Two Nurbs Surface Merge To One Nurbs Surface

Hello! everyone, two quadrilateral plane(nurbs surface) degree=1 in u-direction and v-direction, they merge to one nurbs surface,the merged surface degree=1.
if a10=b00 and a11=b01,Does this mean that a nurbs surface is merged?

//Joann

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If the resulting surface after merge becomes a (single) surface, then it’s merged. If it’s still a polysurface after an attempt to merge, it wasn’t merged (it’s then only Joined).

Fig 1. Polysurface = not merged
image

// Rolf

Thanks! Rolf.Thank you for your reply.