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Building a three-dimensional vector
Function
V3 is used in the RPN mode to build a vector with the values in
stack levels 1: , 2:, and 3:. The following screen shots show the stack before
and after applying function
V2:
Changing coordinate system
Functions RECT, CYLIN, and SPHERE are used to change the current
coordinate system to rectangular (Cartesian), cylindrical (polar), or spherical
coordinates. The current system is shown highlighted in the corresponding
CHOOSE box (system flag 117 unset), or selected in the corresponding
SOFT menu label (system flag 117 set). In the following figure the
RECTangular coordinate system is shown as selected in these two formats:
When the rectangular, or Cartesian, coordinate system is selected, the top
line of the display will show an XYZ field, and any 2-D or 3-D vector entered
in the calculator is reproduced as the (x,y,z) components of the vector. Thus,
to enter the vector A = 3
i
+2
j
-5
k
, we use [3,2,-5], and the vector is shown as:
If instead of entering Cartesian components of a vector we enter cylindrical
(polar) components, we need to provide the magnitude, r, of the projection of
the vector on the x-y plane, an angle
θ
(in the current angular measure)
representing the inclination of r with respect to the positive x-axis , and a z-
component of the vector. The angle
θ
must be entered preceded by the angle
character (
∠
), generated by using
~‚6
. For example, suppose that
we have a vector with r = 5,
θ
= 25
o
(DEG should be selected as the angular
measure), and z = 2.3, we can enter this vector in the following way:
