! scope="col"| Observable Type
! scope="col"| Applications
! scope="col"| Restrictions
|-
| style="width:150px;" | '''[[Glossary of EM.Cube's Simulation Observables#Near-Field Sensor |Near-Field Distribution Maps]]'''
| style="width:150px;" | '''[[Glossary of EM.Cube's Simulation Observables#Near-Field Sensor |Near-Field Sensor]]'''
| style="width:300px;" | Computing electric and magnetic field components, electri scalar potential and magnitude of magnetic vector potential on a planar cross section of the computational domain
|-| style="width:150px;" | '''[[Glossary of EM.Cube's Simulation Observables#Field Integral |Field Integral Quantities]]'''| style="width:150px;" | '''[[Glossary of EM.Cube's Simulation Observables#Field Integral |Field Integral]]''' | style="width:250px300px;" | NoneComputing line, surface and volume integrals of the electric and magnetic fields
|}
Click on each category to learn more details about it in the [[Glossary of EM.Cube's Simulation Observables]].
<table>
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<td> [[Image:Qsource9.png|thumb|360px|Electric field distribution of a spherical charge on a horizontal field sensor plane.]] </td>
<td> [[Image:Qsource10.png|thumb|360px|Electric scalar potential distribution of a spherical charge on a horizontal field sensor plane.]] </td>
</tr>
</table>
=== Defining Field Integrals ===
It is often needed to compute integrals of the electric or magnetic fields to define other related quantities. The following table shows some of widely used field integrals in electrostatics and magnetostatics. In EM.Ferma, you can define a path integral along a line segment that is parallel to one of the three principal axes, or a loop integral on a rectangle that is parallel to one of the principal planes. You can also define flux planes or flux boxes. All this is done from the same Field Integral Dialog. To define a Field Integral, right-click on "Field Integrals" in the Navigation Tree and select "Insert New Observable..." from the contextual menu. The Integral Type drop-down list gives nine options as listed in the table below:
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<table><tr> <td> [[Image:Qsource13Qsource9.png|thumb|400px360px|Defining the capacitance observable in the Field Integral dialogElectric field distribution of a spherical charge on a horizontal field sensor plane.]]In the above table, C represents an open curve (path), C<sub/td>o</subtd> represents [[Image:Qsource10.png|thumb|360px|Electric scalar potential distribution of a closed curve (loop), S represents an open surface like spherical charge on a horizontal field sensor plane, S.]] <sub/td>o</subtr> represents a closed surface like a box, and V represents a volume. In the case of mutual inductance, S' represents an open surface or plane passing through the second (coupled) inductor, and Φ'<sub>H</subtable> represents the magnetic flux linkage due to the magnetic field of the first inductor passing through the second inductor. The domain of the field integral is set using the "Integration Box Coordinates" section of the Field Integral dialog. Box domains are specified by the coordinates of two opposite corners. Voltage Path requires a line; therefore, two of the coordinates of the two corners must be identical. Otherwise, an error message will pop up. For example, (0, 0, 0) for Corner 1 and (10, 0, 0) for Corner 2 define a Z-directed line segment. Current Loop requires a rectangle; therefore, one of the coordinates of the two corners must be identical. For example, (0, 0, 0) for Corner 1 and (10, 10, 0) for Corner 2 define a rectangle in the XY plane. After the completion of a static simulation, the result of the field integrals are written into ".DAT" data files. These files can be accessed using [[EM.Cube]]'s Data Manager.
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<td> [[Image:Qsource13.png|thumb|left|480px|Defining the capacitance observable in the field integral dialog.]]</td></tr> <tr> <tr> <td> [[Image:Qsource11.png|thumb|360pxleft|480px|The electric flux box for calculation of charge around a capacitor.]] </td></tr> <tr><td> [[Image:Qsource12.png|thumb|360pxleft|480px|A line defining the voltage path for calculation of voltage between capacitor plates.]] </td>
</tr>
</table>