Gri: axis scaling

Chapters: 1: Introduction 2: Simple example 3: Invocation 4: Finer Control 5: X-Y Plots 6: Contour Plots 7: Image Plots 8: Examples 9: Gri Commands 10: Programming 11: Environment 12: Emacs Mode 13: History 14: Installation 15: Gri Bugs 16: Test Suite 17: Gri in Press 18: Acknowledgments 19: License Indices: Concepts Commands Variables | ## 4.2: Axis scaling Gri normally assumes that you are plotting scientific graphs, and therefore whenever it sees a command like ``draw curve`' or ``draw symbol`', it draws an appropriate axis first. You can turn this feature off, by using ``draw axes none`' before the other ``draw`' command. Furthermore, Gri picks axis scales by itself, by scanning the (``x`', ``y`') columns. If you don't like the scales Gri picks, you can override them (see Range). Gri normally draws axes labelled at left and bottom, and with an axis frame with tics all around. If you don't like this default axis style you can specify other styles. For example, if the commands ``draw x axis`' and ``draw y axis`' are placed before the ``draw curve`' command, Gri will realize you've already specified axes, and just draw them on the left and bottom sides of the box, without completing the axis frame. For your general use, Gri stores the minimum and maximum x and y values of the axes in the variables ``..xleft..`', ``..xright..`', ``..ybottom..`', and ``..ytop..`'. It also stores the increments used in labelling these axes in the ``..xinc..`' and ``..yinc..`' variables. To determine the minimum and maximum values of column data, you may use the built-in RPN functions ``min`', ``max`', and ``mean`' (see Manipulation of Columns etc). Gri stores the last (x,y) pair on a curve (whether data or axis) in the ``..xlast..`' and ``..ylast..`' variables Gri stores the axis sizes in ``..xsize..`' and ``..ysize..`'. It stores the space to the left of the plot in ``..xmargin..`' and the space below the plot in ``..ymargin..`'.