怎么在MATLAB里输入一个矩阵？ MATLAB中如何直接输入矩阵
\u600e\u4e48\u5728matlab\u4e2d\u8f93\u5165\u53d8\u91cf\u7684\u77e9\u9635a=zeros(61); % \u5168\u90e8\u5143\u7d20\u4e3a0\u7684\u77e9\u9635
b=ones(61); %\u5168\u90e8\u5143\u7d20\u4e3a1\u7684\u77e9\u9635
MATLAB\u5982\u4f55\u5b9a\u4e49\u53d8\u91cf
\u60c5\u51b5\u4e00\uff1a\u7b26\u53f7\u53d8\u91cf
\u5fc5\u987b\u8981\u5b9a\u4e49\uff0c\u5b9a\u4e49\u4e4b\u540e\u624d\u53ef\u4ee5\u4f7f\u7528\u3002\u5982\u4e0b\u9762\u7684\u4f8b\u5b50\uff0c\u672a\u5b9a\u4e49\u5c31\u4f1a\u51fa\u9519\u3002
\u7b26\u53f7\u53d8\u91cf\u5b9a\u4e49\u65b9\u6cd5\u4f8b\u5982: sym x \u6216\u8005 syms x \uff0c\u4e24\u8005\u6709\u533a\u522b\u4e5f\u6709\u5171\u540c\u70b9\u3002
\u60c5\u51b5\u4e8c\uff1a\u8ba1\u7b97\u8fc7\u7a0b\u5f53\u4e2d\u7684\u5b58\u50a8\u6570\u503c\u7684\u53d8\u91cf
\u53ef\u4ee5\u4e0d\u5fc5\u5b9a\u4e49\uff0c\u968f\u65f6\u9700\u8981\uff0c\u968f\u65f6\u5b9a\u4e49\uff0c\u4f46\u662f\u6709\u65f6\u5019\u5982\u679c\u53d8\u91cf\u5f88\u591a\uff0c\u90a3\u4e48\u6700\u597d\u63d0\u524d\u58f0\u660e\uff0c\u58f0\u660e\u7684\u65f6\u5019\uff0c\u53ef\u4ee5\u76f4\u63a5\u8d4b\u4e880\u503c\uff0c\u5e76\u4e14\u6ce8\u91ca\uff0c\u8fd9\u6837\u65b9\u4fbf\u4ee5\u540e\u533a\u5206\uff0c\u907f\u514d\u6df7\u6dc6\u3002
\u60c5\u51b5\u4e09\uff1a\u77e9\u9635\u548c\u5411\u91cf
\u5bf9\u4e8e\u77e9\u9635\u4e00\u822c\u90fd\u662f\u9700\u8981\u5b9a\u4e49\u7684\uff0c\u5b9a\u4e49\u597d\u77e9\u9635\u4e4b\u540e\uff0c\u624d\u65b9\u4fbf\u8bbf\u95ee/\u4fee\u6539\u77e9\u9635\u7684\u6307\u5b9a\u5143\u7d20\uff0c\u77e9\u9635\u58f0\u660e\uff08\u5b9a\u4e49\uff09\u7684\u65b9\u6cd5\uff0c\u5e38\u7528\u7684 \u5c31\u662f\u58f0\u660e\u4e3a\u96f6\u77e9\u9635zeros(M,N),\u6216\u8005\u5355\u4f4d\u77e9\u9635ones(M,N),eye(M,N)\u7b49\u3002
%1.\u8bd5\u5206\u522b\u751f\u6210 5 \u9636\u7684\u5355\u4f4d\u9635\u30018 \u9636\u5747\u5300\u5206\u5e03\u7684\u968f\u673a\u77e9\u9635\u53ca\u5176\u4e0b\u4e09\u89d2\u77e9\u9635
a=eye(5)\uff1bb=rand(8)\uff1bc=tril(b)
%2.\u751f\u4ea7\u5217\u5411\u91cf x=[1, 3, 5, 7, 9, \u2026 , 29]
x=[1;3;5;7;9;11;13;15;17;19;21;23;25;27;29] \uff1b%\u65b9\u6cd51
y=[1:2:29]\u2018 \uff1b %\u65b9\u6cd52
z=[linspace(1,29,15)]\u2018 \uff1b%\u65b9\u6cd53
%3.\u751f\u6210\u4ee5 x \u7684\u524d 5 \u4e2a\u5143\u7d20\u4e3a\u5bf9\u89d2\u7ebf\u7684\u77e9\u9635
AA=diag(x(1:5))
%4.\u751f\u6210\u4e00\u4e2a\u4e0e A \u540c\u9636\u7684\u6b63\u6001\u5206\u5e03\u7684\u968f\u673a\u77e9\u9635 B
A=ones(6)\uff1bc=size(A)\uff1bB=randn(c) \uff1b%\u60c5\u51b51%
A1=ones(5,6)\uff1bc1=size(A1)\uff1bB1=randn(c1) \uff1b%\u60c5\u51b52
%5.\u751f\u6210\u7531 B \u4e0e\u5176\u540c\u9636\u9b54\u65b9\u77e9\u9635\u70b9\u4e58\u5f97\u5230\u7684\u77e9\u9635 D
b=size(B)\uff1bb1=magic(b)\uff1bD=B.*b1
%6.\u751f\u6210\u7531 D \u7684\u7b2c 2\u30014\u30015 \u884c\u548c\u7b2c4\u30011 \u5217\u7ec4\u6210\u7684\u5b50\u77e9\u9635 E
E=D([2,4,5],[4,1])
如何用MATLAB里输入aij和bi矩阵?该问题可以这样来实现。
（1），对于aij，可以使用双循环for语句再加条件if语句，即
aij用a(i,j)数组来表示，当j=i时，a(i,j)=2*i；当i>=1 & j==i+1时，a(i,j)=-1；当i>=2 & j==i-1时，a(i,j)=-1；其他，a(i,j)=0
（2），对于bi，可以使用单循环for语句，即
bi用b(i)数组来表示，b(i)=1.5*i-6;
（3），实现代码
clc,close all
for i=1:40
b(i)=1.5*i-6;
for j=1:40
if j==i
a(i,j)=2*i;
elseif i>=1 & j==i+1
a(i,j)=-1;
elseif i>=2 & j==i-1
a(i,j)=-1;
else
a(i,j)=0;
end
end
end
a,b
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绛旓細y=[1:2:29]鈥 锛 %鏂规硶2 z=[linspace(1,29,15)]鈥 锛%鏂规硶3 3.鐢熸垚浠 x 鐨鍓 5 涓厓绱犱负瀵硅绾跨殑鐭╅樀 AA=diag(x(1:5))4.鐢熸垚涓涓涓 A 鍚岄樁鐨勬鎬佸垎甯冪殑闅忔満鐭╅樀 B A=ones(6)锛沜=size(A)锛汢=randn(c) 锛%鎯呭喌1 A1=ones(5,6)锛沜1=size(A1)锛汢1=randn(c1) 锛%...
绛旓細clc;clear allN=5000;k=8;h=50;Te=40;a=h+2*k*N^2;b=-k*N^2;B=eye(N-2)*b;A=eye(N-1)*a;A(2:N-1,1:N-2)=B;A(1:N-2,2:N-1)=B;hTe=ones(N-1,1)*h*Te;T=A\hTe;
绛旓細clear clc n=4;N=4*n;% N x N 鐭╅樀 L_2=-2*ones(1,N);L10=repmat([1 1 1 0],1,n);L10(end)=[];L1=ones(1,N-4);缁撴灉 L=diag(L1,-4)+diag(L10,-1)+diag(L_2);L=L+L'
