Thursday, January 14, 2016

HP 15C: Stair Calculations



HP 15C:  Stair Calculations

Variables:

Input: 
R0 = Riser Height (RH)
R1 = Run
R2 = Rise

Store values in R0, R1, and R2 before running the program.

Output:
R3 = number of stairs (S)
R4 = Treadwidth (TW)
R5 = Stringer Length (ST)

Formulas Used:

S = int(rise/RH) – 1
TW = run/S
ST = S * √(RH^2 + TW^2)

Step
Key
Key Code
001
LBL C
42, 21, 13
002
RCL 2
45, 2
003
RCL÷ 0
45, 10, 0
004
INT
43, 44
005
1
1
006
-
30
007
STO 3
44, 3
008
R/S (S)
31
009
1/X
37
010
RCL* 1
45, 20 ,1
011
STO 4
44, 4
012
R/S  (TW)
31
013
X^2
43, 11
014
RCL 0
45, 0
015
X^2
43, 11
016
+
40
017
11
018
RCL* 3
45, 20, 3
019
STO 5
44, 5
020
RTN
43, 32

Example:

R0 = 7 inches (riser height)
R1 = 56 inches (run)
R2 = 80 inches (rise)

Results:

R3 = 10 (number of stairs)
R4 = 5.6 inches (treadwidth)
R5 ≈ 89.6437 inches (stringer)

This blog is property of Edward Shore.  2016


Sum of Sequential Integers (featuring Swiss Micros DM32)

  Sum of Sequential Integers ( featuring Swiss Micros DM32) What is the sum of the following: 100 + 101 + 102 + 103 + 104 + 105 + … + ...