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CrossPlot By Map compares two data sources spatially: a set of points carrying an attribute value, and a 2D map (matrix). For each point in the input point vector, the module samples the map at the point's XY location using bilinear interpolation. The point's own Z attribute is then paired with the sampled map value, and the resulting pairs are displayed as a scatter plot.
The module computes a linear least-squares regression line through the paired data and calculates the Pearson correlation coefficient. The regression line is overlaid on the scatter plot in the built-in viewer. Points that fall outside the map area (no valid map value at their XY location) are automatically excluded from the analysis. If an output file path is provided, all matched pairs are also exported to a tab-delimited ASCII file.
Note: This module is deprecated and may be removed in a future release. For new workflows, consider alternative cross-plotting tools available in the platform.
The 2D map (matrix) to use as the reference surface for the cross-plot. This is typically a seismic attribute map, a horizon amplitude map, an interval velocity map, or any other spatially gridded quantity. At each input point's XY location, the map is sampled using bilinear interpolation to obtain the map value for that location. Points falling outside the map extent are excluded from the analysis.
A collection of points with XYZ coordinates. The X and Y components define the geographic or grid location of each point, while the Z component carries the attribute value that is cross-plotted against the map. This input could represent well log values at specific locations, horizon picks, or any other spatially distributed attribute. The module iterates over every point in this collection and pairs each point's Z value with the interpolated map value at its XY position.
Optional path for an ASCII output file (.txt) where the matched point pairs are written. If a path is specified, the file is created in tab-delimited format with four columns: X (easting), Y (northing), Val1 (the point's Z attribute value), and Val2 (the interpolated map value at that location). Only matched points (those within the map extent) are written to the file. Leave this field empty if ASCII export is not required; the scatter plot and correlation coefficient are always computed regardless of this setting.
The Pearson correlation coefficient (r) between the point attribute values and the map values at the corresponding locations. This dimensionless scalar ranges from -1 (perfect inverse linear relationship) to +1 (perfect direct linear relationship). A value near zero indicates no linear correlation between the two datasets. The coefficient is computed from all matched point pairs that fall within the map extent.
After execution, the module's built-in viewer shows two overlaid datasets on a 2D scatter plot:
Scatter plot (VistaPoints): Each matched point is plotted with its Z attribute on the horizontal axis and the corresponding interpolated map value on the vertical axis. This lets you visually assess the degree of correlation between the two quantities across the survey area.
Regression line (VistaCorrLine): The best-fit linear regression line is displayed over the scatter plot, spanning the full range of the point attribute values. The slope and intercept of this line are derived from the same least-squares computation used to calculate the Pearson coefficient.