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Update Post processing of velocity results authored by Guillaume Bodart's avatar Guillaume Bodart
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User-manual/Post-processing-of-velocity-results.md
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...@@ -54,7 +54,7 @@ The steps of the median test are as follows: ...@@ -54,7 +54,7 @@ The steps of the median test are as follows:
> It is possible that the median test will reject many vectors in the case of a **complex velocity field with large spatial gradients**. In this case, the ***epsilon*** parameter can be adjusted (e.g., 0.2 or 0.3). > It is possible that the median test will reject many vectors in the case of a **complex velocity field with large spatial gradients**. In this case, the ***epsilon*** parameter can be adjusted (e.g., 0.2 or 0.3).
> - For complex velocity fields, it is recommended to use a dense grid to limit spatial gradients. > - For complex velocity fields, it is recommended to use a dense grid to limit spatial gradients.
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The nearest neighbors are identified using a KD-Tree [(Bentley, 1975)](Manuel-utilisateur/Références-bibliographiques). The number of neighbors and the maximum distance to neighbors can be set as parameters. The nearest neighbors are identified using a KD-Tree [(Bentley, 1975)](Manuel-utilisateur/Références-bibliographiques). The number of neighbors and the maximum distance to neighbors can be set as parameters.
...@@ -140,7 +140,7 @@ The ratio between the peak width and the velocity vector norm is calculated. The ...@@ -140,7 +140,7 @@ The ratio between the peak width and the velocity vector norm is calculated. The
> A tolerance threshold of ***rhomax = 0.5*** means that the peak width should not exceed half (50%) of the calculated velocity norm. > A tolerance threshold of ***rhomax = 0.5*** means that the peak width should not exceed half (50%) of the calculated velocity norm.
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This filter analyzes the distribution of correlations around the peak. This filter analyzes the distribution of correlations around the peak.
...@@ -209,7 +209,7 @@ All velocities at the point (after passing through the previous filters) are use ...@@ -209,7 +209,7 @@ All velocities at the point (after passing through the previous filters) are use
Points with a circular variance greater than a **tolerance threshold of 0.25** are rejected (default parameter ***circvarmax = 0.25***). Points with a circular variance greater than a **tolerance threshold of 0.25** are rejected (default parameter ***circvarmax = 0.25***).
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The circular variance $circvar$ for a sample of $n$ observed angles $x_0, x_1,..., x_n$ is expressed as: The circular variance $circvar$ for a sample of $n$ observed angles $x_0, x_1,..., x_n$ is expressed as:
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