Difference between revisions of "Gnuplot/C2/Multiple-plots-in-a-canvas/English"
Line 21: | Line 21: | ||
'''Learning Objectives''' | '''Learning Objectives''' | ||
|| * Add a rectangle object in the background | || * Add a rectangle object in the background | ||
− | * Generate output on the screen | + | * Generate output on the screen |
* Save the output to '''svg''' file | * Save the output to '''svg''' file | ||
Line 30: | Line 30: | ||
* '''Ubuntu Linux''' 16.04 OS | * '''Ubuntu Linux''' 16.04 OS | ||
− | * '''Gedit''' version 3.18 | + | * '''Gedit''' version 3.18 |
* '''gnuplot''' version 5.2.6 | * '''gnuplot''' version 5.2.6 | ||
Line 38: | Line 38: | ||
[https://spoken-tutorial.org/ https:spoken-tutorial.org] | [https://spoken-tutorial.org/ https:spoken-tutorial.org] | ||
|| To follow this tutorial, | || To follow this tutorial, | ||
− | * Learner must be familiar with | + | * Learner must be familiar with the basics of gnuplot. |
* For pre-requisite tutorials, please visit this site. | * For pre-requisite tutorials, please visit this site. | ||
Line 55: | Line 55: | ||
|- | |- | ||
− | || Type '''gedit & | + | || Type '''gedit &'''. |
− | || Type '''gedit space ampersand | + | || Type '''gedit space ampersand'''. |
The '''ampersand''' makes the process run in the background. | The '''ampersand''' makes the process run in the background. | ||
It detaches the process from the '''terminal'''. | It detaches the process from the '''terminal'''. | ||
|- | |- | ||
− | || | + | || Press '''Enter'''. |
− | || '''Windows''' users may use '''notepad''' or '''wordpad'''. | + | || Press '''Enter''' to open '''gedit'''. |
+ | '''Windows''' users may use '''notepad''' or '''wordpad'''. | ||
We will write the required commands in a text file. | We will write the required commands in a text file. | ||
|- | |- | ||
− | || Type, '''# my first multiplot''' and press '''Enter'''. | + | || Type, '''#my first multiplot''' and press '''Enter'''. |
|| I will type '''hash my first multiplot''' and press '''Enter''' . | || I will type '''hash my first multiplot''' and press '''Enter''' . | ||
This is a comment line. | This is a comment line. | ||
Line 77: | Line 78: | ||
|- | |- | ||
|| Cursor on '''gedit''' window. | || Cursor on '''gedit''' window. | ||
− | || We will plot, '''sin x, cos x''', a '''straight line''' and an '''exponential decay''' | + | || We will plot, '''sin x, cos x''', a '''straight line''' and an '''exponential decay''' graphs. |
|- | |- | ||
Line 89: | Line 90: | ||
'''set origin 0,0''' | '''set origin 0,0''' | ||
'''set size 0.5, 0.5''' | '''set size 0.5, 0.5''' | ||
− | || Enter the next two commands define the size and placement for the '''sin x''' plot. | + | || Enter the next two commands as shown here. |
+ | They define the size and placement for the '''sin x''' plot. | ||
|- | |- | ||
Line 105: | Line 107: | ||
'''set xrange[-10:10] yrange[-2:2]''' | '''set xrange[-10:10] yrange[-2:2]''' | ||
'''set title '”x-sin(x) plot”''' | '''set title '”x-sin(x) plot”''' | ||
− | + | ||
− | || | + | || We will set x and y range, and title for the '''sin (x)''' plot. |
− | These are the graph formatting details for the plot '''sin x'''. | + | These are the graph formatting details for the '''sin x''' plot. |
+ | |||
+ | |- | ||
+ | || Type '''plot sin(x) ''' and press '''Enter'''. | ||
+ | || We will then issue the plot command for sin(x). | ||
|- | |- | ||
|| Type, | || Type, | ||
'''# cos (x) - x plot''' | '''# cos (x) - x plot''' | ||
− | || | + | || I will enter details for the second plot, which is '''cos (x)'''. |
First, write a comment line, to indicate it is the part for cos (x), in the script. | First, write a comment line, to indicate it is the part for cos (x), in the script. | ||
