TI-74 and Python (Casio fx-9750GIII): A Treasure of Programs
Today's programs illustrates an approach from both the BASIC and Python programming languages.
Skiing Stars
This program paves a ski path by randomly plotting a path. A slight difference: the TI-74 version goes indefinitely until the user presses a key and uses one line. The Python version goes 50 steps and the result must be scrolled up after the program completes. I optimized the program to fit each screen.
TI-74 BASICALC Program
100 REM "Skiing Stars"
102 RANDOMIZE RND
104 P=14
106 PRINT "Press any key to stop.": PAUSE .25
120 CALL KEY(K,S)
122 IF S<>0 THEN 140
124 R=RND
126 IF R<.4 AND P>0 THEN LET P=P-1
128 IF R>.4 AND P<26 THEN LET P=P+1
130 DISPLAY ERASE ALL AT(P),"*****": PAUSE .15
132 GOTO 120
140 PRINT RPT$("*",31): PAUSE .25
142 STOP
Python (Casio fx-9750GIII): skistar.py
# skiing stars
from random import *
rnd=int(10000000*random())
seed(rnd)
p=8
for i in range(50):
r=random()
if r<.4 and p>0:
p-=1
if r>.6 and p<14:
p+=1
print(" "*p+"*****")
print("scroll up")
Phase Speed of a Wave
Equation:
c = √( g * λ / (2 * π) * tanh(2 * π * d / λ))
c = phase speed
λ = wavelength
d = water depth
g = Earth's gravity = 9.80665 m/s = 32.174049 ft/s
Source:
"Wind Wave" Wikipedia. Last Edited January 28, 2023. Accessed February 14, 2023. https://en.wikipedia.org/wiki/Wind_wave#:~:text=In%20fluid%20dynamics%2C%20a%20wind,is%20known%20as%20the%20fetch.
TI-74 BASICALC Program:
400 REM Phase Speed
402 PRINT "U.S. units used": PAUSE .25
404 T=2*PI: G=32.174049
406 INPUT "Depth (ft)? "; D
408 INPUT "Wavelength (ft)? "; L
410 C=SQR(G*L/T*TANH(T*D/L))
412 PRINT "Phase Speed (ft/s)=": PAUSE .25
414 PRINT C: PAUSE
416 STOP
Python (Casio fx-9750GIII): phspeed.py
# phase speed
from math import *
print("U.S units used")
t=2*pi
g=32.174049
print("Depth (ft)?")
d=float(input())
print("Wavelength?")
l=float(input())
c=sqrt(g*l/t*tanh(t*d/l))
print("Phase speed (ft/s)=")
print(c)
Example:
Depth: 2.26 ft
Wavelength: 18.9 ft
Result:
Phase Speed: 7.845145563 ft/s
Horsepower Generated by a Wave
p = 0.0329 * h^2 * √( l * (1 - 4.935 * (h^2/l^2))
h = wave height (ft)
l = length of a wave (ft)
p = horsepower
Source:
Rosenstein, Morton. Strategies for Scientific Calculating Casio. January 1982.
TI-74 BASICALC Program:
500 REM horsepower of a wave
502 PRINT "U.S. units used": PAUSE .25
504 INPUT "Wave height (ft)? ";H
506 INPUT "Length of wave (ft)? "; L
508 P=.0329*H^2*SQR(L*(1-4.935*(H^2/L^2)))
510 PRINT "Horsepower = ": PAUSE .25
512 PRINT P: PAUSE
514 STOP
Python (Casio fx-9750GIII): hpwave.py
# horsepower of a wave
from math import *
print("U.S. units used")
print("Wave height (ft)?")
h=float(input())
print("Length of a wave?")
l=float(input())
p=.0329*h**2*sqrt(l*(1-4.935*(h**2/l**2)))
print("horsepower = ")
print(p)
Example:
Wave height: 1.26 ft
Length of wave: 24.04 ft
Result:
Horsepower = .2543549811 hp
Until next time,
Eddie
All original content copyright, © 2011-2023. Edward Shore. Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited. This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.
