Stack manipulation.

The following routines are used to directly modify the order of the data stored in the global Tina stack data structure. These are sufficient to allow the construction of any mathematical expression and therefore any image processing algorithm.

• C - remove top image (TOS) from stack.
• CA - remove all images from stack.
• store - save TOS in the storage register. Additional storage can be obtained via push and pop facilities in many of the other TINA sub-tools.
• fetch - retrieve image from the storage register.
• dup - duplicate TOS.
• flp - flip TOS with next image on stack (NOS).
• roi - edit TOS to selected roi. If a polygonal region has been selected in any Tv window within TINA this will be used to define the region of data. Values external to this polygon will be set to zero. If the polygonal region is selected within the imcalc Tv the maximum and minimum etent of the polygon vertically and horizontally will be used to define the new image dimensions. Full image dimensions can be restored by ``init"ing the imcalc Tv before using roi.