Type '''hash cos x - x''' plot. | Type '''hash cos x - x''' plot. | ||
Line 124: | Line 130: | ||
'''set title "x-cos(x) graph" ''' | '''set title "x-cos(x) graph" ''' | ||
'''plot cos(x) notitle ''' | '''plot cos(x) notitle ''' | ||
− | || Enter the commands as | + | || Enter the commands as shown here. |
+ | Pause the video as and when necessary. | ||
|- | |- | ||
Line 144: | Line 151: | ||
|| Type | || Type | ||
'''#straight line plot''' | '''#straight line plot''' | ||
− | || Now, I will enter details for the third plot. | + | || Now, I will enter the details for the third plot. |
− | Write a comment, starting with a hash | + | Write a comment, starting with a hash. |
Type, '''straight line plot''' and press '''Enter'''. | Type, '''straight line plot''' and press '''Enter'''. | ||
Line 155: | Line 162: | ||
'''set size 0.5, 0.5 ''' | '''set size 0.5, 0.5 ''' | ||
|| Again specify the size and position for this graph. | || Again specify the size and position for this graph. | ||
+ | The position places the graph in the top right corner. | ||
− | |||
− | |||
|- | |- | ||
|| Type the lines, | || Type the lines, | ||
Line 165: | Line 171: | ||
'''plot 'data.txt' using 1:3 with linespoint notitle ''' | '''plot 'data.txt' using 1:3 with linespoint notitle ''' | ||
and press '''Enter'''. | and press '''Enter'''. | ||
− | || Enter the commands as | + | || Enter the commands as shown here. |
Specify the title and autoscale axis range and issue the plot command. | Specify the title and autoscale axis range and issue the plot command. | ||
Line 188: | Line 194: | ||
|- | |- | ||
|| Cursor in '''gedit''' window. | || Cursor in '''gedit''' window. | ||
− | || | + | || Let's write the part of '''script''' to generate the exponential decay plot. |
|- | |- | ||
Line 199: | Line 205: | ||
'''set origin 0.0,0.5 ''' | '''set origin 0.0,0.5 ''' | ||
and press '''Enter'''. | and press '''Enter'''. | ||
− | || For this plot, set the position above the '''sin x''' in the top left corner. | + | || For this plot, set the position above the '''sin x''' plot in the top left corner. |
|- | |- | ||
Line 208: | Line 214: | ||
'''plot 'data.txt' using 1:2 with linespoint notitle ''' | '''plot 'data.txt' using 1:2 with linespoint notitle ''' | ||
and press '''Enter'''. | and press '''Enter'''. | ||
− | || Set size, title for graph and autoscale data. | + | || Set size, title for graph and autoscale the data. |
Read in the columns for '''x''' and '''y''' data from the data file in the '''plot''' command. | Read in the columns for '''x''' and '''y''' data from the data file in the '''plot''' command. | ||
+ | Here, it is column 1 and column 2 for '''x''' and '''y''' data. | ||
|- | |- | ||
Line 229: | Line 236: | ||
|- | |- | ||
|| Minimize '''gedit'''. | || Minimize '''gedit'''. | ||
− | || | + | || Minimize the '''gedit''' window. |
|- | |- | ||
− | || Go to | + | || Go to the '''terminal'''. |
− | || Go to the '''terminal''' | + | || Go to the '''terminal'''. |
|- | |- | ||
Line 253: | Line 260: | ||
|- | |- | ||
|| Show the graphics window with 4 plots. | || Show the graphics window with 4 plots. | ||
− | || A graphic window with four graphs | + | || A graphic window with four graphs appear in the canvas. |
|- | |- | ||
|| Show '''multiplot mode terminal prompt''' video patch from another '''terminal'''. | || Show '''multiplot mode terminal prompt''' video patch from another '''terminal'''. | ||
− | |||
|| In case of errors in the script, '''gnuplot''' will remain in the '''multiplot''' mode. | || In case of errors in the script, '''gnuplot''' will remain in the '''multiplot''' mode. | ||
Line 267: | Line 273: | ||
|- | |- | ||
