QGIS API Documentation 3.29.0-Master (006c3c0232)
qgsbasicnumericformat.cpp
Go to the documentation of this file.
1/***************************************************************************
2 qgsbasicnumericformat.cpp
3 ----------------------------
4 begin : January 2020
5 copyright : (C) 2020 by Nyall Dawson
6 email : nyall dot dawson at gmail dot com
7
8 ***************************************************************************
9 * *
10 * This program is free software; you can redistribute it and/or modify *
11 * it under the terms of the GNU General Public License as published by *
12 * the Free Software Foundation; either version 2 of the License, or *
13 * (at your option) any later version. *
14 * *
15 ***************************************************************************/
16
18#include "qgis.h"
19#include <memory>
20#include <iostream>
21#include <locale>
22#include <iomanip>
23
24struct formatter : std::numpunct<wchar_t>
25{
26 formatter( QChar thousands, bool showThousands, QChar decimal )
27 : mThousands( thousands.unicode() )
28 , mDecimal( decimal.unicode() )
29 , mShowThousands( showThousands )
30 {}
31 wchar_t do_decimal_point() const override { return mDecimal; }
32 wchar_t do_thousands_sep() const override { return mThousands; }
33 std::string do_grouping() const override { return mShowThousands ? "\3" : "\0"; }
34
35 wchar_t mThousands;
36 wchar_t mDecimal;
37 bool mShowThousands = true;
38};
39
41{
42}
43
45{
46 return QStringLiteral( "basic" );
47}
48
50{
51 return QObject::tr( "Number" );
52}
53
55{
56 return 1;
57}
58
59QString QgsBasicNumericFormat::formatDouble( double value, const QgsNumericFormatContext &context ) const
60{
61 const QChar decimal = mDecimalSeparator.isNull() ? context.decimalSeparator() : mDecimalSeparator;
62 std::basic_stringstream<wchar_t> os;
63 os.imbue( std::locale( os.getloc(), new formatter( mThousandsSeparator.isNull() ? context.thousandsSeparator() : mThousandsSeparator,
64 mShowThousandsSeparator,
65 decimal ) ) );
66
67 if ( !mUseScientific )
68 {
69 switch ( mRoundingType )
70 {
71 case DecimalPlaces:
72 os << std::fixed << std::setprecision( mNumberDecimalPlaces );
73 if ( qgsDoubleNear( value, 0 ) )
74 os << 0.0;
75 else
76 os << value;
77
78 break;
79
81 {
82 if ( qgsDoubleNear( value, 0 ) )
83 {
84 os << std::fixed << std::setprecision( mNumberDecimalPlaces - 1 ) << 0.0;
85 }
86 else
87 {
88 // digits before decimal point
89 const int d = std::floor( std::log10( value < 0 ? -value : value ) ) + 1;
90 const double order = std::pow( 10.0, mNumberDecimalPlaces - d );
91 os << std::fixed << std::setprecision( std::max( mNumberDecimalPlaces - d, 0 ) ) << std::round( value * order ) / order;
92 }
93 break;
94 }
95 }
96 }
97 else
98 {
99 os << std::scientific << std::setprecision( mNumberDecimalPlaces );
100 if ( qgsDoubleNear( value, 0 ) )
101 os << 0.0;
102 else
103 os << value;
104 }
105
106 QString res = QString::fromStdWString( os.str() );
107
108 if ( mShowPlusSign && value > 0 )
109 res.prepend( context.positiveSign() );
110
111 if ( !mShowTrailingZeros && res.contains( decimal ) )
112 {
113 int trimPoint = res.length() - 1;
114 int ePoint = 0;
115 if ( mUseScientific )
116 {
117 while ( res.at( trimPoint ).toUpper() != context.exponential().toUpper() )
118 trimPoint--;
119 ePoint = trimPoint;
120 trimPoint--;
121 }
122
123 while ( res.at( trimPoint ) == context.zeroDigit() )
124 trimPoint--;
125
126 if ( res.at( trimPoint ) == decimal )
127 trimPoint--;
128
129 const QString original = res;
130 res.truncate( trimPoint + 1 );
131 if ( mUseScientific )
132 res += original.mid( ePoint );
133 }
134
135 return res;
136}
137
139{
140 return new QgsBasicNumericFormat( *this );
141}
142
143QgsNumericFormat *QgsBasicNumericFormat::create( const QVariantMap &configuration, const QgsReadWriteContext &context ) const
144{
145 std::unique_ptr< QgsBasicNumericFormat > res = std::make_unique< QgsBasicNumericFormat >();
146 res->setConfiguration( configuration, context );
147 return res.release();
148}
149
151{
152 QVariantMap res;
153 res.insert( QStringLiteral( "decimals" ), mNumberDecimalPlaces );
154 res.insert( QStringLiteral( "show_thousand_separator" ), mShowThousandsSeparator );
155 res.insert( QStringLiteral( "show_plus" ), mShowPlusSign );
156 res.insert( QStringLiteral( "show_trailing_zeros" ), mShowTrailingZeros );
157 res.insert( QStringLiteral( "rounding_type" ), static_cast< int >( mRoundingType ) );
158 res.insert( QStringLiteral( "thousand_separator" ), mThousandsSeparator.isNull() ? QVariant() : QVariant::fromValue( mThousandsSeparator ) );
159 res.insert( QStringLiteral( "decimal_separator" ), mDecimalSeparator.isNull() ? QVariant() : QVariant::fromValue( mDecimalSeparator ) );
160 return res;
161}
162
163void QgsBasicNumericFormat::setConfiguration( const QVariantMap &configuration, const QgsReadWriteContext & )
164{
165 mNumberDecimalPlaces = configuration.value( QStringLiteral( "decimals" ), 6 ).toInt();
