Special Variables & Syntax

JS Calc includes special syntax to enhance your workflow.

Last Answer (@ or _ans)

The special variable @ (internally _ans for Math.js compatibility) holds the result of the last calculation that produced a displayable numerical, matrix, or unit value.

• Assignments (e.g., x=5) and function definitions (e.g., f(x)=x^2) do not update @.
• Example:

> 2+3
 5
> @ * 4
 20

---

> x=10 // notice no output when assigning
> @ / 2
 10
 // because we only assigned 10 to x which
 // did not change the @ from the previous solution

Implicit Last Answer

If an expression starts directly with one of the operators +, -, *, /, ^, %, JS Calc will automatically prepend the last answer (@) to the expression.

• Example:

> 100 / 4
 25
> + 75     // Evaluates as @ + 75  => 25 + 75
 100

• Note for leading minus (-): If @ has a value, typing - 5 will be interpreted as @ - 5. To enter a negative number directly when @ has a value, use parentheses (-5) or ensure the input field is clear.