Tikal-25 Manual - Features and Functions
Input method calculating problem entry in algebraic order
64 Calculator functions:
| Aritmhmetic |
+,-,×,÷ |
4 |
| Data Entry |
+/-,π,rnd (random number in the range [0..1]) |
3 |
| Format |
Scientific notation,scientific notation removal |
2 |
| Algebraic |
x²,²√x,1/x,xy,x√y,x! |
6 |
| Clearing |
Clear input, clear all |
2 |
| Grouping |
Open and close parentheses, algebraic hierarchy |
3 |
| Memory |
Store, Recall, Sum, Exchange |
4 |
| Percentage |
%,+%,-%,×%,÷% |
5 |
| Trigonometry |
sin, cos, tan, asin, acos, atan, sinh, cosh, tanh, asinh, acosh, atanh, Degree, Radian, Gon/Gradian |
15 |
| Logarithmic |
ln x, log10, ex, 10x, logy x, yx, log2, 2x |
8 |
| Constants |
operates with +,-,×,÷,yx,x√y |
6 |
| Functions |
operates with up to three variables x, y, z. Multiple functions may be defined. |
1 |
| Statistics |
∑+,∑-,x̅,Variance,σ |
5 |
| Total |
|
64 |
When = is pressed, all pending calculations are terminated and the result is displayed. = implicitly closes all open parentheses, which can be used as a shortcut when keying in a problem.
The accuracy is at least 64bit floating point numerals, where 8 decimals are displayed. When a result is used in the following calculation, the full accuracy is used even if only 8 digits are displayed. Arithmetic functions use Decimals internally, the transcendental functions work with Double, which may produce rounding errors. This is caused by the fact that the underlying software mathematics library for these functions operate with the Double type. This shoul dnot pose any problem since the rounding error wil still be insignificant for the type of calculations this emulator is aimed at. It only displays 8 digit numbers in the end.
Localization
Different from the original, this emulator is being prepared for localization. Up to now, only a few parts will actually have some localized items, such as the OFF key and some texts in the additional views. Since it takes a lot of effort to do good localized features in a user interface, this will be completed later on in case there is any serious demand.
Keyboard Description
Level I
- CLR - Clear - (see Input correction below)
- I - Level - switch function levels I, II, ...
- 0-9 Digit keys - Enter numbers
- . - Decimal point key - enter the decimal point
- +/- - Change sign key - changes the sign of the number, or, when scientific notation input is engaged using EE, change hte sign of the exponent
- π - Enters π as the Decimal.pi constant
- +,-,×,÷ - Perform the respective arithmetic operation on the displayed value with the next entered value. Completes any previous ×,÷,yx,y1/x operation
- = - Equals key. Completes all number input and pending operations and displays end result that may be used for further calculations.
- 2nd K - Constant operation - stores a number and an operation for repeated calculations. See below.
- ( ) - Parentheses, compute partial result first
- yx - y to the xth power - raise the displayed value to the next entered number
- x2 - Calculate the square
- INV x2 - Calculate the square roor
- 1/x - Recirpocal value
- 2nd rnd - Enter a random value from the closed range [0..1].
- 2nd x! - Factorial of the displayed number. Must be an integer within the range 0..69
- % - converts displayed value to a percentage
- ln - Natural logarithm of the displayed value
- lg - Common logarithm (base 10) of the displayed value
- DRG - Switch the scope of trigonometric functions between degree, radian and gon/grad
- INV/2nd - switch to inverse or second level functions. (arcus for trigonomic functions, root for power functions, faculty for RND)
- sin, cos, tan - Trigonometric functions. The entered value is interpreted according to the selected scope. 360º degrees is the default scope. Internally, results are calculated with radian, so with degree and gon a conversion takes place internally which may produce minuscule rounding errors.
- EE - Allows entering exponent for scientific format and switches to scientific notation output mode
- INVEE - Switches off the scientific notation output mode and returns to normal floating point display for numbers that can be displayed with 8 digits after rounding
- STO - Store the currently displayed value to memory. Stores the full Decimal, not the displayed representation.
- RCL - Recall value from memory as current input value
- SUM - Add currently displayed value to stored value
- EXC - Exchange current value with stored value in memory
- ∑+ - Register the displayed value as statistic sample and activate statistics mode. Displays the number of entered samples
- 2nd ∑- - Cancel the last entered displayed value, if any. Displays the number of remaining samples.
- 2nd x̅ - Mean value of statistic samples
- 2nd VAR - Variance of statistic samples using N weighting
- 2nd SD x2 - Variance of statistic samples using N - 1 weighting
- 2nd SD - Standard deviation of statistic samples using N - 1 weighting
- 2nd VAR INV x2 - Standard deviation of statistic samples using N weighting
- ⌥ - Option symbol in header line - Press anywhere in the header line to access additional information displays: Statistics, Logfile, Manual,...
Level II
- sinh, cosh, tanh - Hyperbolic trigonometric functions. Scope as with other trigonometric functions.
- lb - Binary logarithm (base 2) of the displayed value
- log y - General logarithm (base y) of the displayed value
- 2nd x? - Recall variable x value - can be used in function definition
- 2nd y? - Recall variable y value - can be used in function definition
- 2nd z? - Recall variable z value - can be used in function definition
- 2nd DEFN - Start entry of function definition - end with =
- x= - Set variable x to currently displayed number
- y= - Set variable y to currently displayed number
- z= - Set variable z to currently displayed number
- fn - Invoke the defined function with the currently displayed number index. 0 fn invokes function 0
When ∑+ is used, the calculator enters statistics mode. STAT is displayed in the status display and arithmetic functions are blocked until CLR is pressed twice to cancel statistics mode.