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Manual iPad v.1.4

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Enter your text in input line, then tap [Ent] to proceed the calculation. When the width of calculation result is too wide, page number such as 0: appears at the most left, and the succeeding pages can be displayed by tapping inside calculation result. 

At the right of the calculation result, button [n] changes the format. By tapping the button, [n] is changed to [f], [f] is changed to [e], and [e] is changed to [n]. Formats can be redefined by [settings].

[n] normal format,  automatically choose shorter one between f and e formats

[f] decimal notation of the form mmm.ddd, example: -0.772643

[e] decimal notation of the form m.ddddddexx, example: -7.72643e-1


Delete one character of text before cursor in input line (backspace)


Clear all text in input line


Enter text in input line using software keyboard. To hide software keyboard, tap [done].


Recall previous text in input line to confirm, edit and recalculate the previous calculation.


Recall next text in input line.


Picker appears to select variable. Choose variable, then tap [done]. If you want to escape picker without selection, tap [BS]. When you defined your own variable, the name appears in the picker, and you can use it through picker. Predefined variables are Ans and pi. Ans means the previous calculation result. pi is the ratio of the circumference of a circle to its diameter (3.14..).


Picker appears to select function. Choose function, then tap [done]. If you want to escape picker without selection, tap [BS]. When you defined your own function, the name appears in the picker, and you can use it through picker. Predefined functions are abs (absolute value), sqrt (square root), exp (exponential), ln (natural logarithm), log (common logarithm), sin, cos, tan (trigonometric functions), asin, acos, atan (inverse trigonometric functions), int (largest integer not greater than x), and round (nearest integer).

[edit x,f(x)]

Edit user defined variables and functions. Tap the variable or function name, then the content is transferred to input line, which can be edited freely. If you want to delete variable or function, tap green button to change it to gray button. To effect the change, tap [done]. If you want to escape without deleting any variables and functions, tap [BS].


Font size: change the font sizes of input line and calculation result. The font size is between 10 and 40. If two figures are set with space separator, the first figure is for portrait view and the second figure is for landscape view. The font size of calculation result can be specified by min-max range, for example, 20-28. Most suitable font size is employed within the range. 

Format: change the format of calculation result.

   , : thousands separator format
   t : engineering notation
   - : left adjustment
   + : number will always be printed with a sign
  More than one flags can be specified, for example, ',t'.
  The width of field. If the width is shorter than the required width to display, the necessary minimum width is used.
  In f and e format, the number of digits following decimal point. In g format, the total number of digits. The default value is 6.
   f, F: decimal notation of the form [-]mmm.ddd, where the number of 's is specified by the precision. The default precision is 6; a precision 0 suppresses the decimal point. When base is greater than 10, alphabet is used to represent number greater than 10, a means, b means 11, etc. If format f is specified, lower case letter is used. If format F is specified, upper case letter is used.
   e, E : decimal notation of the form [-]m.ddddddexx or [-]m.ddddddExx, where the number of 's is specified by the precision. The default precision is 6; a precision of 0 suppresses the decimal point.
   g, G : %e or %E is used if the exponent is less than -4 or greater than or equal to the precision; otherwise %f is used. Trailing zeros and a trailing decimal point are not printed.



File: Load file for text in input line and 2nd key assigment through Internet. As an example, make the following web file.

<html> <records>

Enter the URL and tap [load], then a function sinh(x) and a 2nd key % are defined. The text in input line must be between <slcalc> and </slcalc>. Do not use characters '<' and '>' in the text of input line.

Angular Unit: angular unit of trigonometric functions, [rad] (radian) or [deg] (degree).

[significant digits]

Arbitrary precision up to 256 significant digits  are supported. When [Precision] is set less than and equal to 13, precision becomes 13, the maximum number available is 1e308, and the calculations become faster.  When [Precision] is set greater than and equal to 14, precision becomes the set value and the maximum number available is 1e646456993.

[dimension of variable]

Arrays of variables and functions are supported. Any dimension is possible.

[number of arguments in function]

The maximum number of arguments is 8.

[Upper/Lower case letter]

Calculation itself is no case sensitive. The name of variable or function is stored as it is, when registered at first time.


Comment can be inserted between { }. For example,

q = 1.60217733E-19 { elementary charge [C] }


Space, tab, and new line work as delimiter or are neglected, depending on the situation. The former example is "x=3 y=x-1", and the latter example is "x = 3 * y".  If the meaning changes when space or tab or new line is removed, it is delimiter. If you want to use delimiter intensionally, use ':' or ';'.


After digits, you can add the following units. T (1e12), G (1e9), MEG (1e6), K (1e3), m (1e-3), u (1e-6), n (1e-9), p (1e-12), f (1e-12), a (1e-18). For examples, 2.7p means 2.7e-12, 0.015G means 1.5e7.

[base of number]

For the text in input line, you can use 

0b_._ : binary number, example: 0b1011.11 = 11.75

0o_._ : octal number, example 0o123.456 = 83.58984375

0x_._ : hexadecimal number, example 0xffff = 65535

0ndn_._ : base of d.  example: 0n12n3ba.2 = 57.41666...

For the calculation result, add "/d" at the end of [format] in [settings].

example : Format : %6.2f/16

0x3f2.23f + 0xaf4d.edf becomes 0xb340.12

You can also define format as %6.2f/b (binary), %6.2f/o (octal), %6.2b/x (hexadecimal).

[name of variable and function]

The first character must be alphabet. The succeeding characters are digit or alphabet. Any length can be used, but the first 64 characters are distingushed.

Temporally variables and functions can be used  using name which starts $, and the succeeding characters are digit or alphabet. Temporally variables and functions do not appear in [x], [f(x)], and [edit x, f(x)], and are deleted after tapping [done] in [edit x,f(x)].

[predefined functions]

sin, cos, tan, asin, acos, atan, exp, sqrt, ln, log, abs, int, round

[recursive definition of function]

possible. The following function gives the factorial of n.

f(n) = if n gt 1 then n*f(n-1) else 1


 from higher to lower priority

    1) (   )
    2) NOT
    3) ^
    4) *   /    %
    5) +   -
    6) GT GE LT LE
    7) EQ   NE
    8) AND
    9) OR
  11) =

^: power 
GT: greater than 
GE: greater than or equal to 
LT: less than 
LE: less than or equal to 
EQ: equal 
NE: not equal

[logical value ]

result:  true = 1  false = 0

evaluation: true if not equal to 0, false if equal to 0


means substitution. The left hand side must be the name of variable or function.

[if then else]

if expression1 then expression2 else expression3  If expression1 is true, expression2 is evaluated, otherwise, expression3 is evaluated. The resulting value is the evaluated value.


while expression1 expression2  Expression2 is continued to be evaluated while expression1 is true.


You can write down several expressions, and the result is the final evaluated value. For example, 2*(x=2 y=3 x/y *5-1) becomes 14/3.This is useful for defining function. An example is shown below

    if (x ge 0) then y else 2-y

[predefined words]