format_si_value(): Use the timestamp type in the calculation

diff --git a/pv/util.cpp b/pv/util.cpp
index 192a2e06ba1571766bbab637e1135d1980b5904a..78b32af7920c5de0caf354fe8a99c5066ed0ec24 100644 (file)
--- a/pv/util.cpp
+++ b/pv/util.cpp
@@ -25,6 +25,7 @@
 #include <assert.h>
 
 #include <algorithm>
+#include <sstream>
 
 #include <QTextStream>
 #include <QDebug>
@@ -34,49 +35,98 @@ using namespace Qt;
 namespace pv {
 namespace util {
 
-static const QString SIPrefixes[17] =
-       {"y", "z", "a", "f", "p", "n", QChar(0x03BC), "m", "", "k", "M", "G",
-       "T", "P", "E", "Z", "Y"};
-const int FirstSIPrefix = 8;
-const int FirstSIPrefixPower = -(FirstSIPrefix * 3);
+static const QString SIPrefixes[17] = {
+       "y", "z",
+       "a", "f", "p",
+       "n", QChar(0x03BC), "m",
+       "",
+       "k", "M", "G",
+       "T", "P", "E",
+       "Z", "Y"};
+const int EmptySIPrefix = 8;
+const int FirstSIPrefixPower = -(EmptySIPrefix * 3);
 const double MinTimeDelta = 1e-15; // Anything below 1 fs can be considered zero
 
-static QString format_si_value(double v, QString unit, int prefix,
+// Insert the timestamp value into the stream in fixed-point notation
+// (and honor the precision)
+static QTextStream& operator<<(QTextStream& stream, const Timestamp& t)
+{
+       // The multiprecision types already have a function and a stream insertion
+       // operator to convert them to a string, however these functions abuse a
+       // precision value of zero to print all available decimal places instead of
+       // none, and the boost authors refuse to fix this because they don't want
+       // to break buggy code that relies on this bug.
+       // (https://svn.boost.org/trac/boost/ticket/10103)
+       // Therefore we have to work around the case where precision is zero.
+
+       int precision = stream.realNumberPrecision();
+
+       std::ostringstream ss;
+       ss << std::fixed;
+
+       if (stream.numberFlags() & QTextStream::ForceSign) {
+               ss << std::showpos;
+       }
+
+       if (0 == precision) {
+               ss
+                       << std::setprecision(1)
+                       << round(t);
+       } else {
+               ss
+                       << std::setprecision(precision)
+                       << t;
+       }
+
+       std::string str(ss.str());
+       if (0 == precision) {
+               // remove the separator and the unwanted decimal place
+               str.resize(str.size() - 2);
+       }
+
+       return stream << QString::fromStdString(str);
+}
+
+QString format_si_value(const Timestamp& v, QString unit, int prefix,
        unsigned int precision, bool sign)
 {
        if (prefix < 0) {
-               int exp = -FirstSIPrefixPower;
-
-               prefix = 0;
-               while ((fabs(v) * pow(10.0, exp)) > 999.0 &&
-                       prefix < (int)(countof(SIPrefixes) - 1)) {
-                       prefix++;
-                       exp -= 3;
+               // No prefix given, calculate it
+
+               if (v.is_zero()) {
+                       prefix = EmptySIPrefix;
+               } else {
+                       int exp = -FirstSIPrefixPower;
+
+                       prefix = 0;
+                       while ((fabs(v) * pow(10.0, exp)) > 999.0 &&
+                               prefix < (int)(countof(SIPrefixes) - 1)) {
+                               prefix++;
+                               exp -= 3;
+                       }
                }
        }
 
        assert(prefix >= 0);
        assert(prefix < (int)countof(SIPrefixes));
 
-       const double multiplier = pow(10.0,
+       const Timestamp multiplier = pow(Timestamp(10),
                (int)- prefix * 3 - FirstSIPrefixPower);
 
        QString s;
        QTextStream ts(&s);
-       if (sign)
+       if (sign && !v.is_zero())
                ts << forcesign;
-       ts << fixed << qSetRealNumberPrecision(precision) <<
-               (v  * multiplier) << " " << SIPrefixes[prefix] << unit;
+       ts
+               << qSetRealNumberPrecision(precision)
+               << (v * multiplier)
+               << ' '
+               << SIPrefixes[prefix]
+               << unit;
 
        return s;
 }
 
-QString format_si_value(const Timestamp& v, QString unit, int prefix,
-       unsigned int precision, bool sign)
-{
-       return format_si_value(v.convert_to<double>(), unit, prefix, precision, sign);
-}
-
 static QString pad_number(unsigned int number, int length)
 {
        return QString("%1").arg(number, length, 10, QChar('0'));
@@ -156,7 +206,7 @@ static QString format_time_with_si(double t, QString unit, int prefix,
                -(prefix * 3 + pv::util::FirstSIPrefixPower);
 
        const unsigned int relative_prec =
-               (prefix >= pv::util::FirstSIPrefix) ? precision :
+               (prefix >= EmptySIPrefix) ? precision :
                std::max((int)(precision - prefix_order), 0);
 
        return format_si_value(t, unit, prefix, relative_prec);
@@ -189,7 +239,7 @@ QString format_time(const Timestamp& t, int prefix, TimeUnit unit, unsigned int
 
 QString format_second(const Timestamp& second)
 {
-       return format_si_value(second.convert_to<double>(), "s", -1, 0, false);
+       return format_si_value(second, "s", -1, 0, false);
 }
 
