If the input is a waveform, this is easy.
You can apply a 'Slope' channel process to the signal. Right-click the channel and choose "Channel Process...", then from the drop down list that probably has Rectify as the default setting, select Slope and click Add. Set an appropriate time constant (period over which to smooth the slope before and after each point).
This will cause the channel to be displayed as a slope and change the channel units appropriately, e.g. from Degrees to Degrees/s. Note that the channel itself is not changed, just the way it is displayed.
If you want a 'New' channel as slope, you can Duplicate the channel first (Right-click the channel, select the first item in the pop-up list 'Channel n' and the choose Duplicate, then add Slope to the channel, as above. If you want a permanent copy of the Slope, you can Right-click and select CHannel n, then select Save channel... and so on. These commands are also available in the Analysis menu.
You can use Virtual channels to do channel arithmetic (e.g. product, sum, differences, ratio of channels and other channel manipulations), you will find details of this in the Help.
Greg Smith Cambridge Electronic Design