1#!/usr/local/bin/perl 2# ******************************************************************** 3# * COPYRIGHT: 4# * © 2016 and later: Unicode, Inc. and others. 5# * License & terms of use: http://www.unicode.org/copyright.html 6# * Copyright (c) 2006, International Business Machines Corporation and 7# * others. All Rights Reserved. 8# ******************************************************************** 9 10my $PLUS_MINUS = "±"; 11 12#|#--------------------------------------------------------------------- 13#|# Format a confidence interval, as given by a Dataset. Output is as 14#|# as follows: 15#|# 241.23 - 241.98 => 241.5 +/- 0.3 16#|# 241.2 - 243.8 => 242 +/- 1 17#|# 211.0 - 241.0 => 226 +/- 15 or? 230 +/- 20 18#|# 220.3 - 234.3 => 227 +/- 7 19#|# 220.3 - 300.3 => 260 +/- 40 20#|# 220.3 - 1000 => 610 +/- 390 or? 600 +/- 400 21#|# 0.022 - 0.024 => 0.023 +/- 0.001 22#|# 0.022 - 0.032 => 0.027 +/- 0.005 23#|# 0.022 - 1.000 => 0.5 +/- 0.5 24#|# In other words, take one significant digit of the error value and 25#|# display the mean to the same precision. 26#|sub formatDataset { 27#| my $ds = shift; 28#| my $lower = $ds->getMean() - $ds->getError(); 29#| my $upper = $ds->getMean() + $ds->getError(); 30#| my $scale = 0; 31#| # Find how many initial digits are the same 32#| while ($lower < 1 || 33#| int($lower) == int($upper)) { 34#| $lower *= 10; 35#| $upper *= 10; 36#| $scale++; 37#| } 38#| while ($lower >= 10 && 39#| int($lower) == int($upper)) { 40#| $lower /= 10; 41#| $upper /= 10; 42#| $scale--; 43#| } 44#|} 45 46#--------------------------------------------------------------------- 47# Format a number, optionally with a +/- delta, to n significant 48# digits. 49# 50# @param significant digit, a value >= 1 51# @param multiplier 52# @param time in seconds to be formatted 53# @optional delta in seconds 54# 55# @return string of the form "23" or "23 +/- 10". 56# 57sub formatNumber { 58 my $sigdig = shift; 59 my $mult = shift; 60 my $a = shift; 61 my $delta = shift; # may be undef 62 63 my $result = formatSigDig($sigdig, $a*$mult); 64 if (defined($delta)) { 65 my $d = formatSigDig($sigdig, $delta*$mult); 66 # restrict PRECISION of delta to that of main number 67 if ($result =~ /\.(\d+)/) { 68 # TODO make this work for values with all significant 69 # digits to the left of the decimal, e.g., 1234000. 70 71 # TODO the other thing wrong with this is that it 72 # isn't rounding the $delta properly. Have to put 73 # this logic into formatSigDig(). 74 my $x = length($1); 75 $d =~ s/\.(\d{$x})\d+/.$1/; 76 } 77 $result .= " $PLUS_MINUS " . $d; 78 } 79 $result; 80} 81 82#--------------------------------------------------------------------- 83# Format a time, optionally with a +/- delta, to n significant 84# digits. 85# 86# @param significant digit, a value >= 1 87# @param time in seconds to be formatted 88# @optional delta in seconds 89# 90# @return string of the form "23 ms" or "23 +/- 10 ms". 91# 92sub formatSeconds { 93 my $sigdig = shift; 94 my $a = shift; 95 my $delta = shift; # may be undef 96 97 my @MULT = (1 , 1e3, 1e6, 1e9); 98 my @SUFF = ('s' , 'ms', 'us', 'ns'); 99 100 # Determine our scale 101 my $i = 0; 102 #always do seconds if the following line is commented out 103 ++$i while ($a*$MULT[$i] < 1 && $i < @MULT); 104 105 formatNumber($sigdig, $MULT[$i], $a, $delta) . ' ' . $SUFF[$i]; 106} 107 108#--------------------------------------------------------------------- 109# Format a percentage, optionally with a +/- delta, to n significant 110# digits. 111# 112# @param significant digit, a value >= 1 113# @param value to be formatted, as a fraction, e.g. 0.5 for 50% 114# @optional delta, as a fraction 115# 116# @return string of the form "23 %" or "23 +/- 10 %". 117# 118sub formatPercent { 119 my $sigdig = shift; 120 my $a = shift; 121 my $delta = shift; # may be undef 122 123 formatNumber($sigdig, 100, $a, $delta) . '%'; 124} 125 126#--------------------------------------------------------------------- 127# Format a number to n significant digits without using exponential 128# notation. 129# 130# @param significant digit, a value >= 1 131# @param number to be formatted 132# 133# @return string of the form "1234" "12.34" or "0.001234". If 134# number was negative, prefixed by '-'. 135# 136sub formatSigDig { 137 my $n = shift() - 1; 138 my $a = shift; 139 140 local $_ = sprintf("%.${n}e", $a); 141 my $sign = (s/^-//) ? '-' : ''; 142 143 my $a_e; 144 my $result; 145 if (/^(\d)\.(\d+)e([-+]\d+)$/) { 146 my ($d, $dn, $e) = ($1, $2, $3); 147 $a_e = $e; 148 $d .= $dn; 149 $e++; 150 $d .= '0' while ($e > length($d)); 151 while ($e < 1) { 152 $e++; 153 $d = '0' . $d; 154 } 155 if ($e == length($d)) { 156 $result = $sign . $d; 157 } else { 158 $result = $sign . substr($d, 0, $e) . '.' . substr($d, $e); 159 } 160 } else { 161 die "Can't parse $_"; 162 } 163 $result; 164} 165 1661; 167 168#eof 169