Editing Tutorial (section)

===Creating an SConstruct===
Now that we have the three SConstruct commands, we can write our first SConstruct.  To do so, open the SConstruct file in your favorite text editor.  Before we can create any '''Flow''' , '''Plot'''  or '''Result'''  statements we have to add a first statement to the SConstruct.  Enter the following statement (verbatim) into your new SConstruct:
<pre>
from rsf.proj import *
</pre>
This statement tells SCons where to find the '''Flow''' , '''Plot'''  and '''Result'''  commands, and must be included in '''every'''  SConstruct.
After that statement has been entered, you can enter as many '''Flow''' , '''Plot'''  and '''Result'''  commands as you wish making sure to use proper syntax.  It's helpful to use a text editor that has Python syntax highlighting, as that will help you find and remedy strings that are not closed.  You can also create Python comments using the <math>\#</math> mark to indicate the beginning of a comment to help document your SConstructs.

Lastly, you must include the following statement at the end of your SConstruct:
<syntaxhighlight lang="python">
End()
</syntaxhighlight>
This statement tells SCons that the script is done and that it should not look for anything else in the script.  Make sure to include this statement as the very last item in every SConstruct. 
Here's a sample SConstruct:

<syntaxhighlight lang="python">
from rsf.proj import *  # Remember, this statement comes first... ALWAYS
Flow("spike",None,"sfspike n1=100 k1=50") 
# None is a trick, see Advanced SCons for more information
Flow("spike1","spike","sfadd scale=4.0")
Flow("noise","spike1","sfnoise")
Plot("spike",'sfgraph title="spike" ' ) # Note string nesting
Plot("spike1",'sfgraph title="spike1" ') 
Plot("noise",'sfgraph title="noisy" ')
Result("noise",'sfgraph title="noisy" pclip=75 ')
End() # Remember, this always ends the script.
</syntaxhighlight>
Note: you do not have to order your '''Flow''' , '''Plot'''  and '''Result'''  commands as shown above.  You can mix '''Flow''' , '''Plot'''  and '''Result'''  in any order.  SCons automatically establishes the relationships between related files and commands.