Showing posts with label Casio Classpad fx-CP400. Show all posts
Showing posts with label Casio Classpad fx-CP400. Show all posts

Thursday, June 16, 2016

Casio Classpad Functions: Coordinate, Bearing, Slope, Triangle Area, Electric Oscillation, RLC Impedance

Casio Classpad Functions:  Coordinate, Bearing, Slope, Triangle Area,  Electric Oscillation, RLC Impedance 


Nothing like doing some programming while on vacation. :)

Civil Engineering/Geometry:  tcoordin, bearing, cslope, aritri

For the following, enter coordinates in complex number format:  (east coordinate) + (north coordinate)*I  (x + y*i).  For example, enter the coordinate (3, 6) as 3+6i.

Coordinate Calculation - tcoordin



Inputs:  pt, len, ang
pt = point 0, enter as a complex number
len = length of travel
ang = bearing angle (treated as degrees)

Output:
Point 1 (as a complex number)

Function:
approx(pt+compToRect(∠(len,ang°)))

Example:
tcoordin(4 + 5*i, 24.2, -10) returns 27.83234762+0.7977141005*i

Bearing Angle (from East) – bearing

Inputs: pt1, pt2
pt1 = point 1, enter as a complex number (start)
pt2 = point 2, enter as a complex number (end)

Output:
A list of two elements:  length, bearing from point 1 (depending on setting)

Function:
approx({abs(pt2-pt1),arg(pt2-pt1)})

Example:
bearing(-2.2+3i, 4+2i) returns {6.280127387, -9.162347046} (degree mode)

Slope Between two Points (extra) – cslope

Inputs: pt1, pt2
pt1 = point 1, enter as a complex number (start)
pt2 = point 2, enter as a complex number (end)

Output:  Slope from point 1 to point 2.

Function:
approx(im(pt2-pt1)/re(pt2-pt1))

Example:
cslope( 7+7i, 2+16i ) returns -1.8

Area of a Triangle knowing the Vertex Points – aritri



Inputs: pt1, pt2, pt3
pt1 = point 1, enter as a complex number
pt2 = point 2, enter as a complex number
pt3 = point 3, enter as a complex number

Output:  area of the triangle

Function:
approx(abs(.5*(re(p1-p2)*im(p3-p1)+re(p1-p3)*im(p1-p2))))

Example:
aritri(0, 4+7i, 2+5i) returns 3
0 = 0 + 0i


Electrical Functions:  rlcserim, rlcparim, freqosc

Functions for RLC posted are now corrected - EWS 6/26/2016

Impedance of an RLC Series Circuit:  rlcserim



Inputs:
r = resistance (in Ohms)
c = capacitance (in Farads)
l = inductance (in Henrys)
f = frequency (in Hertz)

Output:
z = impedance (in Ohms)

Function:
approx(√(r^2+(2*π*f*l-1/(2*π*f*c))^2))

Example:
rlcserim(10, 500E-6, 2E-3, 2000) returns 26.90130131 ohms

Impedance of an RLC Parallel Circuit:  rlcparim
  
Inputs:
r = resistance (in Ohms)
c = capacitance (in Farads)
l = inductance (in Henrys)
f = frequency (in Hertz)

Output:
z = impedance (in Ohms)

Function:
approx(1/√((1/r)^2+(2*π*f*c-1/(2*π*f*l))^2))

Example:

rlcparim(40, 550E-6, 2E-3, 1000) returns 0.2961851056

Frequency of Electric Oscillation – freqosc

Inputs:
l = coil self-inductance (in Henrys)
c = capacitance (in Farads)

Output:
f = frequency (in Hertz)

Function:
approx(1/(2*π*√(l*c)))

Example:
freqosc(550E-6, 2E-3) returns 151.7482841

Sources:

Casio.  “fx-FD10 Pro User’s Guide” and “fx-50F Plus User’s Guide”.  2014 and 2006, respectively

This blog is property of Edward Shore, 2016.