|| Cursor on the '''terminal'''. | || Cursor on the '''terminal'''. | ||
− | || To '''reset''' | + | || To '''reset''' default setting, the '''unset''' command is used. |
If we do not '''unset''' the format, the set format will not '''reset''' to default setting. | If we do not '''unset''' the format, the set format will not '''reset''' to default setting. | ||
Line 301: | Line 307: | ||
'''set object 1 rectangle from graph 0,0 to graph 1,1 behind fillcolor rgb 'cyan' fillstyle solid noborder''' | '''set object 1 rectangle from graph 0,0 to graph 1,1 behind fillcolor rgb 'cyan' fillstyle solid noborder''' | ||
and press '''Enter'''. | and press '''Enter'''. | ||
− | || To change background color, we will insert an object, in the graph. | + | || To change the background color, we will insert an object, in the graph. |
Enter the command as seen on the screen. | Enter the command as seen on the screen. | ||
Line 320: | Line 326: | ||
'''set ytics 40000''' | '''set ytics 40000''' | ||
and press '''Enter'''. | and press '''Enter'''. | ||
− | || | + | || For the straight line plot, add modifications on axis formats. |
+ | The y axis numbers are large. | ||
The commands are added before the '''plot''' command as shown. | The commands are added before the '''plot''' command as shown. | ||
Revision as of 15:09, 3 January 2020
Visual Cue | Narration |
Slide Number 1
Title Slide Multiple plots in a canvas |
Welcome to the tutorial on Multiple plots in a canvas. |
Slide Number 2
Learning Objectives |
In this tutorial we will learn to,
|
Slide Number 3
Learning Objectives |
* Add a rectangle object in the background
|
Slide Number 4
Pre-requisites |
To record this tutorial, I am using,
|
Slide Number 5
System and Software Requirement https:spoken-tutorial.org |
To follow this tutorial,
|
Slide Number 5
Code files |
|
Press Ctrl+Alt+T.
Enter the command cd Desktop. |
Open a terminal and change the directory to Desktop.
I will demonstrate the multiplot command, with four graphs in one canvas. |
Type gedit &. | Type gedit space ampersand.
The ampersand makes the process run in the background. It detaches the process from the terminal. |
Press Enter. | Press Enter to open gedit.
Windows users may use notepad or wordpad. We will write the required commands in a text file. |
Type, #my first multiplot and press Enter. | I will type hash my first multiplot and press Enter .
This is a comment line. |
Type set multiplot, press Enter. | Next, set the environment to multiplot mode, as set space multiplot.
Start a new line and leave a blank line for clarity. |
Cursor on gedit window. | We will plot, sin x, cos x, a straight line and an exponential decay graphs. |
Type header line,
#x-sin(x) plot |
I will start with the script for the sin(x) part.
In the next line, enter a comment to identify that, the plot is for sin x. |
Type lines,
set origin 0,0 set size 0.5, 0.5 |
Enter the next two commands as shown here.
They define the size and placement for the sin x plot. |
Hover mouse next to set origin 0,0 . | This plot is set at position zero, zero which is the origin.
This is the left hand bottom corner of the page. |
Hover mouse next to set size 0.5,0.5 . | Here I am specifying plot size to be a square of point 5 by point 5.
This size is relative to the total page size and makes it a quarter of the page. |
Type the following lines,
set xrange[-10:10] yrange[-2:2] set title '”x-sin(x) plot” |
We will set x and y range, and title for the sin (x) plot.
These are the graph formatting details for the sin x plot. |
Type plot sin(x) and press Enter. | We will then issue the plot command for sin(x). |
Type,
# cos (x) - x plot |
I will enter details for the second plot, which is cos (x).
