(1)特殊向量 t=[0:0.1:10] %产生从0~10的行向量,元素之间的间隔为0.1 t=linspace(n1,n2,n) %产生n1和n2之间线性均匀分布的n个数(默认n时,产生100个数) t=lonspace(n1,n2,n) %默认n时,产生50个数 (2)特殊矩阵 eye(m) %生成m阶单位矩阵 eye(m,n) %m阶
(1)特殊向量
t=[0:0.1:10] %产生从0~10的行向量,元素之间的间隔为0.1
t=linspace(n1,n2,n) %产生n1和n2之间线性均匀分布的n个数(默认n时,产生100个数)
t=lonspace(n1,n2,n) %默认n时,产生50个数
(2)特殊矩阵
eye(m) %生成m阶单位矩阵
eye(m,n) %m阶单位矩阵的第n列
eye(size(a)) %与矩阵a同等阶数的单位阵
(3)所有元素为1的矩阵(也叫全1矩阵)
ones(n) %全1的n阶矩阵
ones(size(A)) %与A同阶的全1矩阵
ones(m,n) %m阶全1矩阵的第n列
(4)所有元素为0的矩阵(也叫全0矩阵)
zeros(n) %全0的n阶矩阵
zeros(size(A)) %与A同阶的全0矩阵
zeros(m,n) %m阶全0矩阵的第n列
(5)空矩阵
q=[] %空矩阵是一个特殊的矩阵,这在线性代数中是不存在的。不过,它可以用来删除矩阵的行与列。
B(2,:)=[] %删除矩阵B的第2行
B(:,3)=[] %删除矩阵B的第3列
(6)随机数矩阵
rand(m,n) %产生m×n矩阵,其中的元素是服从[0,1]上均匀分布的随机数;
normrnd(mu,sigma,m,n) %产生m×n矩阵,其中的元素是服从均值为mu、标准差为sigma的正态分布的随机数;
exprnd(mu,m,n) %产生m×n矩阵,其中的元素是服从均值为mu的指数分布的随机数;
poissrnd(mu,m,n) %产生m×n矩阵,其中的元素是服从均值为mu的泊松分布的随机数;
unifrnd(a,b,m,n) %产生m×n矩阵,其中的元素是服从区间[a,b]山均匀分布的随机数;
(7)随机置换
randperm(n) %产生1~n的一个随机全排列
perms([1:n]) %产生1~n的所有全排列
(8)求矩阵的逆
inv(a) %求矩阵a的逆
(9)方阵b对应的行列式的值
det(b) %方阵b对应的行列式的值

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