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fm2x clients often create forms or questionnaires of considerable logical complexity (sample logic table). It is not unusual for the logic presented to be incomplete or incorrect. Network graphs are a convenient way of presenting logic back to clients for verification and validation.

Graphviz is open source software for generating diagrams of abstract graphs and networks. Although there is a python library, using it through dot, a command line generator, is simpler and easier to test. Here is how fm2x interfaced its tabular logic generator to create a network logic diagram:

#Typical dot syntax where question numbers are preceded with Q 
#Q1->Q2 [style=bold,fontsize=10]; Q1->Q2 [label="Q6=='1'"fontsize=10];
#Q1->Q3A [label="Q6=='2'",fontsize=10]; Q1->Q4 [label="Q6=='3'",fontsize=10];
#Q2->Q4 [style=bold]; Q3A->Q4 [style=bold]; Q4->Q8 [style=bold];
for type,name,qnid,prompt,code in r:
if type<>'page':continue;
for line in lines:
if code1[0]=="" and len(lines)>1:code1[0]="Default"
try: t+='''%s->%s [label="%s",fontsize=10];'''%(name,code1[1],code1[0]);
except: pass
dot='''digraph hierarchy {bgcolor=lightgoldenrod1; %s } '''%(t);
f=open(dotfile,'w'); f.write(dot);
command = '''echo '%s' |dot -Tpng -o %s '''%(dot,pngfile);
Then just provide access to the png file. Apologies, full file paths have been masked.
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