 } // namespace util

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 726d7070402e8025f591bd17f6330bb48a2d2d3e..6e41d39aed8abcbe83b8b2135157706663b91293 100644 (file)
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -73,6 +73,7 @@ set(pulseview_TEST_SOURCES
        data/analogsegment.cpp
        data/logicsegment.cpp
        test.cpp
+       util.cpp
 )
 
 # This list includes only QObject derived class headers.

diff --git a/test/util.cpp b/test/util.cpp
new file mode 100644 (file)
index 0000000..1e33790
--- /dev/null
+++ b/test/util.cpp
@@ -0,0 +1,144 @@
+/*
+ * This file is part of the PulseView project.
+ *
+ * Copyright (C) 2015 Jens Steinhauser <jens.steinhauser@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+#include <boost/test/unit_test.hpp>
+
+#include "pv/util.hpp"
+
+using namespace pv::util;
+using ts = pv::util::Timestamp;
+
+namespace {
+       QChar mu = QChar(0x03BC);
+}
+
+std::ostream& operator<<(std::ostream& stream, const QString& str)
+{
+       return stream << str.toUtf8().data();
+}
+
+BOOST_AUTO_TEST_SUITE(UtilTest)
+
+BOOST_AUTO_TEST_CASE(format_si_value_test)
+{
+       // check prefix calculation
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("0"), "V"), "0 V");
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-24"), "V"),   "+1 yV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-23"), "V"),  "+10 yV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-22"), "V"), "+100 yV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-21"), "V"),   "+1 zV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-20"), "V"),  "+10 zV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-19"), "V"), "+100 zV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-18"), "V"),   "+1 aV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-17"), "V"),  "+10 aV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-16"), "V"), "+100 aV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-15"), "V"),   "+1 fV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-14"), "V"),  "+10 fV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-13"), "V"), "+100 fV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-12"), "V"),   "+1 pV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-11"), "V"),  "+10 pV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-10"), "V"), "+100 pV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-9"), "V"),    "+1 nV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-8"), "V"),   "+10 nV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-7"), "V"),  "+100 nV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-6"), "V"),   QString("+1 ") + mu + "V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-5"), "V"),  QString("+10 ") + mu + "V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-4"), "V"), QString("+100 ") + mu + "V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-3"), "V"),    "+1 mV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-2"), "V"),   "+10 mV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-1"), "V"),  "+100 mV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e0"), "V"),      "+1 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e1"), "V"),     "+10 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e2"), "V"),    "+100 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e3"), "V"),     "+1 kV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e4"), "V"),    "+10 kV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e5"), "V"),   "+100 kV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e6"), "V"),     "+1 MV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e7"), "V"),    "+10 MV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e8"), "V"),   "+100 MV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e9"), "V"),     "+1 GV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e10"), "V"),   "+10 GV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e11"), "V"),  "+100 GV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e12"), "V"),    "+1 TV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e13"), "V"),   "+10 TV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e14"), "V"),  "+100 TV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e15"), "V"),    "+1 PV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e16"), "V"),   "+10 PV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e17"), "V"),  "+100 PV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e18"), "V"),    "+1 EV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e19"), "V"),   "+10 EV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e20"), "V"),  "+100 EV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e21"), "V"),    "+1 ZV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e22"), "V"),   "+10 ZV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e23"), "V"),  "+100 ZV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e24"), "V"),    "+1 YV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e25"), "V"),   "+10 YV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e26"), "V"),  "+100 YV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e27"), "V"), "+1000 YV");
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("1234"), "V"),           "+1 kV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1234"), "V", 9, 3), "+1.234 kV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1234.5678"), "V"),      "+1 kV");
+
+       // check if a given prefix is honored
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-24"), "V", 0),    "+1 yV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-21"), "V", 0), "+1000 yV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("0"), "V", 0),         "0 yV");
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-4"), "V", 7),       "+0 mV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-4"), "V", 7, 1),  "+0.1 mV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1000"), "V", 7), "+1000000 mV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("0"), "V", 7),           "0 mV");
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-1"), "V", 8),       "+0 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-1"), "V", 8, 1),  "+0.1 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e-1"), "V", 8, 2), "+0.10 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1"), "V", 8),          "+1 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e1"), "V", 8),       "+10 V");
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e23"), "V", 16),       "+0 YV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e23"), "V", 16, 1),  "+0.1 YV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1e27"), "V", 16),    "+1000 YV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("0"), "V", 16),           "0 YV");
+
+       // check precision
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.2345678"), "V"),                "+1 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.4"), "V"),                      "+1 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.5"), "V"),                      "+2 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.9"), "V"),                      "+2 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.2345678"), "V", -1, 2),      "+1.23 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.2345678"), "V", -1, 3),     "+1.235 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.2345678"), "V", 7, 3),  "+1234.568 mV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.2345678"), "V", 7, 0),      "+1235 mV");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1.2"), "V", -1, 3),           "+1.200 V");
+
+       // check sign
+
+       BOOST_CHECK_EQUAL(format_si_value(ts("-1"), "V", 8, 0, true),  "-1 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("-1"), "V", 8, 0, false), "-1 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1"), "V", 8, 0, true),   "+1 V");
+       BOOST_CHECK_EQUAL(format_si_value(ts("1"), "V", 8, 0, false),   "1 V");
+}
+
+BOOST_AUTO_TEST_SUITE_END()