Casio fx-4000P
Datasheet legend
Ab/c:
Fractions calculation
AC: Alternating current BaseN: Number base calculations Card: Magnetic card storage Cmem: Continuous memory Cond: Conditional execution Const: Scientific constants Cplx: Complex number arithmetic DC: Direct current Eqlib: Equation library Exp: Exponential/logarithmic functions Fin: Financial functions Grph: Graphing capability Hyp: Hyperbolic functions Ind: Indirect addressing Intg: Numerical integration Jump: Unconditional jump (GOTO) Lbl: Program labels LCD: Liquid Crystal Display LED: Light-Emitting Diode Li-ion: Lithium-ion rechargeable battery Lreg: Linear regression (2-variable statistics) mA: Milliamperes of current Mtrx: Matrix support NiCd: Nickel-Cadmium rechargeable battery NiMH: Nickel-metal-hydrite rechargeable battery Prnt: Printer RTC: Real-time clock Sdev: Standard deviation (1-variable statistics) Solv: Equation solver Subr: Subroutine call capability Symb: Symbolic computing Tape: Magnetic tape storage Trig: Trigonometric functions Units: Unit conversions VAC: Volts AC VDC: Volts DC |
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Casio fx-4000P
After initially offering such marvellous calculators as the fx-201P or the FX-602P, Casio went steadily downhill; most of their later programmable models have extremely limited programmability, both in terms of capacity and in terms of functionality.
Not so the fx-4000P. This is a no-compromise, high-end, classic programmable. With a full set of scientific functions and a whopping 550-step program memory, this is definitely a serious engineering tool. They just don't make machines like this anymore!
I first came across the fx-4000P in its OEM guise as the Radio Shack EC-4020. At the time, I did not yet know about the fx-4000P model number, so the find represented a bit of a mystery.
In 2012, some 13 years after I received my first EC-4020 and 11 years after I came across the first fx-4000P, a kind calculator owner, Aron from NJ sent me his old fx-4000P, this time with an English manual. At last! (Well, I did have a German manual and the English manual for the EC-4020, but it's not quite like the real thing.) I must say, it is still a lovely, very capable machine; my only two complaints are the somewhat hard to read display and a less than ideally robust construction.
The program below, intended to demonstrate the fx-4000P's programming model, uses the Lanczos-approximation to accurately compute the logarithm of the Gamma function. A conditional expression is used to compute the correct result for negative arguments (the machine must be in radians mode; also note the difference between minus signs, '-', and subtraction signs, '−'):
Ans→X: Abs X→Z: ln (2.506628275+6.3E-10+(225.5255846+1.9E-8)÷Z− (268.2959738+4.1E-8)÷(Z+1)+(80.90308069+3.5E-9)÷(Z+2)− (5.007578639+7.1E-10)÷(Z+3)+(1.146848954E-2+3.5E-12)÷(Z+4))+ (Z−.5)ln (Z+4.65)−Z−4.65→G: X<0⇒ln (-π÷X÷sin πX)−G→G:G