Contents

• Problem statement
• Motivation
• Features implemented
• Time break up
• Design details
• Implementation details
• Future work and Conclusion

Copyright © 2005-2006 W3C ^® (MIT, ERCIM, Keio), All Rights Reserved.

Problem Statement

To provide package for drawing flow diagram.This flow diagram is general and be used to draw various diagrams easily.

Input

The command named "mydia" should be used to draw the diagram.This diagram accepts two parameters in curly braces as:

1. Triplets of the form s/t/l

   S:Shape of node circular or rectangular
   t:Text to be written inside node
   l:Text to be written on edge
   Triplets should be seperated by comma.

2. N
   Number of triplets

Output

The Tikz diagram generated according to given description. The diagram has given number of nodes. The nodes can be circular or rectangular.The inputed text is written inside each node.The third parameter for each triplet should be text to be written on ege which will be incident onto this node. The placement of nodes is done automatically and assumes circular shape.The default arrow shape is drawn between two nodes as "->".

Sample diagram generated:Lifecycle of butterfly is :

Sample line from .tex file to draw diagram:


  \mydia{placep/Process1/,rect/External Entity/,placep/Process2/}{3}

Motivation

The reasons for selecting this as miniproject are as follows:

• There are many domains such as medical,management,economics,pure sciences,engineering.In all these areas,we usually come across many concepts. We can explain such concepts very easily if we take help of some simple diagrams as compared to just plain text. Also to depict the flow or dependency between two concepts,entities diagrams provide visual aid.As not everybody is well acquainted with drawing tools and languages such as Tikz, if readymade functions are available to draw such diagram it will save time.
  e.g. to draw a diagram by saying draw circle or other shapes and then doing calculations to place them and use all the commands to make that diagram look better can take time. Instead calling one function and sending required parameters is easy and it suffices even if user does not have enough knowlege.

  So I selected to provide basic command which can be generic enogh to draw such simple diagrams for people in other domains.So diagrams drawn as per requirement can be used while presenting and explaining such concepts.

• To learn something new--Tikz

Features

Basic Idea:

If we observe various diagrams , the basic elemets which are commonly used are circle and rectangle. To connect them we can use various types of arrows.We can use "->" type of arrow commnly. Also if the aim of diagram is to depict the flow between elements then the way in which they are placed is not critical for consideration. So we can assume that the nodes are placed such that they will form a circle approximately.Considering these things the parameters to be accepted for drawing nodes are decided. Also please note that this diagram is not some domain specific such as theory of computation(automata diagrams),Software engineering(data flow diagrams) but it provides basic framework which can be used as per requirement to draw simple diagrams.

Initial proposal

Initially I proposed to draw diagram with following things:

• Assume there can be only 4 nodes
• The shape of nodes will be circular and after drawing arrows will look like diamond.
• They will be placed in circular fashion
• Colour of node,content of node,label for edge and colour of text will be accepted for each node from user.

Implemented things

The features currently implemented by command are:

• No restriction on number of nodes
• For the shape of nodes there are two choices:circular or rectangular(First parameter of triplet).Default arrows of form "->" are used.
• The nodes will be placed in circular fashion automatically
• Two colours are available for node blue,cyan. Depending on the first parameter that color will be used.
• Content to be writte inside node is accepted as second parameter of triplet
• Text to be written over edge is accepted as third parameter of triplet

Non-Implemented things of initial proposal

The features which were initially proposed and not implemented by command are:

• Accepting color of text inside node

Extra things implemented

The dynamicity in number of nodes and placing them as well of providing option for shape of node as circle and rectangle were added later.

Break up of time

Phase 1:Learning latex,tikz

Basically I was totally new to Tikz and Latex. So it took 10-15 hours to get familiar with it.

Phase 2:Deciding problem statement

There are many many things for which already library is built and available to use.To find what is already implemented and what can be implemented using that took 5-10 hours.

Phase 3:Implementation

For actual implementation it took some time.Initially I drew diagram without accepting any parameters from user. Then I tried to draw it for some hard-coded parameters.It took time to understand command "\newcommand" used to define macros . Defining .sty as per our requirement was easy. Using these my commands are defined.

Implementation

Programming Language:

• Tikz
• Latex

Modules borrowed:

No modules as such are borrowed directly.

Packages used:

Following packages are used:

• tikz
• calc
• ifthen

Libraries used:

Following libraries are used:

• arrows
• positioning
• fit

References:

PGF and TikZ manual for Version 2.0

Implementation details:

• Forloop command:
  This command takes 3 arguements.It first initialises temp to arguement3.Then checks for test condition i.e. arguement2 and if satisfied executes arguement3
• mydia command:
  This command takes two arguements.First arguement gives node details. Second arguement takes number of nodes.This creates nodes dynamically by using \node command and calculating node position dynamically.

For this, commands such as \newcounter,\setcounter,\addtocounter commands.

Difficulties faced:

The difficulties were faced when the number of nodes was not fixed. So to place such arbitrary number of nodes calculations were required.This was done by using polar co-ordinates and setteing angle of polar co-ordinate as 360/No of nodes * node number. The node name is generated automatically as X0,X1,....
This naming is useful while connecting nodes.Also defining \forloop resolved the problem of connecting nodes.

Future Work

1. In future if input can be taken in some format so that any node can be connected to any node(i.e. any number of edges in between two nodes) ,it will be very helpful.
2. Also placement of nodes can be thought so that they can be placed anywhere but according to user input.

Conclusion

So this package can be used to draw simple diagrams depicting flow between entities,actions,objects in various domains such as medical,pure sciences,management,etc and will reduce efforts and save time.

THANK YOU!!!