Check in the pristine copy of ICU 4.6...

icu46/source/test/perf/perldriver/Format.pm

+#!/usr/local/bin/perl
+#  ********************************************************************
+#  * COPYRIGHT:
+#  * Copyright (c) 2002, International Business Machines Corporation and
+#  * others. All Rights Reserved.
+#  ********************************************************************
+
+my $PLUS_MINUS = "±";
+
+#|#---------------------------------------------------------------------
+#|# Format a confidence interval, as given by a Dataset.  Output is as
+#|# as follows:
+#|#   241.23 - 241.98 => 241.5 +/- 0.3
+#|#   241.2 - 243.8 => 242 +/- 1
+#|#   211.0 - 241.0 => 226 +/- 15 or? 230 +/- 20
+#|#   220.3 - 234.3 => 227 +/- 7
+#|#   220.3 - 300.3 => 260 +/- 40
+#|#   220.3 - 1000 => 610 +/- 390 or? 600 +/- 400
+#|#   0.022 - 0.024 => 0.023 +/- 0.001
+#|#   0.022 - 0.032 => 0.027 +/- 0.005
+#|#   0.022 - 1.000 => 0.5 +/- 0.5
+#|# In other words, take one significant digit of the error value and
+#|# display the mean to the same precision.
+#|sub formatDataset {
+#|    my $ds = shift;
+#|    my $lower = $ds->getMean() - $ds->getError();
+#|    my $upper = $ds->getMean() + $ds->getError();
+#|    my $scale = 0;
+#|    # Find how many initial digits are the same
+#|    while ($lower < 1 ||
+#|           int($lower) == int($upper)) {
+#|        $lower *= 10;
+#|        $upper *= 10;
+#|        $scale++;
+#|    }
+#|    while ($lower >= 10 &&
+#|           int($lower) == int($upper)) {
+#|        $lower /= 10;
+#|        $upper /= 10;
+#|        $scale--;
+#|    }
+#|}
+
+#---------------------------------------------------------------------
+# Format a number, optionally with a +/- delta, to n significant
+# digits.
+#
+# @param significant digit, a value >= 1
+# @param multiplier
+# @param time in seconds to be formatted
+# @optional delta in seconds
+#
+# @return string of the form "23" or "23 +/- 10".
+#
+sub formatNumber {
+    my $sigdig = shift;
+    my $mult = shift;
+    my $a = shift;
+    my $delta = shift; # may be undef
+    
+    my $result = formatSigDig($sigdig, $a*$mult);
+    if (defined($delta)) {
+        my $d = formatSigDig($sigdig, $delta*$mult);
+        # restrict PRECISION of delta to that of main number
+        if ($result =~ /\.(\d+)/) {
+            # TODO make this work for values with all significant
+            # digits to the left of the decimal, e.g., 1234000.
+
+            # TODO the other thing wrong with this is that it
+            # isn't rounding the $delta properly.  Have to put
+            # this logic into formatSigDig().
+            my $x = length($1);
+            $d =~ s/\.(\d{$x})\d+/.$1/;
+        }
+        $result .= " $PLUS_MINUS " . $d;
+    }
+    $result;
+}
+
+#---------------------------------------------------------------------
+# Format a time, optionally with a +/- delta, to n significant
+# digits.
+#
+# @param significant digit, a value >= 1
+# @param time in seconds to be formatted
+# @optional delta in seconds
+#
+# @return string of the form "23 ms" or "23 +/- 10 ms".
+#
+sub formatSeconds {
+    my $sigdig = shift;
+    my $a = shift;
+    my $delta = shift; # may be undef
+
+    my @MULT = (1   , 1e3,  1e6,  1e9);
+    my @SUFF = ('s' , 'ms', 'us', 'ns');
+
+    # Determine our scale
+    my $i = 0;
+    #always do seconds if the following line is commented out
+    ++$i while ($a*$MULT[$i] < 1 && $i < @MULT);
+    
+    formatNumber($sigdig, $MULT[$i], $a, $delta) . ' ' . $SUFF[$i];
+}
+
+#---------------------------------------------------------------------
+# Format a percentage, optionally with a +/- delta, to n significant
+# digits.
+#
+# @param significant digit, a value >= 1
+# @param value to be formatted, as a fraction, e.g. 0.5 for 50%
+# @optional delta, as a fraction
+#
+# @return string of the form "23 %" or "23 +/- 10 %".
+#
+sub formatPercent {
+    my $sigdig = shift;
+    my $a = shift;
+    my $delta = shift; # may be undef
+    
+    formatNumber($sigdig, 100, $a, $delta) . '%';
+}
+
+#---------------------------------------------------------------------
+# Format a number to n significant digits without using exponential
+# notation.
+#
+# @param significant digit, a value >= 1
+# @param number to be formatted
+#
+# @return string of the form "1234" "12.34" or "0.001234".  If
+#         number was negative, prefixed by '-'.
+#
+sub formatSigDig {
+    my $n = shift() - 1;
+    my $a = shift;
+
+    local $_ = sprintf("%.${n}e", $a);
+    my $sign = (s/^-//) ? '-' : '';
+
+    my $a_e;
+    my $result;
+    if (/^(\d)\.(\d+)e([-+]\d+)$/) {
+        my ($d, $dn, $e) = ($1, $2, $3);
+        $a_e = $e;
+        $d .= $dn;
+        $e++;
+        $d .= '0' while ($e > length($d));
+        while ($e < 1) {
+            $e++;
+            $d = '0' . $d;
+        }
+        if ($e == length($d)) {
+            $result = $sign . $d;
+        } else {
+            $result = $sign . substr($d, 0, $e) . '.' . substr($d, $e);
+        }
+    } else {
+        die "Can't parse $_";
+    }
+    $result;
+}
+
+1;
+
+#eof