SDX Interest Rates lets you price a single leg of a vanilla swap. For this single leg you can specify whether it is a fixed leg or a floating leg, and whether you are a payer or a receiver.
Being able to price a single leg is useful as it:
Lets you price simple cash flow structures.
Lets you model fixed or floating rate bonds.
Provides a mechanism for you to model a loan transaction.
Pricing a Single Leg of a Vanilla Swap in SDX Interest Rates
You can only price a single leg of a vanilla swap in the Portfolio page, not in the Single Option page.