Interpolated texture access using tex2D

Hi, I have a question regarding texture access based on the function tex2D. I have a piece of code which uses this function to access the pixels of an image. In general the code is working fine but it seems that it does not use interpolation.
In the CUDA Programming guide I can only find the description “When enabled … bilinear interpolation is performed for two-dimensional textures” (chapter 4.3.4.2 in Guide v2.1). How do I enable it or check whether the interpolation is enabled?

Thanks in advance for your help!

Cat

Search for filterMode and cudaFilterModeLinear in the Programming Guide.