The SignQuery(expr) calling sequence displays a dialog that asks about the sign of expr. The user can click Yes or No. The return value is true or false, respectively.

The opts argument can contain one or more of the following equations that set Maplet application options.

height = posint

If the option mathml is set to true, this is the height of the MathMLViewer element. By default, the height is $50$ pixels.

mathml = true or false

If this option is set to true, the expression is rendered using MathML.

sign = positive, nonnegative, negative, nonpositive, or nonzero

This option adjusts the question posed. By default, the value is positive. That is, the query asks if expr is positive.

title = string or symbol

Specifies the Maplet application title.  By default, the title is Sign Query.

width = posint

If the option mathml is set to true, this is the width of the MathMLViewer element. By default, the width is $50$ pixels.

$\mathrm{with}\left(\mathrm{Maplets}\left[\mathrm{Examples}\right]\right)\:$

$\mathrm{SignQuery}\left(x^2-4\right)$

$\mathrm{SignQuery}\left(x^2-4\,\mathrm{mathml}\right)$