Surfer can create vector plots from a grid file, or from two grid files individually containing direction and magnitude information. The 1-grid vector map calculates the slope or gradient direction from the Z values in the GRD file to draw vectors with magnitude and direction properties. The 2-grid vector map draws vectors based on two grid files containing the X and Y components, or the magnitude and direction components. I am a hard-rock exploration geologist...morphing into some oil and gas work, and I can see that your package is better than any of the usual ones we typically use in hard rock. Waaaay better. And affordable. And better supported.Lauri Boivin Keep up the good work with your ingenious, efficient, functional and cost effective software products. Dr. Lazaros Polymenakos Consultant Geologist-Geophysicist Copyright © 2016 Golden Software, LLC. All rights reserved. The names and logos for Surfer, Grapher, Voxler, MapViewer, Didger, Strater and Golden Software are registered trademarks of Golden Software, LLC. Source.