D=1 1 1 1 1 2 4 8 1 3 9 27 1 4 16 64 D=1*2*3*1*2*1=12 D为什么等于12 怎么算的?线性代数这是一个4*4的行列式

\d{4}[^\d]\d{1,2}[^\d]\d{1,2} 请问这个正则表达是什么意思? 1D,2D,3D,4D我知道了.5D是啥意思? 用Mathematica解决下面的问题有一个数组：dd={{d[3]-5,d[2]-1,d[1]},{d[2]-5,d[1]-1,d[3]},{d[1]-5,d[3]-1,d[2]},{d[3]-4,d[2]-2,d[1]},{d[2]-4,d[1]-2,d[3]},{d[1]-4,d[3]-2,d[2]}{d[3]-3,d[2]-2,d[1]-1},{d[2]-3,d[1]-2,d[3]-1},{d[1]-3,d[3]-2,d[2]-1} /^d{1,8}$|.d{1,2}$/ Excel =SUMPRODUCT((D$2:D$19>D2)*(1/(COUNTIF(D$2:D$19,D$2:D$19))))+1在excel中有个中国式排序的函数,=SUMPRODUCT((D$2:D$19>D2)*(1/(COUNTIF(D$2:D$19,D$2:D$19))))+1我会运用这个函数了,而且也知道1/(countif（D$2:D$19,D$2:D$19))的 请问~1D（一维）2D,3D,4D,5D分别怎么区分怎么判别谢谢 2D是什么意思还有1D和3D java 正则表达式匹配IP加个判断String regex = ^(1\d{2}|2[0-4]\d|25[0-5]|[1-9]\d|[1-9])\. + (1\d{2}|2[0-4]\d|25[0-5]|[1-9]\d|\d)\.+ (1\d{2}|2[0-4]\d|25[0-5]|[1-9]\d|\d)\. + (1\d{2}|2[0-4]\d|25[0-5]|[1-9]\d|\d)$;加 1D和4D什么意思? SUM(--(N(OFFSET(D$1,IF(D$1:D$100=13,ROW(D$1:D$100),4^8),))=ROW(A1)))是什么意思啊?特别是(--(N(?看不懂, 纳米粒子的1D,2D, 应该是个java正则 ^[0-9]{6}$##^123456|234567|345678|654321|765432|876543|456789|987654|012345|543210|098765|567890|(\d{1})\1\1(\d{1})\2\2|(\d{3})\3|(\d{1})\4(\d{1})\5(\d{1})\6|(\d{1})(\d{1})\7\8\7\8|\d{1}\d{1}(\d{1})\9{3} 化简{[2*1d+3*2d+4*3d+……+n(n-1)d]+n(n-1)/2*d*a}/[(n-1)n*d/2] 关于方差的两条性质的问题就是方差的两条性质：1、D(aX)=a2 D(X) 2、若X、Y相互独立则D(X+Y)=D(X)+D(Y).那么根据1：D(2X)=4 D(X) 根据2、D(X+X)=D(X)+D(X)=2D(X), C语言 int a;int b; }d[3] ={{1,4},{2,5},{6,7}}; printf(%d ,d[2].a* d[2].b/d[1].b);struct num{int a;int b;}d[3] ={{1,4},{2,5},{6,7}};则执行printf(%d ,d[2].a* d[2].b/d[1].b); 语句的输出结果是：（）.A.2B.2.5C.8D.8.4 1+1=?DF D DF DF D FD FD F D FDDFDF D FD 为毛loop 语句缺少do?Dim d(1 To 15) As DoubleDim i As DoubleDim flag As DoubleDim key As DoubleDim m As Doubled(1) = 0d(2) = 2d(3) = 3d(4) = 6d(5) = 7d(6) = 9d(7) = 11d(8) = 12d(9) = 13d(10) = 15d(11) = 18d(12) = 19d(13) = 20d(14) = 24d(15) = 25 1D,1.5D,2.5D,4D弯头分别在什么时候使用