A Harmonic analysis result can be expressed using the following complex notation:
 | (5–1) |
The amplitude is calculated as:
 | (5–2) |
You can verify Equation (2) for component results, such as a Directional Deformation, by solving the equation using the real and imaginary components of the given result.
Amplitude of a Derived Result
A derived result is computed from the component results. For example, Total
Deformation, 
, is a derived result because it is evaluated from the displacement
components 
, 
, and 
in X, Y, and Z directions, respectively, as shown in the following
equation:
 | (5–3) |
For derived results, the following procedure is employed to calculate Amplitude. Using the formula for a particular derived result, the real and the imaginary parts of the derived quantity are evaluated from the real and imaginary component results respectively. The Amplitude for the derived result is then calculated using Equation (2).
For example, the Amplitude of Total Deformation is calculated using the formula for Total Deformation, shown here:
 | (5–4) |
 | (5–5) |
The Amplitude of Total Deformation:
 | (5–6) |
Caution: Note that for the Amplitude results for Minimum, Middle, and Maximum Principal Stresses, the application sorts the three values from highest to lowest before it reports the results. To illustrate this, consider real and imaginary values for Minimum, Middle, and Maximum Principal Stresses, as S1, S2, and S3, at a certain node and frequency. You obtain the result values by setting the Sweeping Phase property to 0 and 90 degrees respectively. The table below shows application generated result values for this example. The amplitude values do not correspond, as applicable to Equation (2), for the real and imaginary components. This is because the application sorts the three amplitude values from highest to lowest, before reporting the result values.
| Result | REAL (Phase = 0°) | COMPLEX (Phase = 90°) | AMPLITUDE |
| S1 | 3142.8 | 1.92E-13 | 3142.8 |
| S2 | -124.39 | -7.62E-15 | 145.8 |
| S3 | -145.8 | -8.93E-15 | 124.39 |