doc: Elaborate on selection of water levels.

* doc/fullswof-utils.texi (Theory): Add description of set of levels.

1 files changed, 7 insertions, 6 deletions

diff --git a/doc/fullswof-utils.texi b/doc/fullswof-utils.texi
index 03e5e9d..b98e587 100644
--- a/doc/fullswof-utils.texi
+++ b/doc/fullswof-utils.texi
@@ -430,12 +430,13 @@ Discharge and slope are then related by the expression
   @math{Q = K S@sup{1/2}}.
 @end indentedblock
 
-In order to generate data for the rating curve the conveyance and
-discharge are calculated for a set of water levels within the minimum to
-maximum range.  At each level the wetted perimeter and the
-cross-sectional area are calculated.  From these values the hydraulic
-radius is calculated, allowing the conveyance to be determined.
-Finally, the discharge is calculated from the conveyance.
+In order to generate data for the rating curves the conveyance and
+discharge are calculated for a set of water levels for each panel.  The
+set of levels spans the range between the minimum height and the maximum
+height.  At each level the wetted perimeter and the cross-sectional area
+are calculated.  From these values the hydraulic radius is calculated,
+allowing the conveyance to be determined.  Finally, the discharge is
+calculated from the conveyance.
 
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