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Calculations are normally performed numerically wherever possible.
For example, the `calc-sqrt`

command, or `sqrt`

function in an
algebraic expression, produces a numeric answer if the argument is a
number or a symbolic expression if the argument is an expression:
`2 Q` pushes 1.4142 but `' x+1 RET Q` pushes ‘`sqrt(x+1)`’.

In *Symbolic mode*, controlled by the `m s` (`calc-symbolic-mode`

)
command, functions which would produce inexact, irrational results are
left in symbolic form. Thus `16 Q` pushes 4, but `2 Q` pushes
‘`sqrt(2)`’.

The shift-`N` (`calc-eval-num`

) command evaluates numerically
the expression at the top of the stack, by temporarily disabling
`calc-symbolic-mode`

and executing `=` (`calc-evaluate`

).
Given a numeric prefix argument, it also
sets the floating-point precision to the specified value for the duration
of the command.

To evaluate a formula numerically without expanding the variables it
contains, you can use the key sequence `m s a v m s` (this uses
`calc-alg-evaluate`

, which resimplifies but doesn’t evaluate
variables.)