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javaËÄÉáÎåÈëBigDecimal

javaËÄÉáÎåÈë
package Test;
import java.math.BigDecimal; //ÒýÈëÕâ¸ö°ü
public class Test {
  public static void main(String[] args) {
   double i = 3.856;
   // ÉáµôСÊýÈ¡Õû
   System.out.println("ÉáµôСÊýÈ¡Õû:Math.floor(3.856)=" + (int) Math.floor(i));
   // ËÄÉáÎåÈëÈ¡Õû
   System.out.println("ËÄÉáÎåÈëÈ¡Õû:(3.856)="
     + new BigDecimal(i).setScale(0, BigDecimal.ROUND_HALF_UP));
   // ËÄÉáÎåÈë±£ÁôÁ½Î»Ð¡Êý
   System.out.println("ËÄÉáÎåÈëÈ¡Õû:(3.856)="
     + new BigDecimal(i).setScale(2, BigDecimal.ROUND_HALF_UP));
   // ´ÕÕû£¬È¡ÉÏÏÞ
   System.out.println("´ÕÕû:Math.ceil(3.856)=" + (int) Math.ceil(i));
   // ÉáµôСÊýÈ¡Õû
   System.out.println("ÉáµôСÊýÈ¡Õû:Math.floor(-3.856)=" + (int) Math.floor(-i));
   // ËÄÉáÎåÈëÈ¡Õû
   System.out.println("ËÄÉáÎåÈëÈ¡Õû:(-3.856)="
     + new BigDecimal(-i).setScale(0, BigDecimal.ROUND_HALF_UP));
   // ËÄÉáÎåÈë±£ÁôÁ½Î»Ð¡Êý
   System.out.println("ËÄÉáÎåÈëÈ¡Õû:(-3.856)="
     + new BigDecimal(-i).setScale(2, BigDecimal.ROUND_HALF_UP));
   // ´ÕÕû£¬È¡ÉÏÏÞ
   System.out.println("´ÕÕû(-3.856)=" + (int) Math.ceil(-i));
  }
}
//´òÓ¡µÄ½á¹û
ÉáµôСÊýÈ¡Õû:Math.floor(3.856)=3
ËÄÉáÎåÈëÈ¡Õû:(3.856)=4
ËÄÉáÎåÈëÈ¡Õû:(3.856)=3.86
´ÕÕû:Math.ceil(3.856)=4
ÉáµôСÊýÈ¡Õû:Math.floor(-3.856)=-4
ËÄÉáÎåÈëÈ¡Õû:(-3.856)=-4
ËÄÉáÎåÈëÈ¡Õû:(-3.856)=-3.86
´ÕÕû(-3.856)=-3


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