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      <div class="title_topic2" id="xps10_pagetitle">Examine Geometry related topics</div>
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               <p class="para_td"><a class="links" href="javascript:void(0)" onclick="top.openFile('nx_analysis/ana_examgeom_ht.html');return(false);">How To</a></p>
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               <p class="para_td"><a class="links" href="javascript:void(0)" onclick="top.openFile('nx_analysis/ana_examgeom_r.html');return(false);">Options</a></p>
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               <p class="para_td">Related Topics</p>
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      </table><br><div class="title_division">Objects</div>
      <div class="title_division">Tiny</div>
      <p class="para_division">This function searches for all tiny bodies, faces, edges or curves in:</p>
      <ul>
         <li>
            <p class="para_item">curves, edges and bodies for which the diagonal length of a box enclosing the object is less than the specified distance tolerance</p>
         </li>
         <li>
            <p class="para_item">faces whose surface area is less than the specified distance tolerance, squared</p>
         </li>
         <li>
            <p class="para_item">faces whose area to perimeter ratio is such that 2 times the area, divided by the perimeter is less than the specified distance tolerance (this detects sliver faces)</p>
         </li>
      </ul>
      <p class="para_division">The number of incidences of tiny geometry is reported in the Information window. To highlight the tiny objects in the graphics window, click the Tiny option on the Highlight Results dialog.</p>
      <div class="title_division">Misaligned</div>
      <p class="para_division">This function checks all of the selected geometry that is close to being orthogonal with respect to the WCS, but is not exactly aligned with it. To check an ortho alignment with respect to some other coordinate system, change the WCS from the main menu bar. The test is made on lines, circles, planes, cylinders, cones, tori, swept and swung surfaces. For each object, a vector is obtained as follows:</p>
      <ul>
         <li>
            <p class="para_item">lines - a vector in the direction of the line</p>
         </li>
         <li>
            <p class="para_item">arcs and circles - a vector normal to the plane of the curve</p>
         </li>
         <li>
            <p class="para_item">planes - the normal vector</p>
         </li>
         <li>
            <p class="para_item">cylinders, cones, tori, surfaces of revolution - the axis vector</p>
         </li>
         <li>
            <p class="para_item">extruded surfaces - the extrusion vector</p>
         </li>
      </ul>
      <p class="para_division">Objects for which the vector is almost, but not exactly, parallel to XC, YC or ZC are flagged as misaligned.</p>
      <p class="para_division">The axis vector is considered to be misaligned if the angle in degrees is less than the input angle tolerance (the threshold tolerance), and the angle in radians is greater than a fixed resolution value of 0.0001.  Angles (e.g. 90 degrees) greater than the threshold tolerance are not considered for misalignment testing.  Angles less than the resolution tolerance are considered to be okay &ndash; no misalignment.</p>
      <p class="para_division">The number of incidences of misaligned geometry is reported in the Information window. To highlight the misaligned geometry in the graphics window, click the Misaligned option on the Highlight Results dialog.</p>
      <div class="title_division">Bodies</div>
      <div class="title_division">Data Structures</div>
      <p class="para_division">This function checks each selected body for data structure problems, such as corruption. The results are reported in the Information window. To highlight the invalid bodies in the graphics window, click the Data Structures option on the Highlight Results dialog.</p>
      <div class="title_division">Consistency</div>
      <p class="para_division">If you select this option, NX checks each selected body for inconsistencies.</p>
      <p class="para_division">This option will check:</p>
      <ul>
         <li>
            <p class="para_item">that the topological structure is consistent</p>
         </li>
         <li>
            <p class="para_item">that the geometrical objects are valid and that faces and edges have G1 continuous geometry</p>
         </li>
         <li>
            <p class="para_item">that the geometrical objects are consistent; that is, the point geometry of vertices lies on the edges and faces to which they are linked; that edge geometry lies in the faces to which they are linked; and that edges intersect only at vertices</p>
         </li>
      </ul>
      <p class="para_division">The results are reported in the Information window. Certain objects with inconsistencies are highlighted in the graphics window if requested from the Highlight Results dialog.</p>
      <div class="title_division">Face-Face Intersections</div>
      <p class="para_division">This function checks each selected body for face-to-face intersections, and that all faces of the selected body meet each other at their edges and nowhere else.</p>
      <p class="para_division">It is possible to inadvertently create face-face inconsistencies during modeling. For example, suppose you hollowed a cube to a thickness of 1mm, and then blended one of the outer edges to a radius of 5mm. The inner shell then intersects the outer shell, and the model is invalid.</p>
      <p class="para_division">Face-face inconsistencies can often be remedied by further modeling operations. In the above example, the model can be made valid by blending the inner edge.</p>
      <p class="para_division">The results of this test are reported in the Information window. Faces that intersect incorrectly are highlighted in the graphics window if requested from the Highlight Results dialog.</p>
      <div class="title_division">Sheet Boundaries</div>
      <p class="para_division">For sheet bodies only, the number of boundary loops&mdash;outer loops and inner (hole) loops&mdash;is reported.  These boundary loops can be highlighted from the <b class="uiTerm">Highlight Results</b> dialog.  The boundary loops and their number should be checked to make sure they agree with what is expected.
      </p>
      <div class="title_division">Faces</div>
      <div class="title_division">Smoothness</div>
      <p class="para_division">For faces whose surfaces are b-surfaces, Smoothness checks the b-surfaces to make sure the surfaces are smooth along their patch boundaries.</p>
      <p class="para_division">The results of the check are reported in the Information window. Any rough face is highlighted when requested from the Highlight Results dialog.</p>
      <div class="title_division">Self-intersection</div>
      <p class="para_division">This function performs a check for faces that self-intersect. The results of the check are reported in the Information window. Any self-intersecting face found is highlighted when requested from the Highlight Results dialog.</p>
      <div class="title_division">Spikes/Cuts</div>
      <p class="para_division">This function searches the selected faces for possible spikes or cuts. It does this by checking the angle between adjoining edges. When the angle is very small, the system checks several points along the shorter edge; if the distance between all of those points and the longer edge is less than the specified Distance Tolerance, that face is determined to have a possible spike or cut. The number of such faces is reported in the Information window. Each face found to contain a possible spike or cut is highlighted when requested from the Highlight Results dialog.<img align="bottom" src="graphics/ana_infofi16.gif" border="0"></p>
      <div class="title_division">Edges</div>
      <div class="title_division">Smoothness</div>
      <p class="para_division">This function searches for all edges whose adjoining faces do not join smoothly. The numbers of unsmooth edges are reported in the Information window. Each unsmooth edge is highlighted when requested from the Highlight Results dialog. </p>
      <div class="title_division">Tolerances</div>
      <p class="para_division">This function checks the tolerance of all of the selected edges against the value specified in the Distance tolerance field. The maximum edge tolerance found and the number of edges whose tolerance exceeds the specified tolerance is reported in the Information window. All edges with tolerance greater than the specified tolerances are highlighted when requested from the Highlight Results dialog.</p>
      <div class="title_division">All Checks</div>
      <p class="para_division">Set all checks selects all tests for the analysis and Clear All Checks deselects all the tests.</p>
      <div class="title_division">Threshold Tolerance Values</div>
      <p class="para_division">The Modeling Preferences dialog values are accessed by selecting Preferences&rarr; Modeling (while in the Modeling Application mode). The values that appear in the Distance and Angle fields are used as a benchmark for some of the Examine Geometry tests. You are free to enter your own values, which will persist through the rest of the session. </p>
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