matlab實驗報告二.docx

Matlab實驗報告實驗2 數(shù)值數(shù)組及運算一、 實驗?zāi)康模?） 掌握一維數(shù)組、二維數(shù)組、多項式和高維數(shù)組的創(chuàng)建（2） 掌握對數(shù)組操作的常用函數(shù)二、 實驗內(nèi)容使用冒號運算符創(chuàng)建下面各表達(dá)式對應(yīng)的向量。 x=logspace(1,3,3); x=10.1:3x = 10 100 1000 x=logspace(1,3,5)x = 1.0e+003 * 0.0100 0.0316 0.1000 0.3162 1.0000利用MATLAB內(nèi)置函數(shù)計算下面的值 cosh(5)ans = 74.2099 sinh(-2)ans = -3.6269 (exp(5)+exp(-5)/2ans = 74.2099 help erf ERF Error function. Y = ERF(X) is the error function for each element of X. X must be real. The error function is defined as: erf(x) = 2/sqrt(pi) * integral from 0 to x of exp(-t2) dt. Class support for input X: float: double, single See also erfc, erfcx, erfinv. Overloaded functions or methods (ones with the same name in other directories) help sym/erf.m Reference page in Help browser doc erf erf(1.2)ans = 0.9103利用linspace函數(shù)創(chuàng)建下面表達(dá)式的對應(yīng)向量 x=0:10; x=linspace(0,10,11)x = 0 1 2 3 4 5 6 7 8 9 10 x=0:0.2:10; x=linspace(0,10,51)x = Columns 1 through 16 0 0.2000 0.4000 0.6000 0.8000 1.0000 1.2000 1.4000 1.6000 1.8000 2.0000 2.2000 2.4000 2.6000 2.8000 3.0000 Columns 17 through 32 3.2000 3.4000 3.6000 3.8000 4.0000 4.2000 4.4000 4.6000 4.8000 5.0000 5.2000 5.4000 5.6000 5.8000 6.0000 6.2000 Columns 33 through 48 6.4000 6.6000 6.8000 7.0000 7.2000 7.4000 7.6000 7.8000 8.0000 8.2000 8.4000 8.6000 8.8000 9.0000 9.2000 9.4000 Columns 49 through 51 9.6000 9.8000 10.0000 x=-12:12; x=linspace(-12,12,25)x = -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 x=10:-1:1; x=linspace(10,1,10)x = 10 9 8 7 6 5 4 3 2 1 x=10 9 8 7x = 10 9 8 7 x=10 9 8 7;y=1 2 3 4; z=x-y; zz = 9 7 5 3計算 A=1 2 3 3;2 3 5 7;1 3 5 7;3 2 3 9;1 8 9 4; B=1+4i 4 3 6 7;2 3 3 5 5;2 6+7i 5 3 4;1 8 9 4 3; C=A*B; CC = 1.0e+002 * 0.1400 + 0.0400i 0.5200 + 0.2100i 0.5100 0.3700 0.3800 0.2500 + 0.0800i 1.0300 + 0.3500i 1.0300 0.7000 0.7000 0.2400 + 0.0400i 0.9900 + 0.3500i 1.0000 0.6400 0.6300 0.2200 + 0.1200i 1.0800 + 0.2100i 1.1100 0.7300 0.7000 0.3900 + 0.0400i 1.1400 + 0.6300i 1.0800 0.8900 0.9500 D=C(4:5,3:5); DD = 111 73 70 108 89 95 A=1 2 3 3;2 3 5 7;1 3 5 7;3 2 3 9;1 8 9 4; A=1 2 3 3;2 3 5 7;1 3 5 7;3 2 3 9;1 8 9 4A = 1 2 3 3 2 3 5 7 1 3 5 7 3 2 3 9 1 8 9 4 A=4 12 20;12 45 78;20 78 136; B=1 2 3;4 5 6;7 8 0; I=1 0 0;0 1 0;0 0 1; A+5*Bans = 9 22 35 32 70 108 55 118 136 A-B+Ians = 4 10 17 8 41 72 13 70 137 A.