Formula Editor

What it is and why it exists

Requirements for brakes, sensors or control loops often need a formula: a stopping distance, a tolerance, a filter. DOORS Next has no formula editor. Teams paste a screenshot from Word, which nobody can change later without the original file, or type the formula as plain text, which is hard to read.

Formula Editor lets you write the formula in LaTeX inside DOORS Next. It draws the formula as you type and puts it into the module as a picture, either in a new artifact after the selected one or in the selected artifact. The LaTeX is saved with the artifact, so selecting the formula later opens it again in the editor.

Problems it solves

• Formulas pasted as screenshots that nobody can change without the Word file they came from.
• Formulas typed as plain text, such as s = v^2/(2*mu*g), that are hard to read in reviews and exports.
• Pictures of formulas that no longer match the text after one of them was changed by hand.
• Switching to another tool and copying pictures back for every new or changed formula.

Benefits

• See it as you type: the preview draws the formula while you write and shows the size of the picture.
• Changeable later: the LaTeX is kept in the artifact, so selecting a formula opens it again and Update draws a new picture.
• Text stays: Update on an artifact with text adds the formula after the text and keeps the words.
• No other web site: the formula is drawn in your browser by MathJax; it is not sent to an online editor.
• Errors with their place: a missing brace or an unknown command is shown under the field with the character where it is.

How to use

1. Open a module and select one artifact.
2. Type the formula in LaTeX, or click the keys under the field: fraction, root, power, index, sum, integral, Greek letter, plus minus and matrix. More symbols shows 21 more. The preview shows the picture and its size.
3. Click Insert to add the formula in a new artifact after the selected one, or Update to write it into the selected artifact. Read the confirmation and click Insert formula or Update formula.
4. The result block shows what was done, and Log downloads the change report.
5. To change a formula, select it in the module. It opens in the widget (Editing 1531 …); change the LaTeX and click Update.

Good to know

• Work in a change set, so you can discard it if the result is not what you wanted. The new artifact is saved right away.
• The picture is a PNG saved on the DOORS Next server, drawn at twice its size so it stays sharp on screens and in exports. Settings has three sizes: S, M and L.
• The LaTeX goes into an attribute named Formula when the project has one, and always into the picture description, so a formula opens again also in a project without that attribute.
• New artifacts get the type of the selected artifact. In Settings you can choose another artifact type of the project for Insert; the widget remembers it per project. Update keeps the type.
• When the picture of a formula was replaced by hand, the widget says so and the Update confirmation warns that the change will be lost. The LaTeX always wins.