Expressions and assignment

Click once on empty paper. A math region appears. Type, and the field draws as you go: a fraction looks like a fraction, an exponent sits where you expect. Underneath, Calculeaf stores the plain expression. The printed form is only how it is drawn.

Three operators that look alike

Token	Meaning	Example
:=	Define a name. Nothing prints unless you also ask for an answer.	w := 12 kN/m
= at the end of the line	Print the answer of the line in a chip after it.	R := w * L / 2 =
==	Compare two values and report true or false.	R == 24 kN =

Define a name

Type the name, then a colon. Calculeaf inserts := for you. You do not need both characters. If you then press = as well, the extra equals is ignored, so you do not end up with :==. Home → Settings has Show := as = if you would rather see a plain equals on the page; you still type a colon, and the stored expression is still :=. That option is off by default.

If you would rather click, the Math tab has it under Operators ▾ → Define. A name defined this way is visible to everything after it, which is the subject of variables and scope.

w := 12 kN/m
L := 6 m

Show the answer

Put = at the end of a finished line. Calculeaf evaluates the expression and draws the answer in a chip after it. Delete that = when you want the definition on the page but no number beside it. That is useful for a long list of inputs where only the final answer matters.

w := 12 kN/m =
R := w * L / 2 =

Press = a second time at the end of the line and Calculeaf rewrites the marker as ==, turning the line into a comparison. That is deliberate, and it is the same operator the ribbon inserts.

Compare two values

Write == in the middle of an expression, or use the = button in the Math tab's Compare group, which inserts == for you. The rest of that group covers ≠, <, >, ≤, and ≥, plus the logical ∧ and ∨ buttons, which insert and and or.

R == 24 kN =

One exception is worth knowing. Inside a Given/solve block a top-level = is read as a constraint rather than a request for an answer, so the same keystroke means something different there. Given and solve covers that workflow.

Operators, functions, and constants

Type them if you know them, or click them in:

• Algebra gives you +, −, ·, /, powers, roots, absolute value, factorial, and parentheses.
• Operators ▾ browses the same set by category and adds Matrix, Calculus, and Define.
• Functions ▾ is organised as Stats, Matrix, Trig, and More. The function catalog lists what each one takes.
• Constants holds π, e, ∞, and g, which is standard gravity at 9.80665 m/s².

Three shorthands round it out. ^ raises to a power. % is a real unit defined as 0.01, so 20% evaluates to a dimensionless 0.2 rather than the number twenty. Anything after // on a line is a comment and is ignored.

One expression per region

A math region holds a single expression. The ↵ marker under Operators ▾ → Define wraps the display onto a second line. It does not start a second statement. To carry on calculating, press Enter after an assignment. Calculeaf places the next math region below and runs Evaluate All.

Next, variables and scope so you know which regions can see the name you just defined.