Points
Points is a Data manager object type for storing scattered point data - for example scatter points, culture points, measured values or computed results. Each Points object (point set) stores an X and Y coordinate for every point plus any number of user-defined attributes such as Z, time, porosity or velocity.
Purpose
A Points object is a table of points. Every point always has the two required plan coordinates and can carry an unlimited number of additional attributes:
- X and Y - the required plan coordinates of each point.
- Attributes - any number of extra columns (for example Z, time, porosity, velocity), each with its own name and data type.
Each attribute has one of three data types, chosen in the Add attribute dialog:
- Int - whole-number (integer) values.
- Float - floating-point (double) values.
- String - free text (up to 50 characters).
Creating and loading Points
A Points object is created by importing an ASCII text file. In the Data manager, right-click the Points branch (or a user folder inside it) and choose Import from ASCII..., then select the text file.
[image: placeholder_Data_manager_Points_node_context_menu_wi.png]
The Import points column-mapping wizard opens. Set the separator, header row and start row, map the first two columns to X and Y (both required), map the remaining columns to attribute fields and pick a type for each, and enter a Set name.
[image: placeholder_Import_points_column-mapping_wizard_with.png]
Supported input formats are comma-separated (.csv), tab-separated (.tab) and plain text (.txt) files. The file has a header row of field names followed by one row per point; the first two columns are X and Y and the rest become attributes:
- X Y Z Porosity
- 512340.0 6017820.0 1875.4 0.18
Point sets can also be exchanged in RESQML through the Import from RESQML EPC... and Export all to RESQML EPC... commands. See also Import points.
Attributes
Right-click a point set to manage its schema. Add attribute... opens a dialog with a Name field and a Type list (Int, Float, String; default Float). Existing attributes can be renamed or removed. The same set context menu also offers Rename set..., Duplicate set and Delete set.
Any point set can also tag individual attributes with a display role through the context-menu submenus:
- Set attribute for time - the chosen attribute supplies the time (Z) value, so the points are positioned in time on 3D views and seismic sections.
- Set attribute for depth - the chosen attribute supplies the depth (Z) value for depth-domain display.
- Set attribute for value - the chosen attribute drives the colour (palette) of the points.
Only numeric attributes (Int or Float) can take these roles; String columns are not offered. Choosing the attribute that already holds a role clears that role.
[image: placeholder_Set_attribute_for_time_/_depth_/_value_s.png]
Viewing and editing
A point set is shown in the Table view as a grid whose first two columns are X and Y, followed by one column per attribute. Editing a cell updates the point immediately, and coordinate edits refresh the map, section and 3D displays.
[image: placeholder_Table_view_of_a_Points_object_with_X,_Y_.png]
Points are also drawn on maps and seismic sections. When an attribute is assigned the time or depth role the points appear at the correct Z on sections and in 3D; when an attribute is assigned the value role the points are colour-coded by it.
[image: placeholder_Points_displayed_and_coloured_by_their_v.png]
Using Points
Point attributes behave like Marker attributes, so they can be reused elsewhere in g-Space:
- Calculator - attributes can be referenced in the calculator the same way as marker attributes, to derive new values or filter points.
- Cross-plots - any two attributes can be plotted against each other in a cross-plot to inspect trends and correlations.
[image: placeholder_Cross-plot_of_two_point-set_attributes.png]
Exporting Points
Right-click a point set and choose Export to ASCII... to write it to a delimited text file. The header row lists X, Y and every attribute name, and each following row is one point. Choose Tab separated values (*.tab) or Comma separated values (*.csv); full double precision is preserved so import - export - import round-trips are lossless.
The whole Points branch can also be written with Export all to RESQML EPC.... See also Export points.
Recommendations
- Keep X and Y in a consistent coordinate reference system and units across all point sets.
- Choose the smallest adequate type: Int for counts or codes, Float for measurements, String for labels.
- Assign a Set attribute for time or Set attribute for depth attribute before displaying points on sections so they land at the correct Z.
- Assign a Set attribute for value attribute to colour-code points by the property of interest.
- Use Duplicate set before bulk edits to keep an untouched copy of the original data.
See Also