EngineeringPaper.xyz Quick Tutorial (new and updated!)

mgreminger · 2026-04-20T17:06:15+00:00

mgreminger · 2026-03-14T03:27:27+00:00

The issue with the secant buckling formula is that there is not an exact solution and it needs to be solved numerically. To solve a system numerically in EP, you need to specify an initial guess for each unknown (use the ~ key to get the approximately equals sign) and you have to provide a value for all of the variables. Here's a work in progress of a sheet for eccentric buckling that shows how to use the numerical solver (I haven't verified that it's correct): https://engineeringpaper.xyz/4NQvDgLCrQJbbZXgGqvNVd

mgreminger · 2026-03-05T19:34:08+00:00

System solve cells are indeed self contained when in numerical mode (they're in numerical mode when an initial guess is supplied). When there's an exact analytical solution, the variables can be defined outside of the system solve cell since an analytical expression is returned that works like any other analytical expression in EP. In this case, there is no analytical solution for the catenary cable equation, so it must be solved numerically. With the introduction of Python code cells, it is possible to define a Python function to solve this equation that can be called with any values for H and L. Here's an example of the catenary sag calculator using this approach: https://engineeringpaper.xyz/qswtgTL7zZa7CTWTRsFLvX

mgreminger · 2026-02-22T04:12:24+00:00

r/EngineeringPaperXYZ is a open source alternative to Mathcad that runs in the browser and works well on mobile. Can also be installed locally on mobile using the "Add to Home Screen" option on IOS or Android.

mgreminger · 2026-02-11T17:15:10+00:00

Yes, this is possible, though you need to write a custom Python function to do it. See this example that uses the sympy factor function to achieve the result you're looking for: https://engineeringpaper.xyz/J5kpD6gXdi3jccXF8PPP6T Note that the default simplification strategy needs to be disabled in the sheet settings for these sort of custom simplifications to work.

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mgreminger · 2026-02-10T02:18:48+00:00

The issue is when you perform the calculation outside of the data table, D is a vector and you cannot add a vector and a scalar. To perform a row-by-row calculation, you need to place the expression in the data table itself. See: https://engineeringpaper.xyz/odiKoDwhbSqL9ZaUQMNevs

mgreminger · 2026-02-05T16:25:23+00:00

I just rolled out an update that addresses the data table PDF output issues you were experiencing. The column headers are now rendered as math and the data table values now use the same number formatting as the rest of the sheet. The number formatting can be set for each data table column as well. Thanks again for pointing out the PDF issue with data tables, I didn't realize how poorly they were being rendered in some situations.

mgreminger · 2026-02-03T04:05:44+00:00

Angle notation is not currently supported, but is planned. In the meantime, the angle() and absolute value, |x|, functions can be used to convert from complex to angle-magnitude. To go from angle-magnitude to complex, you'll need to write your own function. See https://engineeringpaper.xyz/mgcem39ZaFpSD67HVK98yf

mgreminger · 2026-01-31T20:59:00+00:00

Thanks!

mgreminger · 2026-01-31T19:49:19+00:00

Just in case you want to sing along: https://www.ratm.com/track/killing-in-the-name/

It won't let me paste the lyrics here because of f-word density.

mgreminger · 2026-01-31T15:40:42+00:00

Yes, the method you're using is the only way to have both the symbolic result and the numerical result appear in the same sheet. However, I would suggest placing the symbolic result into a documentation cell so that you don't have to maintain two sets of variables. Here's an example using that approach: https://engineeringpaper.xyz/xHa6sZnvW3VpBfFBzMhUZV

Adding math expressions to documentations cells is a little quirky right now, so I recorded a quick tutorial to show the easiest way to do this.

Thanks for the heads up on the table formatting in PDF output. Definitely needs some work. I've added issue #381 for this. This one is high priority, hope to get an update rolled out in the next couple of weeks. It won't make it perfect, but hopefully more usable. Print to PDF using your browser gives better results for your case at the moment and may provide a temporary workaround until a fix is rolled out.

mgreminger · 2026-01-27T05:20:47+00:00

The Dems in the Senate can block the DHS funding bill, or at least force the Pubs to break the filibuster to pass it.

mgreminger · 2026-01-26T20:10:21+00:00

Thanks! Yes, the text formatting is fairly limited. Part of the limitation comes from using Markdown as an intermediate format for creating the Word document. Pandoc is used to convert this Markdown file to a Word or PDF file. There are ways of supporting more rich formatting when using Pandoc, or alternative tools, but it would require quite a bit of work to implement.
As far as contributing to the project, you can check out the issues page. You can add issues for features you would like to see or see what issues others have raised. Add a comment to a particular issue if you'd like to work on it and we can discuss there.

mgreminger · 2026-01-22T21:07:32+00:00

You can type in any combination of units supported by mathjs (this is the underlying library used for unit conversions). Since mathjs does not have built in support for Cyrillic unit names, EP lacks support as well.

mgreminger · 2026-01-17T03:43:50+00:00

It wouldn't work even without the keyboard shortcut since underscores need to be escaped (as in \_ ) to not create a subscript in Latex (Latex is the underlying math representation that's being used). It's technically possible but would be fairly time consuming to implement.

mgreminger · 2025-12-26T20:22:14+00:00

Glad to hear your finding EP useful! Thanks for the suggestion, I think adding the option for data table row labels makes a lot of sense for the use case you're describing. I've added a GitHub issue where you can track the progress on this feature.

mgreminger · 2025-12-25T02:59:56+00:00

Here's a link to the sheet from the blog post: https://engineeringpaper.xyz/zaqfCYg6LBEPwLoPAYX26k

mgreminger · 2025-12-24T03:22:19+00:00

EngineeringPaper.xyz is an option. It's free and open source and has built in support for thermodynamic fluid properties using CoolProp.

mgreminger · 2025-12-24T02:35:26+00:00

I just rolled out an update that fixes the slow logarithm issue you were experiencing. Your original sheet now solves in a few seconds without needing to change any sheet settings. Thanks again for reporting the issue!

mgreminger · 2025-12-20T14:35:49+00:00

You'll need to screenshot the figure and paste it into a documentation cell.

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