Allow more math operations than one and support fractions input
It's handy when in Illustrator you have units set to picas and you input pixels just by adding the px, but not so handy when you need to add a fraction and because you don't know you have to calculate the value first, instead of for example typing 1+9/16 and not 1.5625.
Other example is when you're setting guides or dividing grids: you need to break a space in x times or create a pattern.
CorelDraw has it and saves a huge chunk of time.
Right now, we can perform simple calculations inside numerical fields. For example, if I want to set the width of an object to 48% of 12", I can enter in: "12 * 0.48" in the field and it will evaluate the statement before applying the result to the width. This functionality saves us a ton of time since we can calculate values that we would normally be doing on a physical or digital calculator.
I would like the ability to perform more complex calculations in this way, such as: "17.5 * (2/3) + 0.25"
B Smart commented
Are you aware that all of the shape and transformation tools have calculation built in? For instance, you can click the ellipse tool (or pretty much any tool that gives you an input box) and enter 12/3 in the width box. it will give you a width of 4. Or if you want to repeat a Rotate>Copy put 360/3 in the Angle input box and it will give you 120 degrees. Very useful.
Brad Sims commented
A simple calculator panel to basic math. This would be great in ALL Adobe products, in fact.
AI (at least on Windows) allows one operation at a time, and I wish it could allow more. But William says like if it doesn't work for him at all. Is it?