--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc.py	Fri Sep 27 16:50:42 2024 +0930
@@ -0,0 +1,40 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2024
+#      Daniel O'Connor <darius@dons.net.au>.  All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+
+def sifmt(_v, dp = 3, unit = 'Hz', sp = ' '):
+    '''Format a number using SI prefixes'''
+    si_prefixes = ('T', 'G', 'M', 'k', '', 'm', 'µ', 'n', 'p')
+    scale = 10 ** 12
+    v = abs(_v)
+    if v == 0:
+        sip = ""
+        scale = 0
+    for i, sip in enumerate(si_prefixes):
+        if v >= scale:
+            break
+        scale /= 1e3
+    return ('%.' + str(dp) + 'f%s%s%s') % (_v / scale, sp, si_prefixes[i], unit)