Casio Classpad’s (fx-CP400) Hidden Shift Functions

fx-CP400 Keyboard



Hidden Shift Functions

When I was giving a quick review of the Classpad’s fx-CP400 last March (http://edspi31415.blogspot.com/2016/03/a-quick-look-at-casio-classpad-fx-cp400.html), I mentioned that I would have liked the basic scientific functions assigned and listed on the keyboard.  It turns out that most of the keys have shifted functions.  The reason why they are not listed is because the shifted functions can be customized.  Here are the default shift settings:

COPY
CUT
PASTE
UNDO
√[ ]  
[ ] / [ ]
=
x
y
z
^
÷
T




(
7
8
9
*
θ
e^[ ]
ln(
log[ ]

)
4
5
6
-
|  with
sin(
cos(
tan(

,
1
2
3
+
=> store
π
i
ans
(-)
0
.
EXP
EXE

To assign (or clear) keyboard assignments: 
1.  Press Menu
2.  Select System (2nd page)
3.  On the top row of icons, select the (Shift) icon.  (first set, farthest right)
4.  Select a key.  To assign a function, select the box next to [ Set ].  Call up the keyboard if needed.  When are you ready, press [ Set ].
5.  You can clear a key by pressing [ Clear ].
6. To return to default settings, press [ Default ].
7.  When you are done with the keyboard settings, press [ OK ]. 
8.  Test your settings by going to the Main screen.

This is also shown on pg. 247 of the Casio Classpad II manual.

Here is my customized keyboard.  I made a keyboard on an index card and keep it with the Classpad.  It is great because we can easily call up commonly used functions without having to hunt through the soft keyboard.  For mine, I just kept the defaults and added some other basics to the missing keys (they are in green for reference):

COPY
CUT
PASTE
UNDO
√[ ]  
[ ] / [ ]
=
x
y
z
^
÷
t
sinˉ¹(
cosˉ¹(
tanˉ¹(
{ }
(
7
8
9
*
θ
e^[ ]
ln(
log[ ]
abs(
)
4
5
6
-
|  with
sin(
cos(
tan(
arg(
,
1
2
3
+
=> store
π
i
ans
(-)
0
.
EXP
EXE



This blog is property of Edward Shore, 2016.

Sunday, May 15, 2016

Fraction Approximation on Graphing Calculators Comparisons

Fraction Approximation on Graphing Calculators Comparisons

 Advanced calculators and calculator apps sometimes give the ability for the user to convert answers to fractions.  For rational numbers, the fractional conversions are precise and easy.  However, for irrational numbers, different calculators use different algorithms.  I am going to use three calculators to compare fractional answers:

TI-Nspire CAS iOS App:  Fractional Approximations

* TI-NSpire CAS iOS App:  this should be similar to the TI-Nspire CAS handheld calculators, x→approxFraction(5.E-14)

* Casio Classpad fx-CP400:  fractional approximation used by tofrac(approx(x))

* HP Prime (firmware 10077), pressing [a b/c] after the number is entered

Square Root of 2, √2
Decimal Approximation
1.41421356237
TI-NSpire CAS
3,880,899/2,744,210
Casio Classpad fx-CP400
13,250,218/9,369,319
HP Prime
114,243/80,782

Square Root of 3, √3
Approximation
1.73205080757
TI-NSpire CAS
3,650,401/2,107,560
Casio Classpad fx-CP400
3,650,401/2,107,560
HP Prime
191,861/110,771

Square Root of 5, √5
Approximation
2.2360679775
TI-NSpire CAS
3,940,598/1,762,289
Casio Classpad fx-CP400
16,692,641/7,465,176
HP Prime
219,602/98,209

Euler’s Number, e
Approximation
2.71828182846
TI-NSpire CAS
14,665,106/5,394,991
Casio Classpad fx-CP400
14,665,106/5,394,991
HP Prime
219,602/98,209

The Constant Pi, π
Approximation
3.14159265359
TI-NSpire CAS
5,149,351/1,725,033
Casio Classpad fx-CP400
69,305,155/22,060,516
HP Prime
312,689/99,532

The Constant Pi, π^2
Approximation
9.86960440109
TI-NSpire CAS
26,140,802/2,648,617
Casio Classpad fx-CP400
26,140,802/2,648,617
HP Prime
12,59,401/127,604

The Golden Ratio, Φ = (1 + √5)/2
Approximation
1.61803398875
TI-NSpire CAS
5,702,887/3,524,578
Casio Classpad fx-CP400
5,702,887/3,524,578
HP Prime
121,393/75,025

The Zeta of 3, ζ(3) ≈ 1.20205693015959428539
Approximation
1.20205690316
TI-NSpire CAS
2,721,755/2,264,248
Casio Classpad fx-CP400
2,721,755/2,264,248
HP Prime
927,328/771,451


This blog is property of Edward Shore, 2016

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