Threaded Mode | Linear Mode

Dave Britten · (This post was last modified: 07-05-2018 09:32 PM by Dave Britten.)

A simple program for sorting a matrix by your choice of column, in either ascending or descending order.

Usage

Arguments:

y: Matrix
x: Column number (1-based)

Flag 1: Clear = Ascending Order, Set = Descending Order

Put the arguments on the stack and XEQ "SORT". The sorted matrix will be left on the stack in x. Attempting to sort a 1-row matrix will exit cleanly without doing anything.

EDIT: A nicer version that uses the built-in (hidden) "[MIN]" and "[MAX]" functions to do selection sort. When keying this in, note that the brackets are part of the function name and must be included! I've written that function as XEQ "[MIN]" for clarity, but you'll only see [MIN] after entering the command. Thanks Joe.

Code:

LBL "SORT"

RDown

STO "_D"

RDown

STO "_Z"

RDown

STO "_T"

RDown

INDEX "_D"

1

X<>Y

STOIJ

LBL 00

RCLIJ

X<>Y

FC? 01

XEQ "[MIN]"

FS? 01

XEQ "[MAX]"

RDown

R<>R

I+

FC? 76

GTO 00

RCL "_T"

ENTER

ENTER

RCL "_Z"

RCL "_D"

CLV "_M"

CLV "_R"

CLV "_D"

CLV "_Z"

CLV "_T"

END