Contents BISECTION ACCURACY .................................................................................................................................. 2 BISECTION ITERATION .................................................................................................................................. 3 NEWTON RAPHSON METOD ITERATION ..................................................................................................... 4 NEWTON RAPHSON ACCURACY................................................................................................................... 5 SUCCESSIVE APPROXIMATION ITERATION .................................................................................................. 6 SUCCESSIVE APPROXIMATION ACCURACY .................................................................................................. 7 GAUSS ELIMINATION.................................................................................................................................... 8 GAUSS SEIDAL METHOD ............................................................................................................................. 10 THOMAS ALGORITHM ................................................................................................................................ 12 TRAPEZOIDAL ............................................................................................................................................. 14 SIMPSONS 1/3RD ......................................................................................................................................... 15 SIMPSON 3/8th ............................................................................................................................................ 16 EULERS METHOD ........................................................................................................................................ 17 RK 4th ORDER ............................................................................................................................................. 18 RK 2 SIMULTANEOUS EQUATION .............................................................................................................. 20 MINIMIZATION ........................................................................................................................................... 21 LAPLACE EQUATION ................................................................................................................................... 22 Straight line ................................................................................................................................................ 23 POWER EQUATION (a*bx) .......................................................................................................................... 25 Power equation (axb) ................................................................................................................................. 27 QUADRATIC EQUATION ............................................................................................................................. 29 EXPONENTIAL ............................................................................................................................................. 31 LAGRANGES INTERPOLATION .................................................................................................................... 33 NEWTON FORWARD................................................................................................................................... 35 INVERSE INTERPOLATION .......................................................................................................................... 37 BISECTION ACCURACY %program for bisection method by accuracy f=inline('x*x-8*x+2'); x1=input('\n enter initial guess x1='); x2=input('\n enter initial guess x2='); acc=input('\n enter accuracy acc='); y1=f(x1); y2=f(x2); while(y1*y2>0) x1=input('\n enter initial guess x1='); x2=input('\n enter initial guess x2='); y1=f(x1); y2=f(x2); end while(abs(x2-x1)>acc) x3=(x1+x2)/2; y3=f(x3); if(y1*y3<0) x2=x3; y2=y3; else x1=x3; y1=y3; end end fprintf('\n the root of new equation=%f',x3); OUTPUT >>bisectionaccuracy enter initial guess x1=0 enter initial guess x2=1 enter accuracy acc=0.01 the root of new equation=0.2578>> SOLVER >> x=fzero(inline(‘x*x-8*x+2),0); >>x x= 0.2578 BISECTION ITERATION %program for bisection method by iteration f=inline(' x*exp(x)-3.1*cos(x)'); x1=input('\n