166 mShowThousandsSeparator = configuration.value( QStringLiteral( "show_thousand_separator" ), true ).toBool();
167 mShowPlusSign = configuration.value( QStringLiteral( "show_plus" ), false ).toBool();
168 mShowTrailingZeros = configuration.value( QStringLiteral( "show_trailing_zeros" ), false ).toBool();
169 mRoundingType = static_cast< RoundingType >( configuration.value( QStringLiteral( "rounding_type" ), static_cast< int >( DecimalPlaces ) ).toInt() );
170 mThousandsSeparator = configuration.value( QStringLiteral( "thousand_separator" ), QChar() ).toChar();
171 mDecimalSeparator = configuration.value( QStringLiteral( "decimal_separator" ), QChar() ).toChar();
172}
173
175{
176 return mNumberDecimalPlaces;
177}
178
180{
181 mNumberDecimalPlaces = numberDecimalPlaces;
182}
183
185{
186 return mShowThousandsSeparator;
187}
188
189void QgsBasicNumericFormat::setShowThousandsSeparator( bool showThousandsSeparator )
190{
191 mShowThousandsSeparator = showThousandsSeparator;
192}
193
195{
196 return mShowPlusSign;
197}
198
200{
201 mShowPlusSign = showPlusSign;
202}
203
205{
206 return mShowTrailingZeros;
207}
208
210{
211 mShowTrailingZeros = showTrailingZeros;
212}
213
215{
216 return mRoundingType;
217}
218
220{
221 mRoundingType = type;
222}
223
225{
226 return mThousandsSeparator;
227}
228
230{
231 mThousandsSeparator = character;
232}
233
235{
236 return mDecimalSeparator;
237}
238
240{
241 mDecimalSeparator = character;
242}
QgsNumericFormat * create(const QVariantMap &configuration, const QgsReadWriteContext &context) const override
Creates a new copy of the format, using the supplied configuration.
QChar thousandsSeparator() const
Returns any override for the thousands separator character.
RoundingType
Sets rounding type and behavior of the numberDecimalPlaces() setting.
@ DecimalPlaces
Maximum number of decimal places.
@ SignificantFigures
Maximum number of significant figures.
void setThousandsSeparator(QChar character)
Sets an override character for the thousands separator character.
QgsBasicNumericFormat()
Default constructor.
void setShowTrailingZeros(bool show)
Sets whether trailing zeros will be shown (up to the specified numberDecimalPlaces()).
void setShowThousandsSeparator(bool show)
Sets whether the thousands grouping separator will be shown.
bool showThousandsSeparator() const
Returns true if the thousands grouping separator will be shown.
QString id() const override
Returns a unique id for this numeric format.
virtual void setConfiguration(const QVariantMap &configuration, const QgsReadWriteContext &context)
Sets the format's configuration.
RoundingType roundingType() const
Returns the rounding type, which controls the behavior of the numberDecimalPlaces() setting.
QString visibleName() const override
Returns the translated, user-visible name for this format.
int sortKey() override
Returns a sorting key value, where formats with a lower sort key will be shown earlier in lists.
bool showTrailingZeros() const
Returns true if trailing zeros will be shown (up to the specified numberDecimalPlaces()).
void setRoundingType(RoundingType type)
Sets the rounding type, which controls the behavior of the numberDecimalPlaces() setting.
QgsNumericFormat * clone() const override
Clones the format, returning a new object.
bool showPlusSign() const
Returns true if a leading plus sign will be shown for positive values.
QChar decimalSeparator() const
Returns any override for the decimal separator character.
void setShowPlusSign(bool show)
Sets whether a leading plus sign will be shown for positive values.
QString formatDouble(double value, const QgsNumericFormatContext &context) const override
Returns a formatted string representation of a numeric double value.
virtual void setNumberDecimalPlaces(int places)
Sets the maximum number of decimal places to show.
int numberDecimalPlaces() const
Returns the maximum number of decimal places to show.
QVariantMap configuration(const QgsReadWriteContext &context) const override
Returns the current configuration of the formatter.
void setDecimalSeparator(QChar character)
Sets an override character for the decimal separator character.
A context for numeric formats.
QChar thousandsSeparator() const
Returns the thousands separator character.
QChar zeroDigit() const
Returns the zero digit character.
QChar exponential() const
Returns the exponential character.
QChar decimalSeparator() const
Returns the decimal separator character.
QChar positiveSign() const
Returns the positive sign character.
A numeric formatter allows for formatting a numeric value for display, using a variety of different f...
The class is used as a container of context for various read/write operations on other objects.
bool qgsDoubleNear(double a, double b, double epsilon=4 *std::numeric_limits< double >::epsilon())
Compare two doubles (but allow some difference)
Definition: qgis.h:2915
wchar_t do_decimal_point() const override
std::string do_grouping() const override
wchar_t do_thousands_sep() const override
formatter(QChar thousands, bool showThousands, QChar decimal)