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copied!<p>Here's an ugly solution using <code>RegionPlot</code>. Open limits are represented using dotted lines and closed limits with full lines</p> <pre><code>numRegion[expr_, var_Symbol:x, range:{xmin_, xmax_}:{0, 0}, opts:OptionsPattern[]] := Module[{le=LogicalExpand[Reduce[expr,var,Reals]], y, opendots, closeddots, max, min, len}, opendots = Cases[Flatten[le/.And|Or->List], n_<var|n_>var|var<n_|var>n_:>n]; closeddots = Cases[Flatten[le/.And|Or->List], n_<=var|n_>=var|var<=n_|var>=n_:>n]; {max, min} = If[TrueQ[xmin < xmax], {xmin, xmax}, {Max, Min}@Cases[le, _?NumericQ, Infinity] // Through]; len = max - min; RegionPlot[le && -1 < y < 1, {var, min-len/10, max+len/10}, {y, -1, 1}, Epilog -> {Thick, Red, Line[{{#,1},{#,-1}}]&/@closeddots, Dotted, Line[{{#,1},{#,-1}}]&/@opendots}, Axes -> {True,False}, Frame->False, AspectRatio->.05, opts]] </code></pre> <p>An example reducing an absolute value:</p> <pre><code>numRegion[Abs[x] < 2] </code></pre> <p><img src="https://i.stack.imgur.com/pOwo6.png" alt="example 1"></p> <p>Can use any variable:</p> <pre><code>numRegion[0 < y <= 1 || y >= 2, y] </code></pre> <p><img src="https://i.stack.imgur.com/5GfC5.png" alt="example 2"></p> <p><code>Reduce</code>s extraneous inequalities, compare the following:</p> <pre><code>GraphicsColumn[{numRegion[0 < x <= 1 || x >= 2 || x < 0], numRegion[0 < x <= 1 || x >= 2 || x <= 0, x, {0, 2}]}] </code></pre> <p><img src="https://i.stack.imgur.com/6d7ox.png" alt="example 3"></p>

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