fixes documentation conf syntax

CMakeLists.txt

@@ -47,7 +47,11 @@ endif()
 
 project(TurTLE)
 
-execute_process(COMMAND python3 ${PROJECT_SOURCE_DIR}/get_version.py OUTPUT_VARIABLE TURTLE_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+find_program(PYTHON_EXECUTABLE
+             python3)
+
+execute_process(COMMAND ${PYTHON_EXECUTABLE} ${PROJECT_SOURCE_DIR}/get_version.py OUTPUT_VARIABLE TURTLE_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
 
 project(TurTLE
         VERSION ${TURTLE_VERSION}
@@ -484,7 +488,7 @@ else()
         install(CODE "execute_process(COMMAND ${CMAKE_COMMAND} -E copy ${PROJECT_SOURCE_DIR}/pc_host_info.py ${PROJECT_BINARY_DIR}/python/TurTLE/host_info.py)")
     endif()
 endif()
-install(CODE "execute_process(COMMAND python3 ${PROJECT_SOURCE_DIR}/setup.py install --force --prefix=${CMAKE_INSTALL_PREFIX} WORKING_DIRECTORY ${PROJECT_BINARY_DIR}/python/)")
+install(CODE "execute_process(COMMAND ${PYTHON_EXECUTABLE} ${PROJECT_SOURCE_DIR}/setup.py install --force --prefix=${CMAKE_INSTALL_PREFIX} WORKING_DIRECTORY ${PROJECT_BINARY_DIR}/python/)")
 
 
 #####################################################################################

documentation/conf.py.in

@@ -142,7 +142,7 @@ latex_elements = {
 #'pointsize': '10pt',
 
 # Additional stuff for the LaTeX preamble.
-'preamble': '\usepackage{amssymb,amsmath,amsfonts}',
+'preamble': '\\usepackage{amssymb,amsmath,amsfonts}',
 
 # Latex figure (float) alignment
 #'figure_align': 'htbp',