1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
|
//===========================================
// Lumina Desktop source code
// Copyright (c) 2016, Ken Moore
// Available under the 3-clause BSD license
// See the LICENSE file for full details
//===========================================
#include "mainUI.h"
#include "ui_mainUI.h"
#include <QDebug>
#define VALIDSYMBOLS QString("+-*x/.")
#include <math.h>
#define BADVALUE NAN
mainUI::mainUI() : QMainWindow(), ui(new Ui::mainUI()){
ui->setupUi(this);
connect(ui->tool_start, SIGNAL(clicked()), this, SLOT(start_calc()) );
connect(ui->line_eq, SIGNAL(returnPressed()), this, SLOT(start_calc()) );
ui->line_eq->setFocus();
}
mainUI::~mainUI(){
}
void mainUI::start_calc(){
if(ui->line_eq->text().isEmpty()){ return; } //nothing to do
double result = strToNumber(ui->line_eq->text());
if(result!=result){ return; } //bad calculation - NaN's values are special in that they don't equal itself
QString res = "%1 \t(%2)";
ui->list_results->addItem(res.arg(QString::number(result), ui->line_eq->text()));
ui->list_results->scrollToItem( ui->list_results->item( ui->list_results->count()-1) );
ui->line_eq->clear();
}
double mainUI::performOperation(double LHS, double RHS, QChar symbol){
if(symbol== '+'){ return (LHS+RHS); }
else if(symbol== '-'){ return (LHS-RHS); }
else if(symbol== '*' || symbol=='x'){ return (LHS*RHS); }
else if(symbol== '/'){ return (LHS/RHS); }
//else if(symbol== '%'){ return (LHS%RHS); }
qDebug() << "Invalid Symbol:" << symbol;
return BADVALUE;
}
double mainUI::strToNumber(QString str){
//Look for perentheses first
qDebug() << "String to Number: " << str;
if(str.indexOf("(")>=0){
//qDebug() << "Found Parenthesis";
int start = str.indexOf("(");
int need = 1;
int end = -1;
for(int i=start+1; i<str.length() && need>0; i++){
if(str[i]=='('){ need++; }
else if(str[i]==')'){ need--; }
//qDebug() << "Check char:" << str[i] << need;
if(need==0){ end = i; }
}
if(end<start){ return BADVALUE; }
//qDebug() << "Replace value:" << str << start << end << str.mid(start+1,end-start);
str.replace(start, end-start+1, QString::number( strToNumber( str.mid(start+1, end-start-1)) ) );
//qDebug() << "Replaced:" << str;
}
// -------------------------------------
// NOTE: the order of operations appears reversed here due to the recursive nature of the algorithm
// the first operation *found* is actually the last one *evaluated*
// --------------------------------------
//Now look for add/subtract
int sym = -1;
QStringList symbols; symbols << "+" << "-";
for(int i=0; i<symbols.length(); i++){
int tmp = str.indexOf(symbols[i]);
if(sym < tmp){ sym = tmp; }
}
if(sym>0){ return performOperation( strToNumber(str.left(sym)), strToNumber(str.right(str.length()-sym-1)), str[sym]); }
if(sym==0){ return BADVALUE; }
//Now look for multiply/divide
symbols.clear(); symbols << "x" << "*" << "/";
for(int i=0; i<symbols.length(); i++){
int tmp = str.indexOf(symbols[i]);
if(sym < tmp){ sym = tmp; }
}
if(sym>0){ return performOperation( strToNumber(str.left(sym)), strToNumber(str.right(str.length()-sym-1)), str[sym]); }
if(sym==0){ return BADVALUE; }
//Could not find any operations - must be a raw number
//qDebug() << "Found Number:" << str.toDouble();
return str.toDouble();
}
|
