Chapter 11: Using the Measure Toolbox 11-7
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Calculate
The
Calculate
tool opens a calculator at the bottom of the screen. You can perform calculations
using measurements, numerical values, calculation results, and numerical inputs from the
keyboard. When you change the components of a calculation, the result is updated.
The calculator shown below is displayed at the bottom of your computer screen. It cannot be
moved from this position. Once selected, the calculator remains
ON
(visible) until you press the
OFF
button. The calculator becomes active as soon as you select the
Calculate
tool. It becomes
inactive when you perform any action not directly associated with a calculation. To reactivate the
calculator, you can either select the
Calculate
tool or click in the calculator edit window.
edit window
result window
Calculations are entered in the edit window. See the procedure “Entering a calculation” in this
section for how to enter a calculation. A measurement or numerical value from the Cabri
Geometry II drawing window is represented in the edit window as a variable
a, b, c, ..., z
. This
variable is also shown next to the value in the Cabri Geometry II drawing window. The value's full
precision will be used in the calculation. All parentheses must be closed when entering a
calculation.
You can extract the abscissa and ordinate from any coordinate set by clicking on each value
individually.
The calculation result is displayed in the result window. You can drag the result to the Cabri
Geometry II drawing window. When you drag the result to the drawing window, a tag identifying it
as a calculation result is dragged along with it. See the step for copying the result to the drawing
window in the procedure “Entering a calculation” on page 11-10.
You cannot modify values in the result window. However, on the Macintosh and Windows
versions, you can edit results using
Numerical Edit
once they are in the drawing window. In addition
to using the standard
Numerical Edit
features, you can display and change the composition of the
result by selecting the
Calc
option in the
Numerical Edit
window. For the DOS version, select the
Calculate
tool, and double-click on the result to get the original formula back in the edit window. If
you change the composition of a calculation, its result is automatically updated in the drawing
window. (See “
Numerical Edit”
in the chapter "Using the Display Toolbox" for more details.)
If two different but compatible units are involved in a calculation, the result is displayed with the
default units specified in
Preferences
under the
Options
menu (for example, 2 cm + 4 mm = 2.4 cm).
The calculator gives three types of warnings:
4
division by zero
4
parentheses not closed
4
incompatible units
Both
division by zero
and
parentheses not closed
must be corrected before the calculation can be
performed. For
incompatible units
, Cabri Geometry II offers the option to disregard the units and to
perform the calculation as if the values were without units.