forked from KolibriOS/kolibrios
99 lines
2.2 KiB
Plaintext
99 lines
2.2 KiB
Plaintext
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(* ******************************************
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Дополнительные функции к модулю Math.
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Функции округления.
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Вадим Исаев, 2020
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-------------------------------------
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Additional functions to the module Math.
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Rounding functions.
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Vadim Isaev, 2020
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********************************************* *)
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MODULE MathRound;
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IMPORT Math;
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(* Возвращается целая часть числа x.
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Returns the integer part of a argument x.*)
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PROCEDURE trunc* (x: REAL): REAL;
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VAR
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a: REAL;
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BEGIN
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a := FLT(FLOOR(x));
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IF (x < 0.0) & (x # a) THEN
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a := a + 1.0
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END
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RETURN a
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END trunc;
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(* Возвращается дробная часть числа x.
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Returns the fractional part of the argument x *)
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PROCEDURE frac* (x: REAL): REAL;
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RETURN x - trunc(x)
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END frac;
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(* Округление к ближайшему целому.
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Rounding to the nearest integer. *)
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PROCEDURE round* (x: REAL): REAL;
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VAR
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a: REAL;
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BEGIN
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a := trunc(x);
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IF ABS(frac(x)) >= 0.5 THEN
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a := a + FLT(Math.sgn(x))
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END
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RETURN a
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END round;
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(* Округление к бОльшему целому.
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Rounding to a largest integer *)
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PROCEDURE ceil* (x: REAL): REAL;
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VAR
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a: REAL;
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BEGIN
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a := FLT(FLOOR(x));
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IF x # a THEN
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a := a + 1.0
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END
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RETURN a
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END ceil;
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(* Округление к меньшему целому.
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Rounding to a smallest integer *)
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PROCEDURE floor* (x: REAL): REAL;
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RETURN FLT(FLOOR(x))
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END floor;
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(* Округление до определённого количества знаков:
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- если Digits отрицательное, то округление
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в знаках после десятичной запятой;
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- если Digits положительное, то округление
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в знаках до запятой *)
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PROCEDURE SimpleRoundTo* (AValue: REAL; Digits: INTEGER): REAL;
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VAR
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RV, a : REAL;
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BEGIN
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RV := Math.ipower(10.0, -Digits);
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IF AValue < 0.0 THEN
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a := trunc((AValue * RV) - 0.5)
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ELSE
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a := trunc((AValue * RV) + 0.5)
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END
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RETURN a / RV
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END SimpleRoundTo;
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END MathRound.
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