Java-格式化双数据类型,获取错误
这是我的家庭作业代码。我早就应该这样做了,我在这方面做得不太好,但我想努力克服我的错误和问题,以便在学校里做得更好;但无论如何:Java-格式化双数据类型,获取错误,java,format,printf,Java,Format,Printf,这是我的家庭作业代码。我早就应该这样做了,我在这方面做得不太好,但我想努力克服我的错误和问题,以便在学校里做得更好;但无论如何: double x1, y1, x2, y2, x3, y3; // Three points for three vertices. // (x1, y1), (x2, y2), (x3, y3) Scanner input = new Scanner(System.in); // T
double x1, y1, x2, y2, x3, y3; // Three points for three vertices.
// (x1, y1), (x2, y2), (x3, y3)
Scanner input = new Scanner(System.in);
// The program asks the user what the name of the triangle is. Then the program
// asks the user for the cordinates of each point.
System.out.print("Enter a three letter name for the triangle: ");
String triangleName = input.next();
System.out.print("Coordinates of vertex " + triangleName.substring(0,1).toUpperCase() + ":");
x1 = input.nextDouble();
y1 = input.nextDouble();
System.out.print("Coordinates of vertex " + triangleName.substring(1,2).toUpperCase() + ":");
x2 = input.nextDouble();
y2 = input.nextDouble();
System.out.print("Coordinates of vertex " + triangleName.substring(2,3).toUpperCase() + ":");
x3 = input.nextDouble();
y3 = input.nextDouble();
double a, b, c; // These values will serve as the three side
// lengths between the points.
// The program displays side lengths in this block.
System.out.println("--- Side lengths ---");
a = Math.sqrt(Math.pow(x2-x1, 2) + Math.pow(y2-y1, 2));
System.out.printf(triangleName.substring(0,1).toUpperCase()
+ triangleName.substring(1,2).toUpperCase() + ":"
+ "%.3f", a);
System.out.println();
b = Math.sqrt(Math.pow(x3-x2, 2) + Math.pow(y3-y2, 2));
System.out.printf(triangleName.substring(1,2).toUpperCase()
+ triangleName.substring(2,3).toUpperCase() + ":"
+ "%.3f", b);
System.out.println();
c = Math.sqrt(Math.pow(x3-x1, 2) + Math.pow(y3-y1, 2));
System.out.printf(triangleName.substring(2,3).toUpperCase()
+ triangleName.substring(0,1).toUpperCase() + ":"
+ "%.3f", c);
System.out.println();
double perimeter, area, xCentroid, yCentroid, inRadius, inArea, semiPerimeter, triangleHeight, triangleBase;
// The program displays other measures in this block.
System.out.println("--- Other measures ---");
perimeter = a + b + c;
System.out.printf("Perimeter = " + "%.3f", perimeter);
System.out.println();
triangleHeight = y3 - 0.1;
triangleBase = x2 - x1;
area = (triangleHeight * triangleBase) / 2;
System.out.printf("Area = " + "%.3f", area);
System.out.println();
xCentroid = (x1 + x2 + x3) / 3;
yCentroid = (y1 + y2 + y3) / 3;
System.out.printf("Centroid = ( " + "%.3f", xCentroid + ", " + yCentroid + ")");
System.out.println();
semiPerimeter = 0.5 * perimeter;
inRadius = area / semiPerimeter;
System.out.format("Incircle radius = " + "%.3f", inRadius);
System.out.println();
inArea = Math.PI * Math.pow(inRadius, 2);
System.out.format("Incircle area = " + "%.3f", inArea);
System.out.println();
代码中的问题存在于分别格式化xCentroid和yCentroid值的行中。我收到一个错误,上面写着java.util.IllegalFormatConversionException:f!=java.lang.String。程序中的数学运行良好,也很有效。我已经删除了语句中的%.3f,看看我是否得到了正确的答案,我做到了。只是这种格式让我很生气。请回复,并提供帮助。我要起床一会儿,要有耐心
新代码已修复:
System.out.print("Centroid = ");
System.out.print("(");
System.out.printf("%.3f", xCentroid);
System.out.print(", ");
System.out.printf("%.3f", yCentroid);
System.out.print(")");
System.out.println();
在此代码中
System.out.printf("Centroid = ( " + "%.3f", xCentroid + ", "
+ yCentroid + ")");
尤其是这个
xCentroid + ", " + yCentroid + ")"
不是一个数字,而是一个字符串
我猜你想要的是
System.out.printf("Centroid = (%.3f)", xCentroid + yCentroid);
请在发布前将问题减少到最低限度。你发布的大部分代码都是无关的,而且你还没有给我们完整的exmaple,我们只能复制/粘贴/编译/运行。很抱歉。请记住,以备将来参考!谢谢你告诉我。我对这整件事还不熟悉。肯定会在这个更频繁,将更好地张贴代码。