-We define c for a tempo ramp by placing a new tempo at some distance t away from our existing one.
-The problem is that we usually don't know t.
-We do know the duration in beats where the next tempo section lies.
-Where t = a (when we define c), we can solve a in terms of beat duration b and the two relevant tempos using the beat function:
-a = b log (Ta / T0) / (T0 (e^(log (Ta / T0)) - 1))
+The time t at which Tempo T occurs is a as above:
+t(T) = log(T / T0) / c
+
+We define c for this tempo ramp by placing a new tempo section at some time t after this one.
+Our problem is that we usually don't know t.
+We usually do know the duration in beats between this and the next tempo section.
+Where t = a (i.e. when a is equal to the time of the next tempo section), we can solve t in terms of
+beat duration and our two tempos.
+A bit of scribbling with the beat function gives us:
+t = b log (Ta / T0) / (T0 (e^(log (Ta / T0)) - 1))