HP 42S/Free 42S/DM42: Dynamic Growing Lists
Introduction
This blog entry will show how to create dynamic matrices that grow as additional entries are necessary.
DIM: (Syntax: rows, cols, DIM) Sets the initial dimensions of the matrix.
INDEX: Sets the index pointer to I = 1 and J = 1.
GROW: Sets the HP 42S to grow mode. This allows the matrix to build additional rows and columns by adding new elements.
J+: Does one of two things in Grow Mode. It either moves the pointer to the next column or creates a new row. For a matrix with only 1 column as its initial dimension, J+ creates a new row automatically.
Matrix: 1 to N
The first program, nLIST generates a one column matrix from 1 to n.
LBL 00: Main Loop
LBL 01: Adds another row
LBL 02: End of program and shows the resulting matrix, MATD in edit mode
R01: counter variable counting from n (in X stack) to 1
HP 42S/Free 42S/DM42 Program: nLIST
00 { 50-Byte Prgm }
01▸LBL "nLIST"
02 STO 01
03 1
04 1
05 DIM "MATD"
06 INDEX "MATD"
07 GROW
08▸LBL 00
09 RCL 01
10 STOEL
11 DSE 01
12 GTO 01
13 GTO 02
14▸LBL 01
15 J+
16 GTO 00
17▸LBL 02
18 EDITN "MATD"
19 END
Example: 8 nLIST returns
[[ 8 ]
[ 7 ]
[ 6 ]
[ 5 ]
[ 4 ]
[ 3 ]
[ 2 ]
[ 1 ]]
Press the soft keys ( ↑ ) and ( ↓ ) to scroll throw the matrix. Press [EXIT] to exit the matrix. The matrix MATD is stored as a stack element.
Simulating HP Prime's idivis Command
The program IDIVIS simulates the IDIVIS command on the HP Prime. IDIVIS lists all the divisors of an integer ( n ).
LBL 00: Main Loop - tests for divisors
LBL 01: Adds any divisors and creates another row
LBL 02: Decreases the counter variable
LBL 03: Trims the excessive row by the DELR (delete row) command, ends the program and shows the resulting matrix, MATD in edit mode
R00: n
R01: counter variable counting from n (in X stack) to 1. The program stops when R01 reaches 0 (it is skipped thanks to the DSE command).
R02 = R00/R01
HP 42S/Free 42S/DM42S Program: IDIVIS
00 { 64-Byte Prgm }
01▸LBL "IDIVIS"
02 STO 00
03 STO 01
04 1
05 1
06 DIM "MATD"
07 INDEX "MATD"
08 GROW
09▸LBL 00
10 RCL 00
11 RCL÷ 01
12 STO 02
13 FP
14 X=0?
15 GTO 01
16 GTO 02
17▸LBL 01
18 RCL 02
19 STOEL
20 J+
21▸LBL 02
22 DSE 01
23 GTO 00
24 GTO 03
25▸LBL 03
26 DELR
27 EDITN "MATD"
28 .END.
Examples
45 (IDIVIS) returns 1, 3, 5, 9, 15, 45 (press ↓ to reveal the next row in MATD)
27 (IDIVIS) returns 1, 3, 9, 27
53 (IDIVIS) returns 1, 53
Eddie
All original content copyright, © 2011-2020. 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.
Introduction
This blog entry will show how to create dynamic matrices that grow as additional entries are necessary.
DIM: (Syntax: rows, cols, DIM) Sets the initial dimensions of the matrix.
INDEX: Sets the index pointer to I = 1 and J = 1.
GROW: Sets the HP 42S to grow mode. This allows the matrix to build additional rows and columns by adding new elements.
J+: Does one of two things in Grow Mode. It either moves the pointer to the next column or creates a new row. For a matrix with only 1 column as its initial dimension, J+ creates a new row automatically.
Matrix: 1 to N
The first program, nLIST generates a one column matrix from 1 to n.
LBL 00: Main Loop
LBL 01: Adds another row
LBL 02: End of program and shows the resulting matrix, MATD in edit mode
R01: counter variable counting from n (in X stack) to 1
HP 42S/Free 42S/DM42 Program: nLIST
00 { 50-Byte Prgm }
01▸LBL "nLIST"
02 STO 01
03 1
04 1
05 DIM "MATD"
06 INDEX "MATD"
07 GROW
08▸LBL 00
09 RCL 01
10 STOEL
11 DSE 01
12 GTO 01
13 GTO 02
14▸LBL 01
15 J+
16 GTO 00
17▸LBL 02
18 EDITN "MATD"
19 END
Example: 8 nLIST returns
[[ 8 ]
[ 7 ]
[ 6 ]
[ 5 ]
[ 4 ]
[ 3 ]
[ 2 ]
[ 1 ]]
Press the soft keys ( ↑ ) and ( ↓ ) to scroll throw the matrix. Press [EXIT] to exit the matrix. The matrix MATD is stored as a stack element.
Simulating HP Prime's idivis Command
The program IDIVIS simulates the IDIVIS command on the HP Prime. IDIVIS lists all the divisors of an integer ( n ).
LBL 00: Main Loop - tests for divisors
LBL 01: Adds any divisors and creates another row
LBL 02: Decreases the counter variable
LBL 03: Trims the excessive row by the DELR (delete row) command, ends the program and shows the resulting matrix, MATD in edit mode
R00: n
R01: counter variable counting from n (in X stack) to 1. The program stops when R01 reaches 0 (it is skipped thanks to the DSE command).
R02 = R00/R01
HP 42S/Free 42S/DM42S Program: IDIVIS
00 { 64-Byte Prgm }
01▸LBL "IDIVIS"
02 STO 00
03 STO 01
04 1
05 1
06 DIM "MATD"
07 INDEX "MATD"
08 GROW
09▸LBL 00
10 RCL 00
11 RCL÷ 01
12 STO 02
13 FP
14 X=0?
15 GTO 01
16 GTO 02
17▸LBL 01
18 RCL 02
19 STOEL
20 J+
21▸LBL 02
22 DSE 01
23 GTO 00
24 GTO 03
25▸LBL 03
26 DELR
27 EDITN "MATD"
28 .END.
Examples
45 (IDIVIS) returns 1, 3, 5, 9, 15, 45 (press ↓ to reveal the next row in MATD)
27 (IDIVIS) returns 1, 3, 9, 27
53 (IDIVIS) returns 1, 53
Eddie
All original content copyright, © 2011-2020. 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.