Merge 088522a into 48449c0

docs/usage.rst

@@ -2,6 +2,30 @@
 Usage
 =====
 
-To use deflex in a project::
+THIS CHAPTER IS WORK IN PROGRESS...
+
+.. contents::
+    :depth: 2
+    :local:
+    :backlinks: top
+
+DeflexScenario
+++++++++++++++
+
+The scenario class DeflexScenario is a central element of a deflexletzte
+
+In deflex all input data is stored as a dictionary of pandas ``DataFrame`` in
+the ``table_collection`` attribute of the ``DeflexScenario`` class.
+
+[TODO: add reference to DeflexScenario]
+
+At the moment, there are two methods to populate this attribute from a file:
+
+* read_csv() - to read a directory with all needed csv files.
+* read_excel() - to read a spread sheet.
+
+[TODO: only xlsx is possible, so xlsx is better than excel because it works for
+Libreoffice, too.]
+
+...
 
-	Coming soon