pv/util.cpp

   1 /*
   2  * This file is part of the PulseView project.
   3  *
   4  * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "util.hpp"
  21
  22 #include <extdef.h>
  23
  24 #include <assert.h>
  25
  26 #include <algorithm>
  27 #include <sstream>
  28
  29 #include <QTextStream>
  30 #include <QDebug>
  31
  32 using namespace Qt;
  33
  34 namespace pv {
  35 namespace util {
  36
  37 static QTextStream& operator<<(QTextStream& stream, SIPrefix prefix)
  38 {
  39         switch (prefix) {
  40         case SIPrefix::yocto: return stream << 'y';
  41         case SIPrefix::zepto: return stream << 'z';
  42         case SIPrefix::atto:  return stream << 'a';
  43         case SIPrefix::femto: return stream << 'f';
  44         case SIPrefix::pico:  return stream << 'p';
  45         case SIPrefix::nano:  return stream << 'n';
  46         case SIPrefix::micro: return stream << QChar(0x03BC);
  47         case SIPrefix::milli: return stream << 'm';
  48         case SIPrefix::kilo:  return stream << 'k';
  49         case SIPrefix::mega:  return stream << 'M';
  50         case SIPrefix::giga:  return stream << 'G';
  51         case SIPrefix::tera:  return stream << 'T';
  52         case SIPrefix::peta:  return stream << 'P';
  53         case SIPrefix::exa:   return stream << 'E';
  54         case SIPrefix::zetta: return stream << 'Z';
  55         case SIPrefix::yotta: return stream << 'Y';
  56
  57         default: return stream;
  58         }
  59 }
  60
  61 int exponent(SIPrefix prefix)
  62 {
  63         return 3 * (static_cast<int>(prefix) - static_cast<int>(SIPrefix::none));
  64 }
  65
  66 static SIPrefix successor(SIPrefix prefix)
  67 {
  68         assert(prefix != SIPrefix::yotta);
  69         return static_cast<SIPrefix>(static_cast<int>(prefix) + 1);
  70 }
  71
  72 // Insert the timestamp value into the stream in fixed-point notation
  73 // (and honor the precision)
  74 static QTextStream& operator<<(QTextStream& stream, const Timestamp& t)
  75 {
  76         // The multiprecision types already have a function and a stream insertion
  77         // operator to convert them to a string, however these functions abuse a
  78         // precision value of zero to print all available decimal places instead of
  79         // none, and the boost authors refuse to fix this because they don't want
  80         // to break buggy code that relies on this bug.
  81         // (https://svn.boost.org/trac/boost/ticket/10103)
  82         // Therefore we have to work around the case where precision is zero.
  83
  84         int precision = stream.realNumberPrecision();
  85
  86         std::ostringstream ss;
  87         ss << std::fixed;
  88
  89         if (stream.numberFlags() & QTextStream::ForceSign)
  90                 ss << std::showpos;
  91
  92         if (0 == precision)
  93                 ss << std::setprecision(1) << round(t);
  94         else
  95                 ss << std::setprecision(precision) << t;
  96
  97         std::string str(ss.str());
  98         if (0 == precision) {
  99                 // remove the separator and the unwanted decimal place
 100                 str.resize(str.size() - 2);
 101         }
 102
 103         return stream << QString::fromStdString(str);
 104 }
 105
 106 QString format_time_si(
 107         const Timestamp& v,
 108         SIPrefix prefix,
 109         unsigned int precision,
 110         QString unit,
 111         bool sign)
 112 {
 113         if (prefix == SIPrefix::unspecified) {
 114                 // No prefix given, calculate it
 115
 116                 if (v.is_zero()) {
 117                         prefix = SIPrefix::none;
 118                 } else {
 119                         int exp = exponent(SIPrefix::yotta);
 120                         prefix = SIPrefix::yocto;
 121                         while ((fabs(v) * pow(Timestamp(10), exp)) > 999 &&
 122                                         prefix < SIPrefix::yotta) {
 123                                 prefix = successor(prefix);
 124                                 exp -= 3;
 125                         }
 126                 }
 127         }
 128
 129         assert(prefix >= SIPrefix::yocto);
 130         assert(prefix <= SIPrefix::yotta);
 131
 132         const Timestamp multiplier = pow(Timestamp(10), -exponent(prefix));
 133
 134         QString s;
 135         QTextStream ts(&s);
 136         if (sign && !v.is_zero())
 137                 ts << forcesign;
 138         ts
 139                 << qSetRealNumberPrecision(precision)
 140                 << (v * multiplier)
 141                 << ' '
 142                 << prefix
 143                 << unit;
 144
 145         return s;
 146 }
 147
 148 QString format_time_si_adjusted(
 149         const Timestamp& t,
 150         SIPrefix prefix,
 151         unsigned precision,
 152         QString unit,
 153         bool sign)
 154 {
 155         // The precision is always given without taking the prefix into account
 156         // so we need to deduct the number of decimals the prefix might imply
 157         const int prefix_order = -exponent(prefix);
 158
 159         const unsigned int relative_prec =
 160                 (prefix >= SIPrefix::none) ? precision :
 161                 std::max((int)(precision - prefix_order), 0);
 162
 163         return format_time_si(t, prefix, relative_prec, unit, sign);
 164 }
 165
 166
 167 // Helper for 'format_time_minutes()'.
 168 static QString pad_number(unsigned int number, int length)
 169 {
 170         return QString("%1").arg(number, length, 10, QChar('0'));
 171 }
 172
 173 QString format_time_minutes(const Timestamp& t, signed precision, bool sign)
 174 {
 175         const Timestamp whole_seconds = floor(abs(t));
 176         const Timestamp days = floor(whole_seconds / (60 * 60 * 24));
 177         const unsigned int hours = fmod(whole_seconds / (60 * 60), 24).convert_to<uint>();
 178         const unsigned int minutes = fmod(whole_seconds / 60, 60).convert_to<uint>();
 179         const unsigned int seconds = fmod(whole_seconds, 60).convert_to<uint>();
 180
 181         QString s;
 182         QTextStream ts(&s);
 183
 184         if (t < 0)
 185                 ts << "-";
 186         else if (sign)
 187                 ts << "+";
 188
 189         bool use_padding = false;
 190
 191         // DD
 192         if (days) {
 193                 ts << days.str().c_str() << ":";
 194                 use_padding = true;
 195         }
 196
 197         // HH
 198         if (hours || days) {
 199                 ts << pad_number(hours, use_padding ? 2 : 0) << ":";
 200                 use_padding = true;
 201         }
 202
 203         // MM
 204         ts << pad_number(minutes, use_padding ? 2 : 0);
 205
 206         ts << ":";
 207
 208         // SS
 209         ts << pad_number(seconds, 2);
 210
 211         if (precision) {
 212                 ts << ".";
 213
 214                 const Timestamp fraction = fabs(t) - whole_seconds;
 215
 216                 std::ostringstream ss;
 217                 ss
 218                         << std::fixed
 219                         << std::setprecision(precision)
 220                         << std::setfill('0')
 221                         << fraction;
 222                 std::string fs = ss.str();
 223
 224                 // Copy all digits, inserting spaces as unit separators
 225                 for (int i = 1; i <= precision; i++) {
 226                         // Start at index 2 to skip the "0." at the beginning
 227                         ts << fs.at(1 + i);
 228
 229                         if ((i > 0) && (i % 3 == 0) && (i != precision))
 230                                 ts << " ";
 231                 }
 232         }
 233
 234         return s;
 235 }
 236
 237 } // namespace util
 238 } // namespace pv