View source for ASCEND/C2/Iterative-calculations-and-Plotting-Graphs/English

'''Tutorial 6: Iteration & Graph Plotting'''


{| style="border-spacing:0;"
| style="border:0.75pt solid #000001;padding:0.0104in;"| <center>'''Visual Cue'''</center>
| style="border:0.75pt solid #000001;padding:0.0104in;"| <center>'''Narration'''</center>

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide number 1

Title slide
| style="border:0.75pt solid #000001;padding:0.0104in;"| Welcome to the tutorial on '''Iteration & Graph Plotting in ASCEND'''

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Show Slide 2
| style="border:0.75pt solid #000001;padding:0.0104in;"| In this tutorial,

We will learn how to

* Use '''FOR''' loop in '''ASCEND'''
* Use '''Arrays''' in '''MODEL'''
* Plot Graphs



|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide number 3

System Requirement
| style="border:0.75pt solid #000001;padding:0.0104in;"| Here I am using

'''Ubuntu Linux OS v. 12.04'''

'''ASCEND v. 0.9.8'''

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide number 4

Pre-requisites
| style="border:0.75pt solid #000001;padding:0.0104in;"| To follow this tutorial, user must have basic knowledge of '''Linux '''and '''ASCEND'''.


To know more about '''ASCEND,''' please visit '''ascend4.org'''


For relevant tutorials, please visit our website

[http://spoken-tutorial.org/ http://spoken-tutorial.org]

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide number 5

Problem Statement
| style="border:0.75pt solid #000001;padding:0.0104in;"| Suppose we want to study the variation in '''mass''' of a '''thin walled cylindrical vessel''' with respect to its '''H to D ratio.'''

The equations describing our system is:

'''metal mass = metal density * wall vol'''

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Source Code in Text Editor
| style="border:0.75pt solid #000001;padding:0.0104in;"| Let's look at the source code for this problem.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Zoom in on the MODEL vessel and paremeters part of the code.
| style="border:0.75pt solid #000001;padding:0.0104in;"| We have two '''models''' in our file.

The first model defines '''parameters''' that will be passed in the second model.


To know more on writing reusable '''models''' refer to previous lectures in this series.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Zoom out and show the entire MODEL vessel
| style="border:0.75pt solid #000001;padding:0.0104in;"| After defining the parameters, we define the required variables and equations.


Then we write '''METHODs '''to solve them.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Zoom in on the second MODEL vesselplot.
| style="border:0.75pt solid #000001;padding:0.0104in;"| Now we write our second '''MODEL''' '''vesselplot''' to use previously defined '''parameters'''.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight the declaration of n_entries
| style="border:0.75pt solid #000001;padding:0.0104in;"| We define the total number of '''data points''' that we want, by defining '''variable''' '''n_entries'''

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight the declaration of H_to_D_ratio and metal_mass
| style="border:0.75pt solid #000001;padding:0.0104in;"| Therafter, we declare two '''arrays H_to_D_ratio''' and '''metal_mass''' to store the required values.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight the FOR loop
| style="border:0.75pt solid #000001;padding:0.0104in;"| Now,we start a '''FOR''' loop, using which we pass the '''parameters''' of previous model in a new''' array v'''.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight the FOR loop in METHOD values
| style="border:0.75pt solid #000001;padding:0.0104in;"| Note that,we assign values to the previously defined '''array H_to_D_ratio '''under '''METHOD''' values and not in our '''MODEL'''.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Open up ASCEND interface.Load the program and run it.
| style="border:0.75pt solid #000001;padding:0.0104in;"| Before moving any further, let's run our program and see how it stores the values in '''arrays'''.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Point to the type 'array' displayed on interface
| style="border:0.75pt solid #000001;padding:0.0104in;"| As you can see, '''ASCEND''' clearly indicates that '''H_to_D_ratio, metal_mass '''and '''v''' are '''arrays'''.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Click on 'H_to_D_ratio' arrow
| style="border:0.75pt solid #000001;padding:0.0104in;"| To see different values stored in the '''array''', we just click on the drop down menu.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Click on 'v' arrow
| style="border:0.75pt solid #000001;padding:0.0104in;"| Also, to see the values of the parameters passed to '''array v''', we click on the arrow next to it.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Source code in Text editor
| style="border:0.75pt solid #000001;padding:0.0104in;"| Now, let's learn how to plot a graph between the values stored in the two '''arrays.'''

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight REQUIRE "plot.a4l”
| style="border:0.75pt solid #000001;padding:0.0104in;"| Firstly, we need to include '''plot.a4l''' '''library''' in our '''model''' to use the '''plot function.'''

