# Category Archives: Coordinate Geometry

## Update to Glob_to_loc3 and Loc_to_glob3 functions

Following a comment here I have updated the Glob_to_loc3 and Loc_to_glob3 functions to deal with some problems when the local longitudinal axis is parallel to the global Y or Z axes.  The IP2 spreadsheet, including the revised functions, can be downloaded from: … Continue reading

## Nearest Lookup Function

The Excel Lookup functions (including VLookup, HLookup and Match) all allow for an “exact” or “closest” match on numerical data, but the closest option has a number of problems: The data must be sorted For VLookup and HLookup the data … Continue reading

Posted in Coordinate Geometry, Excel, Maths, UDFs, VBA | | 2 Comments

## IP2 and IP2_py

The IP2 spreadsheet provides functions to calculate: Intersection points of 2D lines or polylines Intersection points of 2 circles, or a line and a circle Intersection circle of two spheres and intersection points of 3 spheres 3D centre point of … Continue reading

## Dividing shapes into layers

For reasons that will become apparent in a later post, I need to rotate irregular polygons, defined by the coordinates of each corner, by a specified angle, and then split the resulting shape into horizontal trapezoidal layers. I have written … Continue reading

Posted in Coordinate Geometry, Excel, Maths, UDFs, VBA | | 8 Comments

## Global to Local for plates (and three node beams)

The Glob_to_Loc function (see Converting from global to local coordinates (and vice versa) ) converts forces and deflections of a beam from the global coordinate system to the local system, defined by the longitudinal axis of the beam and a rotation angle … Continue reading