QBasic/Advanced Maths

Complex mathematical functions There are a few trigonometrical operations in QBasic such as: A = 90 PRINT SIN(A) PRINT COS(A) PRINT TAN(A) PRINT ATN(A) 'not trigonometrical PRINT LOG(A) Most of the other complex calculations do not have appropriate functions in QBasic and hence you have to use functions and make them yourselves. FUNCTION SEC (x) 'Secant IF COS(x) <> 0 THEN SEC = 1 / COS(x) ELSE BEEP END FUNCTION FUNCTION CSC (x) 'CoSecant IF SIN(x) <> 0 THEN CSC = 1 / SIN(x) ELSE BEEP END FUNCTION FUNCTION COT (x) 'CoTangent IF TAN(x) <> 0 THEN COT = 1 / TAN(x) ELSE BEEP END FUNCTION FUNCTION ARCSIN (x) 'Inverse Sine IF x < 1 THEN ARCSIN = ATN(x / SQR(1 - (x * x))) ELSE BEEP END FUNCTION FUNCTION ARCCOS (x) ' Inverse Cosine IF x < 1 THEN ARCCOS = (2 * ATN(1)) - ATN(x / SQR(1 - x * x)) ELSE BEEP END FUNCTION FUNCTION ARCSEC (x) ' Inverse Secant IF x < 1 THEN ARCSEC = ATN(x / SQR(1 - x * x)) + (SGN(x) - 1) * (2 * ATN(1)) ELSE BEEP END FUNCTION FUNCTION ARCCSC (x) ' Inverse CoSecant IF x < 1 THEN ARCCSC = ATN(1 / SQR(1 - x * x)) + (SGN(x)-1) * (2 * ATN(1)) ELSE BEEP END FUNCTION FUNCTION ARCCOT (x) ' Inverse CoTangent ARCCOT = (2 * ATN(1)) - ATN(x) END FUNCTION FUNCTION SINH (x) ' Hyperbolic Sine IF x <= 88.02969 THEN SINH = (EXP(x) - EXP(-x)) / 2 ELSE BEEP END FUNCTION FUNCTION COSH (x) ' Hyperbolic CoSine IF x <= 88.02969 THEN COSH = (EXP(x) + EXP(-x)) / 2 ELSE BEEP END FUNCTION FUNCTION TANH (x) ' Hyperbolic Tangent or SINH(x) / COSH(x) IF 2 * x <= 88.02969 AND EXP(2 * x) + 1 <> 0 THEN TANH = (EXP(2 * x) - 1) / (EXP(2 * x) + 1) ELSE BEEP END IF END FUNCTION FUNCTION SECH (x) ' Hyperbolic Secant or (COSH(x)) ^ -1 IF x <= 88.02969 AND (EXP(x) + EXP(-x)) <> 0 THEN SECH = 2 / (EXP(x) + EXP(-x)) ELSE BEEP END FUNCTION FUNCTION CSCH (x) ' Hyperbolic CoSecant or (SINH(x)) ^ -1 IF x <= 88.02969 AND (EXP(x) - EXP(-x)) <> 0 THEN CSCH = 2 / (EXP(x) - EXP(-x)) ELSE BEEP END FUNCTION FUNCTION COTH (x) ' Hyperbolic CoTangent or COSH(x) / SINH(x) IF 2 * x <= 88.02969 AND EXP(2 * x) - 1 <> 0 THEN COTH = (EXP(2 * x) + 1) / (EXP(2 * x) - 1) ELSE BEEP END IF END FUNCTION FUNCTION ARCSINH (x) ' Inverse Hyperbolic Sine IF (x * x) + 1 >= 0 AND x + SQR((x * x) + 1) > 0 THEN ARCSINH = LOG(x + SQR(x * x + 1)) ELSE BEEP END IF END FUNCTION FUNCTION ARCCOSH (x) ' Inverse Hyperbolic CoSine IF x >= 1 AND x * x - 1 >= 0 AND x + SQR(x * x - 1) > 0 THEN ARCCOSH = LOG(x + SQR(x * x - 1)) ELSE BEEP END IF END FUNCTION FUNCTION ARCTANH (x) ' Inverse Hyperbolic Tangent IF x < 1 THEN ARCTANH = LOG((1 + x) / (1 - x)) / 2 ELSE BEEP END FUNCTION FUNCTION ARCSECH (x) ' Inverse Hyperbolic Secant IF x > 0 AND x <= 1 THEN ARCSECH = LOG((SGN(x) * SQR(1 - x * x) + 1) / x) ELSE BEEP END FUNCTION FUNCTION ARCCSCH (x) ' Inverse Hyperbolic CoSecant IF x <> 0 AND x * x + 1 >= 0 AND (SGN(x) * SQR(x * x + 1) + 1) / x > 0 THEN ARCCSCH = LOG((SGN(x) * SQR(x * x + 1) + 1) / x) ELSE BEEP END IF END FUNCTION FUNCTION ARCCOTH (x) ' Inverse Hyperbolic CoTangent IF x > 1 THEN ARCCOTH = LOG((x + 1) / (x - 1)) / 2 ELSE BEEP END FUNCTION Some examples taken from the QB64 IDE help page.