Java 用负分数除的问题
我正在做一个编码作业,我应该写一些方法来简化,求gcf,加,减,乘,除两个分数。我已经写了所有的方法,但是我在divide方法中遇到了麻烦,因为每当我尝试除以一个负分数(比如-6/17),它就会打印出0/1作为结果。这是我所有方法的分数类,但我添加的唯一方法是上面列出的方法。其余的都是我的导师提供的。下面是课程:Java 用负分数除的问题,java,class,methods,fractions,divide,Java,Class,Methods,Fractions,Divide,我正在做一个编码作业,我应该写一些方法来简化,求gcf,加,减,乘,除两个分数。我已经写了所有的方法,但是我在divide方法中遇到了麻烦,因为每当我尝试除以一个负分数(比如-6/17),它就会打印出0/1作为结果。这是我所有方法的分数类,但我添加的唯一方法是上面列出的方法。其余的都是我的导师提供的。下面是课程: class Fraction { private int numerator = 0; // numerator (and keeps sign) private in
class Fraction {
private int numerator = 0; // numerator (and keeps sign)
private int denominator = 1; // always stores positive value
public Fraction() {
}
public Fraction(int n, int d) {
if (set(n, d) == false)
set(0, 1);
}
public boolean set(int n, int d) {
if (d > 0) {
numerator = n;
denominator = d;
return true;
} else
return false;
}
public String toString() {
return (numerator + "/" + denominator);
}
public int getNumerator() {
return numerator;
}
public int getDenominator() {
return denominator;
}
public double decimal() {
return (double) numerator / denominator;
}
public Fraction simplify(){
int gcd = GetGcd(this);
int simpNum = this.numerator;
int simpDen = this.denominator;
simpNum /= gcd;
simpDen /= gcd;
Fraction f = new Fraction (simpNum, simpDen);
return f;
}
public int GetGcd (Fraction f){
int testNum = f.numerator;
int testDen = f.denominator;
if (testNum < 0)
testNum = 0 - testNum;
else if (testDen < 0)
testDen = 0 - testDen;
if (testNum == 0){
return testDen;
}
while (testNum != testDen){
if (testNum > testDen)
testNum -= testDen;
else
testDen -= testNum;
}
return testNum;
}
public Fraction add (Fraction f){
int cd = this.denominator * f.denominator;
int den1 = this.denominator;
int den2 = f.denominator;
int num1 = this.numerator * (cd / den1);
int num2 = f.numerator * (cd / den2);
int num3 = num1 + num2;
Fraction f2 = new Fraction (num3, cd);
f2 = f2.simplify();
return f2;
}
public Fraction subtract (Fraction f){
int cd = this.denominator * f.denominator;
int den1 = this.denominator;
int den2 = f.denominator;
int num1 = this.numerator * (cd / den1);
int num2 = f.numerator * (cd / den2);
int num3 = num1 - num2;
Fraction f2 = new Fraction (num3, cd);
f2 = f2.simplify();
return f2;
}
public Fraction multiply (Fraction f){
int den1 = this.denominator;
int den2 = f.denominator;
int num1 = this.numerator;
int num2 = f.numerator;
int num3 = num1 * num2;
int den3 = den1 * den2;
Fraction f2 = new Fraction (num3, den3);
f2 = f2.simplify();
return f2;
}
public Fraction divide (Fraction f){
int den1 = this.denominator;
int den2 = f.denominator;
int num1 = this.numerator;
int num2 = f.numerator;
int num3 = num1 * den2;
int den3 = den1 * num2;
Fraction f2 = new Fraction (num3, den3);
f2 = f2.simplify();
return f2;
}
}
结果应如下所示:
4/6 simplified = 2/3
75/175 simplified = 3/7
-6/17 simplified = -6/17
f1 = 4/6
f2 = 75/175
f3 = -6/17
4/6 + 75/175 = 23/21
4/6 - 75/175 = 5/21
4/6 * 75/175 = 2/7
4/6 / 75/175 = 14/9
75/175 + -6/17 = 9/119
75/175 - -6/17 = 93/119
75/175 * -6/17 = -18/119
75/175 / -6/17 = -17/14 (THIS SHOWS UP AS 0/1 INSTEAD...)
75/175 / 0/1 = 0/1
我知道这是除法的一部分,因为当我在上一个方法中将-6/17改为6/17时,它工作正常,简化后打印出17/14。我只是不知道除法中的什么不适用于负分数。我是否可以在这里添加一些东西来帮助解决这个问题?提前感谢。在divide()中
假设此
为正,而f
为负。根据你的假设,
den1 > 0
den2 > 0
num1 > 0
num2 < 0
num3 = num1 * den2 > 0
den3 = den1 * num2 < 0
当分母小于0时,返回false
,禁止将值设置到类中
您可以将分子和分母的符号都倒过来,而不是简单地返回false
尝试将设置方法更改为:
public boolean set(int n, int d) {
if (d > 0) {
numerator = n;
denominator = d;
return true;
}
else if (d < 0) {
numerator = n * -1;
denominator = d * -1;
return true;
}
else
return false;
}
公共布尔集合(int n,int d){
如果(d>0){
分子=n;
分母=d;
返回true;
}
else如果(d<0){
分子=n*-1;
分母=d*-1;
返回true;
}
其他的
返回false;
}
如果没有第二个if
语句,set
将对具有负demoninator的分数求值为false。在这种情况下,divide
方法返回的分数将是0/1。当我尝试在set()
中反转分子和分母的符号时,它为最后一个除法问题输出75/175/6/17=17/14
。由于这将它们的符号从-6/17改为6/17,所以我尝试在用Divide()
相乘之前反转分子的符号。除了答案的符号外,这一切都起了作用。我得到了75/175/-6/17=17/14
。我怎么能把答案的符号改成-17/14的正确答案?好吧,我知道了!我把if(num2<0){num2=0-num2;num3=0-num3;}
放在Divide()
中两个乘法问题之间,它打印了-17/14。谢谢你的帮助!这里的第一个答案可能对你有帮助兄弟,
den1 > 0
den2 > 0
num1 > 0
num2 < 0
num3 = num1 * den2 > 0
den3 = den1 * num2 < 0
public boolean set(int n, int d) {
if (d > 0) {
numerator = n;
denominator = d;
return true;
} else
return false;
}
public boolean set(int n, int d) {
if (d > 0) {
numerator = n;
denominator = d;
return true;
}
else if (d < 0) {
numerator = n * -1;
denominator = d * -1;
return true;
}
else
return false;
}