I have created a spreadsheet for converting Cartesian (X,Y,Z) coordinate data for survey points into polar format survey legs (length, bearing, clino).

There is also a worksheet which converts back the other way. You want to enter your data (cut and paste it) in the columns which contain black example data. The blue cells are intermediate calculated values (useful to checking for mistakes). The green columns are the reformatted data ready to cut and paste into a Survex file or Therion centreline data file.

Here is the link to download the spreadsheet: CartesianPolarConversion.xls