Question

我正在编写一个程序，让用户输入一个分母和一个分母，程序然后将其转换为混合形式（9/8 - > 1 1/8等等）。除了分母大于提名者之外，它的工作正常。当我开始调试代码时，我发现了一些我无法理解的东西。下面是方法分数，在它结束时调用方法gcd（最大公共分频器）来确定将整数除法的余数和分母分开的内容。

public static int[] fraction(int nominator, int denominator) //Rewrites a fraction to mixed form
{

                                  //nominator == 7 and denominator == 8

    int[] result = {0, 0, 0};
    int quotient;
    int remainder;
    if (denominator == 0)
        return null;
    if (nominator == 0)
    {
        result[0] = 0;
        result[1] = 0;
        result[2] = 0;
        return result;
    }
    kvot = nominator/denominator;
    rest = nominator % denominator;
    result[0] = quotient;
    result[1] = remainder/(gcd(remainder, denominator));    //According to the debugger, the values are still 7 and 8 here
    result[2] = denominator/(gcd(remainder, denominator));


    return result;
}

当使用上述值调用时，似乎出现了问题，因为第二种方法从第一种方法中获取的值是错误的。而不是7和8，它接收7和1.是否提供了代码中的错误，或者它似乎是在其他地方？

public static int gcd(int a, int b) //Calculates the greatest common divider for two integers


{  //The debugger tells me that a == 7 and b == 1, even though the method was called with 7 and 8

int temp, c;

if (b == 0)
{
    System.out.println("Nominator is 0, error");;
}
if (b > a)
        {
            temp = b;
            b = a;
            a = temp;
        }

    c = a % b;
    a = b;
    b = c;

    return a;

}

Answer 1

您的gcd功能不正常。如果您使用欧几里德算法，您可以像这样计算gcd

var pieGenerator = d3.pie()
  .value(function(d) {return d.quantity;})
  .sort(function(a, b) {
    return a.name.localeCompare(b.name);
  });

var fruits = [
  {name: 'Apples', quantity: 20},
  {name: 'Bananas', quantity: 40},
  {name: 'Cherries', quantity: 50},
  {name: 'Damsons', quantity: 10},
  {name: 'Elderberries', quantity: 30},
];
var fruits2 = [
  {name: 'Blueberries', quantity: 40},
  {name: 'Bananas', quantity: 40},
  {name: 'Cherries', quantity: 50},
  {name: 'Damsons', quantity: 10},
  {name: 'Elderberries', quantity: 30},
];

var arcGenerator = d3.arc()
  .innerRadius(75)
  .outerRadius(200)
  .padAngle(.02)
  .padRadius(100)
  .cornerRadius(4);

function doUpdate() {
  update(fruits2);
}

function update(myData) {

  var arcData = pieGenerator(myData);
  var colorDomain = myData.map(function(a) {return a.name;});
  var colorScale = d3.scaleOrdinal()
    .domain(colorDomain)
    .range(['#ff2800','#58595B','#006c93','#8D2048','#00746F'])

  // Create a path element and set its d attribute
  var u = d3.select('g')
    .selectAll('path')
    .data(arcData);

  u.enter()
    .append('path')
    .attr('d', arcGenerator)
    .each(function(d){
      d3.select(this)
        .style('fill',function(d) {
          return colorScale(d.data.name);
        })
    });

  u.exit().remove();

你也可以使用其他一些解决方案，但建议不行。

为什么我的方法没有使用正确的值调用我的其他方法？

1 个答案: