已知x = np.matrix([1, 2, 3, 4, 5])，那么表达式x*x.T的值为matrix([[55]])。

After excuting the statement "[X,D]=eig(A)", D is（ ）. A: a scalar matrix B: an identity matrix C: a triangular matrix D: a diagonal matrix

NP问题(NP)，NP完全问题(NPC)，NP难问题(NP-hard)，三者之间的关系为（ ）。 A: NPC=NP∩NP-hard B: NP=NPC∩NP-hard C: NP-hard =NP∩NPC D: NPÍNPCÍNP-hard

对于NP难问题和NP完全问题的说法正确的是() A: NP难问题和NP完全问题是等价的 B: NP难问题一定是NP类问题 C: 所有NP难问题都是NP完全问题 D: 所有NP完全问题都是NP难问题

关于P问题、NP问题、NP完全问题，下面说法正确的是（ ） A: P=NP B: 有的NP问题无法约化为可满足性问题 C: NP完全问题都是NP问题 D: NP问题都是NP完全问题

If A is a matrix, the function max(A(:)) is ( ). A: to return the first element B: to return the maximum element in each row of the matrix C: to return the maximum element in each column of the matrix D: to return the largest element of the entire matrix

14 In triple sequence table of sparse matrix, each triple represents ( ). A: the row number,column number and data value of non-zero elements in the matrix B: the data value of non-zero elements in the matrix C: the row and column numbers of elements in the matrix D: the row number,column number and data value of elements in the matrix

Let A be a 4 by 3 matrix, and r(A)=2, and B is an invertible matrix, then r(AB)=______

If A is a matrix, the function of the function max(a(:)) is ( ). A: to work out the maximum element of the entire matrix B: function call errors C: to work out the maximum element of each row of the matrix D: to work out the maximum element of each column of the matrix

Windows 98包含了几种网络提供者(NP)，其中______是16位的实模式程序。 ( ) A: WinNet16 NP B: NetWare NP C: Win32 NP D: Windows NP