From dd98bfe5ce035bb7ff07a6bd4a704b52c88e88b8 Mon Sep 17 00:00:00 2001
From: Cody Boone Ferguson <53008573+xexyl@users.noreply.github.com>
Date: Thu, 7 Dec 2023 05:55:45 -0800
Subject: [PATCH] Improve how to set number of arrows 1994/dodsond2

Using a Makefile variable one can now do

    make clobber ARROWS=5 alt

or whatever they wish to set it to. The code already checked the range.
---
 1994/dodsond2/Makefile  | 7 +++++--
 1994/dodsond2/README.md | 2 +-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/1994/dodsond2/Makefile b/1994/dodsond2/Makefile
index d93a70cab..2c276590a 100644
--- a/1994/dodsond2/Makefile
+++ b/1994/dodsond2/Makefile
@@ -58,7 +58,7 @@ ARCH=
 
 # Defines that are needed to compile
 #
-CDEFINE= -DW=3
+CDEFINE= -DW=${ARROWS}
 
 # Include files that are needed to compile
 #
@@ -138,8 +138,11 @@ ${PROG}: ${PROG}.c
 alt: data ${ALT_TARGET}
 	@${TRUE}
 
+# variable to allow overriding how many arrows to start with
+ARROWS= 3
+
 ${PROG}.alt: ${PROG}.alt.c
-	${CC} ${CFLAGS} $< -o $@ ${LDFLAGS}
+	${CC} ${CFLAGS} -DW=${ARROWS} $< -o $@ ${LDFLAGS}
 
 # data files
 #
diff --git a/1994/dodsond2/README.md b/1994/dodsond2/README.md
index 5c86b55e4..dcfd713d2 100644
--- a/1994/dodsond2/README.md
+++ b/1994/dodsond2/README.md
@@ -46,7 +46,7 @@ The default number of arrows in this version is 3 but if you want to change it,
 say to 5, try:
 
 ```sh
-make clobber CDEFINE="-DW=5" alt
+make clobber ARROWS=5 alt
 ```