Product Perfect

Gnuplot is an open-source, command-line driven graphing utility for Linux, OS/2, MS Windows, OSX, VMS and many other platforms. It was originally created to allow scientists and students to visualize mathematical functions and data interactively. Gnuplot supports many types of plots in either 2D or 3D. It can draw using lines, points, boxes, contours, vector fields, surfaces and various associated text. It also supports various specialized plot types including histograms and pie charts. Gnuplot is able to output directly to the terminal or save in a variety of graphics file formats such as SVG, JPEG and PNG.

Ask the right questions secure the right Gnuplot talent among an increasingly shrinking pool of talent.

First 20 minutes

General Gnuplot app knowledge and experience

The first 20 minutes of the interview should seek to understand the candidate's general background in Gnuplot application development, including their experience with various programming languages, databases, and their approach to designing scalable and maintainable systems.

How would you install Gnuplot on a Linux-based system?

You can install Gnuplot on a Linux-based system using the package manager. For example, on a Ubuntu system, you would use the command 'sudo apt-get install gnuplot'.

What are the basic components of a Gnuplot script?

A basic Gnuplot script consists of a set of commands that define the data to be plotted, the type of plot, the axes, labels, and other elements of the plot.

How would you plot a simple function in Gnuplot?

You can plot a simple function in Gnuplot using the 'plot' command. For example, to plot the function y = x^2, you would use the command 'plot x**2'.

What is the purpose of the 'set' command in Gnuplot?

The 'set' command in Gnuplot is used to configure various options for the plot, such as the title, labels, range of the axes, and the style of the plot.

How would you save a Gnuplot plot to a file?

You can save a Gnuplot plot to a file using the 'set output' command to specify the filename and the 'set terminal' command to specify the file format. For example, 'set terminal png; set output 'plot.png'; plot x**2'.

The hiring guide has been successfully sent to your email address.

Oops! Something went wrong while submitting the form.

What you’re looking for early on

Does the candidate have a strong understanding of Gnuplot?

Has the candidate demonstrated problem-solving skills?

Is the candidate able to communicate effectively?

Does the candidate have experience with other relevant technologies?

Next 20 minutes

Specific Gnuplot development questions

The next 20 minutes of the interview should focus on the candidate's expertise with specific backend frameworks, their understanding of RESTful APIs, and their experience in handling data storage and retrieval efficiently.

How would you plot data from a file in Gnuplot?

You can plot data from a file in Gnuplot using the 'plot' command with the filename as an argument. For example, 'plot 'data.txt' using 1:2' would plot the data in the file 'data.txt', using the first column as the x values and the second column as the y values.

What is the purpose of the 'using' keyword in Gnuplot?

The 'using' keyword in Gnuplot is used to specify which columns of the data file to use for the x and y values when plotting data from a file.

How would you create a multiplot in Gnuplot?

You can create a multiplot in Gnuplot using the 'set multiplot' command, followed by multiple 'plot' commands for each plot. You can use the 'set size' and 'set origin' commands to control the size and position of each plot.

Describe the difference between the 'plot' and 'splot' commands in Gnuplot.

The 'plot' command in Gnuplot is used for creating 2D plots, while the 'splot' command is used for creating 3D plots.

What are the different types of terminals in Gnuplot?

Gnuplot supports a variety of terminals for different output formats. These include 'png', 'jpeg', 'pdf', 'svg', 'eps', and 'gif' for image formats, 'dumb' for ASCII art, 'x11', 'windows', and 'aqua' for interactive display on different operating systems, and 'latex', 'epslatex', 'pdflatex', and 'pslatex' for LaTeX output.

The hiring guide has been successfully sent to your email address.

Oops! Something went wrong while submitting the form.

At this point, a skilled Gnuplot engineer should demonstrate strong problem-solving abilities, proficiency in Gnuplot programming language, and knowledge of software development methodologies. Red flags include lack of hands-on experience, inability to articulate complex concepts, or unfamiliarity with standard coding practices.

Digging deeper

Code questions

These will help you see the candidate's real-world development capabilities with Gnuplot.

What does the following simple Gnuplot script do?
set terminal png
set output 'plot.png'
plot 'datafile.dat' with lines
This script sets the output format to PNG, specifies the output file name as 'plot.png', and plots the data from 'datafile.dat' using lines to connect the data points.
What does the following Gnuplot script do?
set xrange [0:10]
set yrange [0:100]
plot x**2
This script sets the range for the x-axis from 0 to 10 and the range for the y-axis from 0 to 100. It then plots the function y = x^2.
What does the following Gnuplot script do?
array A[5] = [1,2,3,4,5]
plot A using 1:2 with linespoints
This script creates an array A with 5 elements. It then plots the array using the first column as the x-axis and the second column as the y-axis, connecting the data points with lines and points.
What does the following Gnuplot script do?
set terminal pngcairo size 800,600 enhanced font 'Verdana,10'
set output 'output.png'
plot sin(x)
This script sets the output format to PNG using the Cairo library, sets the size of the output image to 800x600 pixels, enhances the image quality, and sets the font to Verdana with a size of 10. It then specifies the output file name as 'output.png' and plots the sine function.

Wrap-up questions

Final candidate for Gnuplot Developer role questions

The final few questions should evaluate the candidate's teamwork, communication, and problem-solving skills. Additionally, assess their knowledge of microservices architecture, serverless computing, and how they handle Gnuplot application deployments. Inquire about their experience in handling system failures and their approach to debugging and troubleshooting.

How would you create a histogram in Gnuplot?

You can create a histogram in Gnuplot by setting the style to 'histogram' using the 'set style data histogram' command, and then using the 'plot' command to plot the data.

What is the purpose of the 'fit' command in Gnuplot?

The 'fit' command in Gnuplot is used to fit a function to the data points in a plot. This can be used for regression analysis and curve fitting.

How would you add error bars to a plot in Gnuplot?

You can add error bars to a plot in Gnuplot by specifying the 'yerrorbars' or 'xerrorbars' option in the 'plot' command, and providing an additional column of data in the data file for the error values.

Gnuplot application related

Product Perfect's Gnuplot development capabilities

Beyond hiring for your Gnuplot engineering team, you may be in the market for additional help. Product Perfect provides seasoned expertise in Gnuplot projects, and can engage in multiple capacities.

Gnuplot Consultive assessments

Gnuplot Application Conversion Assessment Gnuplot Application Integration Assessment Gnuplot Data & Database Integration Assessment

Custom Gnuplot development projects

Custom Gnuplot App Conversion Gnuplot Custom App Development Process App UI Design for Gnuplot Facelifts

Hiring guide for Gnuplot Engineers

Gnuplot Developer Hiring Guide

What you’re looking for early on

The ideal back-end app developer

What you’re looking to see on the Gnuplot engineer at this point.

Gnuplot Consultive assessments

Custom Gnuplot development projects