How do I code normalized global errors in Matlab?

If I is defined to be a discrete approximation to the global integral then

I(h)=\frac{1}{4\pi} \int_{0}^{2\pi}\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}}h(\lambda,\theta)\cos{\theta} {d\theta} d\lambda
I need help on how to write a Matlab code for the following normalized global errors:

l_{1}(h)=\frac{I[|h(\lambda, \theta)-h_{T}(\lambda, \theta)|]}{I[|h_{T}(\lambda, \theta)|]}

l_{2}(h)=\frac{\{I[(h(\lambda, \theta)-h_{T}(\lambda, \theta))^2]\}^{1/2}}{\{I[h_{T}(\lambda, \theta)^2]\}^{1/2}}

l_{\infin}(h)=\frac{\max_{all\lambda,\theta}|h(\lambda, \theta)-h_{T}(\lambda, \theta)|}{\max_{all\lambda,\theta}|h_{T}(\lambda, \theta)|}
where h_{T} is the true solution.