat(y1',1,73);
%%if lon>180,west longitude
[ay,ny]=find(x2>180);x2(ay)=x2(ay)-360; 
%%%%plot data on globe
landareas = shaperead('landareas.shp','UseGeoCoords',true);
axesm ('robinson', 'Frame', 'on', 'Grid', 'on');set(gca, 'color', 'none');
surfm(y2,x2,ann);geoshow(landareas,'FaceColor','none','EdgeColor',[1 1 1]);

[Madan Kumar]

Solved it. longitude -180 was zero (=360-360)when substracting from 360.