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight massVSratio IS_A plt_plot_symbol
| style="border:0.75pt solid #000001;padding:0.0104in;"| To plot a graph in '''ASCEND''', we need to declare a '''variable''' of the type''' plt_plot_symbol'''.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight (CurveSet, Curves)
| style="border:0.75pt solid #000001;padding:0.0104in;"| This declaration requires two '''parameters''' namely '''Curveset''' and '''Curves'''.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight the following lines:

CurveSet IS_A set OF symbol_constant;

<nowiki>CurveSet :== ['test'];</nowiki>
| style="border:0.75pt solid #000001;padding:0.0104in;"| '''Curveset '''allows us to tag and identify each of the curves we plot.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight the following lines:

<nowiki>Curves['test'] IS_A plt_curve([1..n_entries], metal_mass,H_to_D_ratio)</nowiki>
| style="border:0.75pt solid #000001;padding:0.0104in;"| The second parameter '''Curves''' requires 3 '''parameters-'''

# a set of '''integers''' and
# two lists of data giving the '''y-values''' and the '''x-values''' for the curve.

In our case, this set of '''integers''' is from 1to 20.


And the '''two arrays''' – '''metal_mass '''& '''H_to_D_ratio''' gives the '''y''' and '''x values''' respectiveley.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Highlight the following lines:

massVSratio.title :='Metal mass of the walls vs H to D ratio for a thin-walled cylindrical vessel';

massVSratio.XLabel := 'H to D ratio';

massVSratio.YLabel := 'metal mass IN kg/m^3
| style="border:0.75pt solid #000001;padding:0.0104in;"| We give title and label for our plot under the '''METHODS''' section.

|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Open up ASCEND interface.Load the program and run it.
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Let us now see how to get the required plot.




|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Right-click on massVSratio and choose the plot option
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| We simply need to click on the '''mass vs ratio''' and choose the '''plot''' option.

|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Maximise the plot window
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| This gives us the required plot, with the title and the labels that we mentioned in the code.

|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Source code in Text editor
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Let us now see what happens if we don't mention the '''plot title'''.

|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Remove the massVSratio.tittle line from the source code and save it.
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| We remove the '''title line''' from our source code.

|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Open up ASCEND interface.Load the program and run it.
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| We will re-compile the program.

|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Maximise the plot window
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| We can clearly see that '''ASCEND''' titles the plot as ''''undefined''''.

|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Slide number 6

Summary
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| This brings us to the end of this tutorial. Let’s summarize.

|-
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| Click to bring up the bullets
| style="border-top:none;border-bottom:0.75pt solid #000001;border-left:0.75pt solid #000001;border-right:0.75pt solid #000001;padding:0.0104in;"| In this tutorial, we have learnt to

* Use '''FOR''' loop in '''ASCEND'''
* Use '''Arrays''' in '''MODEL'''
* Plot Graphs
* using a sample program



|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide Number 7

Assignment
| style="border:0.75pt solid #000001;padding:0.0104in;"| As an assignment, change the size of array to 40 and re-attempt this problem.

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide Number 8

About slide
| style="border:0.75pt solid #000001;padding:0.0104in;"| Watch the video available at

[http://spoken-tutorial.org/What_is_a_Spoken_Tutorial http][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial ://][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial spoken][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial -][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial tutorial][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial .][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial org][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial /][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial What][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial _][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial is][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial _][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial a][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial _][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial Spoken][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial _][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial Tutorial]

It summarises the Spoken Tutorial project

If you do not have good bandwidth, you can download and watch it

|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide number 9

About slide
| style="border:0.75pt solid #000001;padding:0.0104in;"| The Spoken Tutorial Project Team:

Conducts workshops using spoken tutorials

Gives certificates to those who pass an online test

For more details, please write to

contact@spoken-tutorial.org




|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide number 10

Acknowledgment
| style="border:0.75pt solid #000001;padding:0.0104in;"| Spoken Tutorial Project is a part of the Talk to a Teacher project

It is supported by the National Mission on Education through ICT, MHRD, Government of India

More information on this Mission is available at[http://spoken-tutorial.org/NMEICT-Intro  ][http://spoken-tutorial.org/NMEICT-Intro http][http://spoken-tutorial.org/NMEICT-Intro ://][http://spoken-tutorial.org/NMEICT-Intro spoken][http://spoken-tutorial.org/NMEICT-Intro -][http://spoken-tutorial.org/NMEICT-Intro tutorial][http://spoken-tutorial.org/NMEICT-Intro .][http://spoken-tutorial.org/NMEICT-Intro org][http://spoken-tutorial.org/NMEICT-Intro /][http://spoken-tutorial.org/NMEICT-Intro NMEICT][http://spoken-tutorial.org/NMEICT-Intro -][http://spoken-tutorial.org/NMEICT-Intro Intro]




|-
| style="border:0.75pt solid #000001;padding:0.0104in;"| Slide number 11

Thank you slide
| style="border:0.75pt solid #000001;padding:0.0104in;"| This is Tarun Gangwar from IIT Bombay signing off. Thank you for joining.

|}