fix description and picture link

Author: mtezzele

docs/source/_tutorials/pictures/transformations.png

@@ -11780,7 +11780,7 @@ <h2 id="Tutorial-3:-Prepare-a-blade-3D-sectional-profiles">Tutorial 3: Prepare a
 <div class="inner_cell">
 <div class="text_cell_render border-box-sizing rendered_html">
 <p>The foil transformations according to the pitch, rake, and skew are all given in the following transformations map.</p>
-<p><img src="data/transformations.png"></p>
+<p><img src="pictures/transformations.png" alt=""></p>
 
 </div>
 </div>

docs/source/_tutorials/tutorial3generateblade.html

@@ -9,12 +9,24 @@ Welcome to BladeX's documentation!
 Description
 ^^^^^^^^^^^^
 
-BladeX is a Python package for blade generation.
+BladeX is a Python package for geometrical parametrization and bottom-up construction of propeller blades. It allows to generate and deform a blade based on the radial distribution of its parameters such as pitch, rake, skew, and the sectional foils' parameters such as chord and camber. The package is ideally suited for parametric simulations on large number of blade deformations. It provides an automated procedure for the CAD generation, hence reducing the time and effort required for modelling. The main scope of BladeX is to deal with propeller blades, however it can be flexible to be applied on further applications with analogous geometrical structures such as aircraft wings, turbomachinery, or wind turbine blades.
 
 
-Installation
---------------------
-BladeX requires numpy, scipy, matplotlib, and sphinx (for the documentation). They can be easily installed via pip. 
+Dependencies and installation
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+BladeX requires numpy, scipy, matplotlib, sphinx (for the documentation), and nose (for the local test). They can be easily installed using pip.
+
+BladeX is compatible with Python 2.7 and Python 3.6. Moreover, some of the modules require OCC to be installed for the .iges or .stl CAD generation. Please see below for instructions on how to satisfy the OCC requirements. You can also refer to `pythonocc.org <https://pythonocc.org>`_ or `github.com/tpaviot/pythonocc-core <https://github.com/tpaviot/pythonocc-core>`_ for further instructions. 
+
+Python2.7 OCC installation:
+::
+
+  conda install -c conda-forge -c dlr-sc -c pythonocc -c oce pythonocc-core==0.18.1 python=2.7
+
+Python3.6 OCC installation:
+::
+
+  conda install -c conda-forge -c dlr-sc -c pythonocc -c oce pythonocc-core==0.18.1 python=3.6
 
 
 The `official distribution <https://github.com/mathLab/BladeX>`_ is on GitHub, and you can clone the repository using
@@ -36,7 +48,7 @@ To uninstall the package you have to rerun the installation and record the insta
 
 
 Tutorials
---------------------
+^^^^^^^^^^^^^^^^
 
 We made some tutorial examples. Please refer to the official GitHub repository for the last updates. Here the list of the exported tutorials:
 
@@ -47,7 +59,7 @@ We made some tutorial examples. Please refer to the official GitHub repository f
 
 
 Developer's Guide
---------------------
+^^^^^^^^^^^^^^^^^^^^^^^
 
 .. toctree::
    :maxdepth: 1