Gnuplot/C2/Plotting-datasets-from-file/English

Title of script: Plotting datasets from file

Author: Rani Parvathy

Keywords: gnuplot, video tutorial, spoken tutorial, plot data from file, plot more than one graph, change line color, set key, set symbol size, month, year, date formatting

Visual Cue	Narration
Slide Number 1 Title Slide Plotting datasets from file	Welcome to the tutorial on Plotting datasets from a file
Slide Number 2 Learning Objectives	In this tutorial we will learn to, Plot x-y graph from a dataset in a file Add two plots in a graph Write legend and set time stamp Change line color Set symbol style and size Change axis format and label style
Slide Number 3 System and Software Requirement	To record this tutorial, I am using Debian Linux Gedit 3.22.0 and have gnuplot 5.2.5 installed
Slide Number 4 Samson Microphone	To record audio, Samson USB portable microphone was used. The model number SAGOMIC I bought it from amazon website, for about rupees four thousand It may be available in other websites.
Slide Number 5 Pre-requisites	To follow this tutorial, learner's must be familiar with, Basic computer and internet skills Have concept of graphing and Have high school level Mathematics skills
Slide Number 6 Pre-requisites	Please locate this tutorial on our web page, spoken hyphen tutorial dot org Pre-requisite spoken tutorials, if any, will be mentioned in this page
Go to Desktop	Go to desktop We will plot a graph from data in a text file data dot txt The file is provided with this tutorial.
Show data.txt icon in Desktop directory.	It is saved in the Desktop folder for me.
Double click on the icon	Double click on the file icon to open and view the file. File opens in gedit text editor for me
	Data has three columns. The first row consists of headers and starts with a hash
	First column contain x data. 2nd and 3rd columns are two sets of y data.
Click on x sign	Close the file by File > quit or click on the 'x' sign
Press ctrl+alt+t	Press control alt t, keys together on keyboard, to open a terminal
	A terminal opens.
cd Desktop	Change directory to Desktop directory as seen on the screen.
	Depending on your operating system, please set the terminal
set term qt	I will type set space term space qt. This works for most operating systems
gnuplot	Type gnuplot in command prompt and press enter, to open gnuplot I will Press control L to bring terminal prompt to top of screen, for clarity.
Hight on screen, >plot "data.txt" using 1:2 title 'Y1'	First let's make a plot from x and y1 data columns. Enter command as seen on the screen
replot	Replot to see the graph Here we also added legend in the same command line A graphic window opens Next, let's make symbol size larger
Type set pointsize 1.5 Press enter	To set symbol point size, type set pointsize 1.5 Press enter
replot	Replot to see the updated graph You may pause the video and explore symbol size and choose a size of your choice
	Now, Say I want to compare both y1 and y2 data on x-axis
Highlight >plot "data.txt" using 1:2 title 'Y1' , "data.txt" using 1:3 title 'Y2'	For this purpose, use the plot command as above, in series, separated by a comma The command is shown on the screen.
	Let's set y-axis to logarithmic scale from linear next
>set logscale y replot	Use command set space logscale space y to set logscale. Replot to see the result.
	The exponential curve change to linear line due to the logarithmic scale
>unset logscale y	To go back to linear scale for y-axis, use command, unset space logscale space y
>replot	Please replot to see the resulting change.
plot "data.txt" using 1:3 with linespoints	Say, I desire to draw a line between data points for x and y2 data set. I will use the command as seen on the screen.
	Add with lines points in the plot command itself.
	Next, let's change graph properties. Say, I want a larger size filled circle data points and color them blue.
Highlight on screen >plot "data.txt" using 1:3 title 'Y2' with linespoint lc 'blue' lt 1 lw 2 pt 7 ps 1.5	Enter the command, as seen on the screen. This changes color, point style and style line.
Hover mouse next to lc	Here, lc sets line color to blue. We can also use hexadecimal code for a chosen color.
Hover mouse over lw	Lw 2 sets line width to two
Hover mouse next to pt	Pt sets point type or symbol style to 7, which is a filled circle.
Hover mouse next ps	Ps sets point size or symbol size to 1.5
	We may wish to change the format for axis labels on many occasions.
Hover mouse on y-axis range	Here, the y-axis numbers are large.
	We may want to use scientific notation.
	I will use set format command for this purpose.
>Set format y	Type set space format, followed by axis name. Here it is y.
'%0.2e'	Follow it by percent sign 2 e within single quotes as in the video.
	You may also use the following syntax for changing format and range.
>set yrange [1:1.5e5] ctrl -L	Use set space yrange space 1 colon 1 point 5e5 in square braces This also changes format of y axis I will press control l to bring terminal prompt to top of the screen for clarity.
set border linewidth 2 lc 'red'	We can also change color of the border and line width. The commands are shown on the screen.
	We may also want to have a time stamp with the graph.
>set timestamp	Type set space timestamp to add time stamp
	Notice time stamp for the plot is displayed on bottom of the plot
Slide Number 7 Summary	To summarize, in this tutorial, we Plotted data from a file Added two plots in a graph Wrote legend title Changed line color
Slide Number 8 Summary	* Learned to change symbol style and size Formatted axis type and label style Changed border line color and Learned to set time stamp
Slide Number 9 Summary	For assignment activity, please do the following, Explore numbers 0-10 for color choice for line Explore symbol styles for number choice 0-9
Slide Number 10 Spoken Tutorial Project	This video summarizes the Spoken Tutorial Project If you do not have good bandwidth, you may download and watch it.
Slide Number 11 Spoken Tutorial workshops	We conduct workshops using spoken tutorials and give certificates. Please write to us.
Slide Number 12 Forum for specific questions: *	Post your timed queries in the forum.
Slide Number 13 Acknowledgement	Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.
	Thank you for joining.

Contributors and Content Editors

Madhurig, Ranipv076, Snehalathak