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    System.out.println(0.05 + 0.01);
    System.out.println(1.0 - 0.42);
    System.out.println(4.015 * 100);
    System.out.println(123.3 / 100);
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    0.060000000000000005
0.5800000000000001
401.49999999999994
1.2329999999999999
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public double round(double value){
return Math.round( value * 100 ) / 100.0;
}
µ«·Ç³£²»ÐÒµÄÊÇ£¬ÉÏÃæµÄ´úÂë²¢²»ÄÜÕý³£¹¤×÷£¬¸øÕâ¸ö·½·¨´«Èë4.015Ëü½«·µ»Ø4.01¶ø²»ÊÇ4.02£¬ÈçÎÒÃÇÔÚÉÏÃæ¿´µ½µÄ
4.015 * 100 = 401.49999999999994
Òò´ËÈç¹ûÎÒÃÇÒª×öµ½¾«È·µÄËÄÉáÎåÈ룬ÕâÖÖ·½·¨²»ÄÜÂú×ãÎÒÃǵÄÒªÇó¡£
»¹ÓÐÒ»ÖÖ·½Ê½ÊÇʹÓÃjava.text.DecimalFormat£¬µ«Ò²´æÔÚÎÊÌ⣬format²ÉÓõÄÉáÈëģʽÊÇROUND_HALF_DOWN£¨ÉáÈëģʽÔÚÏÂÃæÓнéÉÜ£©£¬±ÈÈç˵4.025±£ÁôÁ½Î»Ð¡Êý»áÊÇ4.02£¬ÒòΪ.025¾àÀë” nearest neighbor”£¨.02ºÍ.03£©³¤¶ÈÊÇÏàµÈ£¬ÏòÏÂÉáÈë¾ÍÊÇ.02£¬Èç¹ûÊÇ4.0251ÄÇô±£ÁôÁ½Î»Ð¡Êý¾ÍÊÇ4.03¡£
System.out.println(new java.text.DecimalFormat("0.00").format(4.025));
System.out.println(new java.text.DecimalFormat("0.00").format(4.0251));
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4.02
4.03
 
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    System.out.print


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