First, write a comment line, to indicate it is the part for cos (x), in the script. Type hash cos x - x plot. |
Type the lines,
set origin 0.5,0.0 set size 0.5, 0.5 set xrange[-10:10] set yrange[-2:2] set title "x-cos(x) graph" plot cos(x) notitle |
Enter the commands as shown here.
Pause the video as and when necessary. |
Hover mouse next to set origin and set size. | Here, I specify the position and size of the second plot.
The position is set to the right side of the sin x plot. |
Show the data.txt file icon in Desktop. | I will use the data from the text file data.txt, for the third and fourth plots.
This file is provided to you in the Code files link of this tutorial. I have downloaded and saved the file on Desktop. |
Show screenshot of the file. | The file has 3 data columns, x , y1 and y2 . |
Type
#straight line plot |
Now, I will enter the details for the third plot.
Write a comment, starting with a hash. Type, straight line plot and press Enter. |
Type the lines,
set origin 0.5,0.5 set size 0.5, 0.5 |
Again specify the size and position for this graph.
The position places the graph in the top right corner. |
Type the lines,
set title "straight line" set xrange[*:*] set yrange[*:*] plot 'data.txt' using 1:3 with linespoint notitle and press Enter. |
Enter the commands as shown here.
Specify the title and autoscale axis range and issue the plot command. |
Hover mouse over 1:3 in the plot command. | The 3rd column in the data file is the y data values for the straight line plot. |
Cursor in gedit window. | Pause the video when required to enter the commands. |
Hover mouse over origin, xrange and yrange. | The stars specify autoscale for axes range. |
Hover mouse next to 1:3 .
Hover mouse next to notitle. |
Here I am using column 1 for x data and column 3 for y data.
Here I also specify, no legend title is required in the plot. |
Cursor in gedit window. | Let's write the part of script to generate the exponential decay plot. |
Type, #Exponential decay and
press Enter. |
I will type hash exponential decay for the comment line. |
Type,
set origin 0.0,0.5 and press Enter. |
For this plot, set the position above the sin x plot in the top left corner. |
Type,
set size 0.5, 0.5 set title "Exponential decay" set autoscale plot 'data.txt' using 1:2 with linespoint notitle and press Enter. |
Set size, title for graph and autoscale the data.
Read in the columns for x and y data from the data file in the plot command. Here, it is column 1 and column 2 for x and y data. |
Press Enter.
Type unset multiplot and press Enter. |
I will leave an blank line after this.
Finally, unset the multiplot mode with the command, unset space multiplot. |
Press ctrl+S. | Press ctrl S to open the file save as dialogue box. |
Type filename as, multiplot.dem
Click on save. |
Save the file in Desktop directory with filename multiplot.dem.
Click on save to save the script. |
Minimize gedit. | Minimize the gedit window. |
Go to the terminal. | Go to the terminal. |
Type gnuplot and press Enter. | Let’s open gnuplot . |
Press Ctrl+L . | I will also clear the screen. |
Cursor in the terminal. | Let's run the script to generate the multiplot. |
Type load 'multiplot.dem' and press Enter. | Enter the command, load space in single quotes, multiplot.dem. |
Show the graphics window with 4 plots. | A graphic window with four graphs appear in the canvas. |
Show multiplot mode terminal prompt video patch from another terminal. | In case of errors in the script, gnuplot will remain in the multiplot mode. |
Type unset space multiplot and press Enter. | Then the graphics plot is also not generated.
If so, type unset space multiplot. |
Cursor on the terminal. | To reset default setting, the unset command is used.
If we do not unset the format, the set format will not reset to default setting.
|
Hover mouse next to gnuplot prompt. | This returns the terminal to gnuplot prompt.
If Debug the script to make it error free and run the script to generate the plot. |
Go to the graphics window. | A few formatting modifications could improve the look of the graphs. |
Close the graphics window. | Hence, I will make the following modifications in the script. next.
Close the graphics window. |
Go back to gedit script. | Go back to the gedit window to edit the script.
