How to Suppress the WARNING: Plotting with an 'unknown' terminal in Gnuplot

Discover a simple way to disable the annoying warning in Gnuplot when using an 'unknown' terminal. Here's how to use the `stats` command effectively!
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How to Suppress the WARNING: Plotting with an 'unknown' terminal in Gnuplot

If you're using Gnuplot for data analysis and visualization, you may have encountered the warning that reads: "WARNING: Plotting with an 'unknown' terminal." This warning can be quite annoying, especially when you are running a script that only aims to compute dimensions or other statistical properties of your data without actually plotting anything.

In this guide, we will explore why you receive this warning and how to effectively suppress it.

Understanding the Issue

The core problem arises when you set the terminal to unknown, which is valid if you want Gnuplot to operate without displaying any graphics. However, Gnuplot doesn't recognize unknown as a plotting terminal, leading to that frustrating warning every time you run your script.

Your script might look something like this:

[[See Video to Reveal this Text or Code Snippet]]

While this setup is functional for computing values, it produces the warning because Gnuplot is expecting a valid terminal for plotting.

A Practical Solution: Using the stats Command

Fortunately, starting from Gnuplot version 4.6.0, there's a way to compute statistical values without the need to suppress plotting feedback through terminal settings. Instead of setting the terminal to unknown, you can use the stats command, which provides a clean and efficient way to calculate values without generating unnecessary output.

Steps to Implement the Solution

Check Your Gnuplot Version:
Make sure you are using Gnuplot version 4.6.0 or later. You can easily check your version by running the command:

[[See Video to Reveal this Text or Code Snippet]]

Utilize the stats Command:
You can fetch statistical properties directly from your data file using the stats command. Here's how to do it:

[[See Video to Reveal this Text or Code Snippet]]

In this code:

You call stats on your data file where u 1:2 indicates the columns you want to analyze.

The nooutput option ensures that there is no graphical output, thus preventing the terminal warning.

You can then calculate the dimensions by using the calculated statistics with easy access to the STATS variables.

Benefits of This Approach

No More Warnings: By utilizing the stats command, you eliminate the warning about the unknown terminal.

Efficient Computation: You can efficiently compute desired statistical values without cluttering your output with unnecessary plots.

Legacy Support: This approach works with versions of Gnuplot starting from 4.6.0, making it widespread and accessible.

Conclusion

The WARNING: Plotting with an 'unknown' terminal can disrupt your workflow in Gnuplot, especially during data computations where graphics are unnecessary. By replacing the set terminal unknown command with the stats command, you can easily and quietly obtain the data you need without the annoying warnings.

Enjoy a smoother Gnuplot experience with less hassle!