*Bans = 4 24 60 48 225 468 140 624 0 A*Bans = 192 228 84 738 873 306 1284 1518 528 A.Bans = 1.0e+015 * 0.0000 0.0000 0.0000 0.0000 0.0000 0.0002 0.0000 1.3701 0.0000 ABWarning: Matrix is close to singular or badly scaled. Results may be inaccurate. RCOND = 1.328379e-018.ans = 1.0e+015 * 0.0000 -0.0000 3.6192 -0.0000 0.0000 -7.2384 0.0000 -0.0000 3.6192 A/Bans = 9.3333 -1.3333 0.0000 40.0000 -7.0000 0.0000 70.6667 -12.6667 0.0000 A(find(A50)&(A B(find(B5)ans = 7 8 6 A=1 2 NaN Inf -Inf 5 NaNA = 1 2 NaN Inf -Inf 5 NaN isnan(A)ans = 0 0 1 0 0 0 1 isfinite(A)ans = 1 1 0 0 0 1 0 isinf(A)ans = 0 0 0 1 1 0 0 any(A)ans = 1 all(A)ans = 1求出以下矩陣的逆矩陣 A=1 -5 -2;3 4 -9;-7 2 6A = 1 -5 -2 3 4 -9 -7 2 6 B=sin(1) sin(-5) sin(-2);sin(3) sin(4) sin(9); sin(-7) sin(2) sin(6)B = 0.8415 0.9589 -0.9093 0.1411 -0.7568 0.4121 -0.6570 0.9093 -0.2794 inv(A)ans = -0.1673 -0.1036 -0.2112 -0.1793 0.0319 -0.0120 -0.1355 -0.1315 -0.0757 inv(B)ans = 6.8645 23.4969 12.3171 9.7255 35.0011 19.9746 15.5090 58.6555 32.4631 A=1 2 3;4 5 6;7 8 9; B=flipud(A)B = 7 8 9 4 5 6 1 2 3 u=1 2 3; v=4 5 6; A=u;vA = 1 2 3 4 5 6用兩行語句實現(xiàn)從C中引用列向量 C=11 5;5 1;18 7; s=C(:,1)s = 11 5 18 t=C(:,2)t = 5 1 7使用diag函數(shù)和冒號運算符創(chuàng)建下面矩陣 diag(1:1:4)ans = 1 0 0 0 0 2 0 0 0 0 3 0 0 0 0 4 diag(4:-1:1)ans = 4 0 0 0 0 3 0 0 0 0 2 0 0 0 0 1 diag(1:6:19)ans = 1 0 0 0 0 7 0 0 0 0 13 0 0 0 0 19使用diag函數(shù)創(chuàng)建nxn對稱三對角陣 a=2 2 2 2; b=-1 -1 -1; D=diag(a)+diag(b,-1)+diag(b,1)D = 2 -1 0 0 -1 2 -1 0 0 -1 2 -1 0 0 -1 2創(chuàng)建矩陣 e=eye(3); E=fliplr(e)E = 0 0 1 0 1 0 1 0 0 a=2*eye(5)-ones(5)a = 1 -1 -1 -1 -1 -1 1 -1 -1 -1 -1 -1 1 -1 -1 -1 -1 -1 1 -1 -1 -1 -1 -1 1 b=tril(a)b = 1 0 0 0 0 -1 1 0 0 0 -1 -1 1 0 0 -1 -1 -1 1 0 -1 -1 -1 -1 1 b(:,5)=1b = 1 0 0 0 1 -1 1 0 0 1 -1 -1 1 0 1 -1 -1 -1 1 1 -1 -1 -1 -1 1使用rehape函數(shù)和冒號運算符創(chuàng)建矩陣 reshape(2:2:24,3,4)ans = 2 8 14 20 4 10 16 22 6 12 18 24 reshape(-5:1:6,2,6)ans = -5 -3 -1 1 3 5 -4 -2 0 2 4 6（a）找出每個矩陣各列中絕對值最大的元素（b）找出每個矩陣各行中絕對值最大的元素 c=C(:,1)c = 11 2 1 max(real(c)ans = 11 d=C(:,2)d = -4 2 11 max(real(d)ans = 11 e=C(1,:)e = 11 -4 max(real(e)ans = 11 f=C(2,:)f = 2 2 max(real(f)ans = 2 c=D(:,1)c = 13 2 13 max(real(c)ans = 13 d=D(:,2)d = -6 2 23 max(real(d)ans = 23 e=D(1,:)e = 13 -6 max(real(e)ans = 13 f=D(2,:)f = 2 2 max(real(f)ans = 2 c=E(:,1)c = 4.5000 -3.0000 -0.7500 max(real(c)ans = 4.5000 d=E(:,2)d = 1.0000 1.0000 1.7500 max(real(d)ans = 1.7500 e=E(1,:)e = 4.5000 1.0000 max(real(e)ans = 4.5000 f=E(2,:)f = -3 1 max(real(f)ans = 1思考下面的程序 A=ones(3,2); B=2*ones(2,3); A*B; A(2,3)=2; A*B;? Error using = mtimesInner matrix dimensions must agree. A*B? Error using = mtimesInner matrix dimensions must agree. u=0:3; v=(3:-1:0); w=u.*v;? Error using = timesMatrix dimensions must agree. clear all A=ones(3,3); A(k,k)? Undefined function or variable k. A(i,i)? Subscript indices must either be real positive integers or logicals.定義多項式 a=1 -12 25 6; p=poly2sym(a) p = x3-12*x2+25*x+6 x(2)求下面矩陣的特征多項式 D=2 -1 0 0;-1 2 -1 0;0 -1 2 -1;0 0 -1 2; PA=