If you had closed it, please open the script file to edit it further. |
Scroll to the sin(x) script part.
Start a new line before plot command. |
Scroll to the sin x part of the script.
Let's change the background color of the sin x plot. Start a new line before the plot command. |
Type
set object 1 rectangle from graph 0,0 to graph 1,1 behind fillcolor rgb 'cyan' fillstyle solid noborder and press Enter. |
To change the background color, we will insert an object, in the graph.
Enter the command as seen on the screen. |
Hover mouse next to object, cyan and noborder. | Here, we set a cyan colored rectangle, without border, for background. |
Start a new line after the plot command.
Type, unset object 1 and press Enter. |
Start a new line after the plot command.
Unset the cyan background object, as shown here. |
Type in the three lines above the plot command line,
set format y "10^{%L}" set xtics rotate set ytics 40000 and press Enter. |
For the straight line plot, add modifications on axis formats.
The y axis numbers are large. The commands are added before the plot command as shown. |
Point mouse to set format y, then to xtics rotate and then ytics 40000. | The y axis numbers are large.
So I will change the notation. I will also rotate the x axis tics in the plot label. I also specify the y tics spacing. |
Type unset format y . | We will unset the y axis format after the plot command is executed. |
Scroll down the script file. | Next go to the part of exponential decay script . |
Before the plot command, type in the three lines,
set format y "10^{%L}" set xtics rotate set ytics 40000 and press Enter. |
I will add the same formatting commands, as in the straight line plot.
Notice that, they are added before the plot command. |
Type, unset format y after the plot command. | Start a new line after plot command and unset the format of y-axis. |
Scroll to top of the script. | Let's add command to print the graph into an image file.
Scroll up to the top of the script file. |
Before the set multiplot line, type,
set terminal svg size 800,800 enhanced font 'Verdana,12' |
Type set term to svg as seen before starting the multiplot mode. |
Type
set output 'multiplot.svg' and press Enter. |
Direct the output to a svg file as seen.
These are done before the multiplot command is executed. |
Scroll to the bottom of the script. | Scroll to the bottom of script file and unset the output.
This is done after before we unset the multiplot mode. |
Type unset output and press Enter. | Enter the command unset space output. |
Press Ctrl+S and minimize gedit. | Press Ctrl-S to save the file and minimize gedit. |
Go to the terminal. | Go back to the terminal from where gnuplot was opened.
If you had closed gnuplot, please open gnuplot again. |
Enter the command load 'multiplot.dem' . | Run the updated multiplot.dem script.
Now, the graphics window does not open, since the output is a svg file, . |
Enter the command quit. | Enter the command quit, to quit gnuplot. |
Go to Desktop. | Go to Desktop . |
Open multiplot.svg file. | Open the file, multiplot.svg that is created on the Desktop.
Since the path is Desktop the output file is generated in the Desktop directory. |
Cursor on the svg file. | You may add commands to the script file to generate the desired output. |
Close the image file. | Similar scripts are available in the gnuplot demo website.
Practice and familiarize with the commands and styles. I will close the image file. |
Slide Number 6
Summary |
Now, to summarize, in this tutorial, we * Learned the multiplot command
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Slide Number 7
Assignment 1 |
For assignment activity, please do the following.
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Slide Number 8
Assignment 2 |
With the data.txt, provided, do the following.* Generate one plot covering the canvas with x-y1 data points.
|
Show assignment result screenshot. | Completed assignment looks similar to this. |
Slide Number 9
Spoken Tutorial Project |
This video summarises the Spoken Tutorial Project .
Please download and watch it. |
Slide Number 10
Spoken Tutorial workshops |
We conduct workshops and give certificates.
For more details, please write to us. |
Slide Number 11
Forum for specific questions: |
Post your timed queries in the forum. |
Slide Number 12
Acknowledgement |
Spoken Tutorial Project is funded by MHRD, Government of India. |
This is Rani from IIT, Bombay.
Thank you for joining. |