enter initial guess x1='); x2=input('\n enter initial guess x2='); n=input('\n enter noof iteration n='); y1=f(x1); y2=f(x2); while(y1*y2>0) x1=input('\n enter initial guess x1='); x2=input('\n enter initial guess x2='); y1=f(x1); y2=f(x2); end for i=1:n x3=(x1+x2)/2; y3=f(x3); if(y1*y3<0) x2=x3; y2=y3; else x1=x3; y1=y3; end end fprintf('\n the root of new equation=%f',x3); OUTPUT >bisectioniteration enter initial guess x1=0 enter initial guess x2=1 entern of iteration n=8 the root of new equation=0.8554>> solver >> f=inline(‘x*exp(x)-3.1*cos(x)’); >> x=fzero(f,2.8,3); >>x x = 0.8554 NEWTON RAPHSON METOD ITERATION f=inline('x*x*x-5*x+3'); df=inline('3*x*x-5'); ddf=inline('6*x'); x1=input('\n enter initial guess x1='); n=input('\n enter no of iteration n='); y1=f(x1); y2=df(x1); y3=ddf(x1); a=(y1*y3)/(y2*y2); while(abs(a)>1) x1=input('\n enter initial guess x1='); y1=f(x1); y2=df(x1); y3=ddf(x1); a=(y1*y3)/(y2*y2); end for i=1:n x2=x1-(y1/y2); x1=x2; y1=f(x1); y2=df(x1); end fprintf('\n the root of equation=%f',x2); OUTPUT >>newtonraphsoniteration enter initial guess x1=0 enter no of iteration n=3 the root of equation=0.656619>> SOLVER >> f=inline('x*x*x-5*x+3'); >> x=fzero(f,0); >>x x= 0.6566 NEWTON RAPHSON ACCURACY %program for newton raphson method for accuracy f=inline('exp(x)*cos(x)-1.2'); df=inline('3*x*x+2*cos(x)*sin(x)'); ddf=inline('6*x+2*cos(x)*cos(x)-sin(x)*sin(x)'); x1=input('\n enter initial guess x1='); acc=input('\n enter accuracy acc='); y1=f(x1); y2=df(x1); y3=ddf(x1); a=(y1*y3)/(y2*y2); while(abs(a)>1) x1=input('\n enter initial guess x1=') y1=f(x1); y2=df(x1); y3=ddf(x1); a=(y1*y3)/(y2*y2); end while(abs(x2-x1)>acc) x2=x1-(y1/y2); x1=x2; y1=f(x1); y2=df(x1); end fprintf('\n the new root of equation=%f',x2); OUTPUT >>newtonaccuracy enter initial guess x1=0 enter accuracy acc=0.0001 the new root of equation=0.203087>> SOLVER >> f=inline('exp(x)*cos(x)-1.2'); >> x=fzero(f,1); >>x x= 0.203087 SUCCESSIVE APPROXIMATION ITERATION %program or succesive approximation by iteration g=inline('x-0.3*cos(x)-1'); dg=inline('-0.3*sin(x)'); x1=input('\n enter initial input x1='); n=input('\n enter no of iteration n='); a=dg(x1); while(abs(a)>1) x1=input('\n initial guess x1='); a=dg(x1); end for i=1:n x2=g(x1); x1=x2; end fprintf('\n the new root of eqation =%f',x2); OUTPUT >>successiveiteration enter initial input x1=0 enter no of iteration n=5 the new root of eqation =0.54407>> SOLVER >> f=inline('x-0.3*cos(x)-1'); >> x=fzero(f,1); >>x x= 0.54407 SUCCESSIVE APPROXIMATION ACCURACY %program or succesive approximation by accuracy g=inline('2*x-log(x)-7'); dg=inline('-0.3*sin(x)'); x1=input('\n enter initial input x1='); acc=input('\n enter accuracy acc='); a=dg(x1); while(abs(a)>1) x1=input('\n initial guess x1='); a=dg(x1); end x2=g(x1); while(abs(x1-x2)>acc) x2=g(x1); x1=x2; end fprintf('\n the new root of eqation =%d',x2); OUTPUT enter initial input x1=4 enter accuracy acc=0.0001 the new root of eqation =3.78928>> SOLVER >> f=inline('2*x-log(x)-7'); >> x=fzero(f,1) x= 3.789278 GAUSS ELIMINATION % gauss elimination programm n=input('\ no of elements='); for i=1:n for j=1:n ar(i,j)=input('\ enter no of matrix rowwise='); end end for i=1:n ar1(i)=input('\ enter constant'); end for q=1:n i=q; d=ar(i,i); for j=1:n ar(i,j)=ar(i,j)/d; end ar1(i)=ar1(i)/d; for i=q+1:n s=ar(i,q); for j=1:n ar(i,j)=ar(i,j)-s*ar(q,j); end ar1(i)=ar1(i)-s*ar1(q); end end disp(ar); a(n)=ar1(n); for w=n-1:-1:1 a(w)=ar1(w); for e=w:n-1 a(w)=a(w)-a(e+1)*ar(w,e+1); end end for j=1:n fprintf('\n the value x%d=%f',j,a(j)); end OUTPUT >>Gausseliminationmethod no of elements=3 enter no of matrix rowwise=2 enter no of matrix rowwise=-1 enter no of matrix rowwise=3 enter no of matrix rowwise=-4 enter no of matrix rowwise=-3 enter no of matrix rowwise=-2 enter no of matrix rowwise=3 enter no of matrix rowwise=1 enter no of matrix rowwise=-1 enter constant5 enter constant8 enter constant4 1.0000 -0.5 1.5 0 1.0000 8 0 0 1.0000 the value x1=2.895 the value x2=-0.20 the value x3=0.33>> SOLVER >> A=[2 -1 3; -4 -3 -2; 3 1 -1]; >> B=[5; 8; 4]; >> x=A\B x= 2.895 -0.20 0.33 GAUSS SEIDAL METHOD n=input('\n Enter Number of Equestion:'); for i=1:n for j=1:n ar(i,j)=input('\nEnter matrix elements row_wise :'); end end for i=1:n arl(i)=input('\nEnter second matrix elements :'); end n1=input('\nEnter number of iterations'); for i=1:n-1 for j=i+1:n if(abs(ar(i,i))<abs(ar(j,i))) for k=1:n temp=ar(i,k); ar(i,k)=ar(j,k); ar(j,k)=temp; temp=ar1(i); ar1(i)=ar1(j); ar1(j)=temp; end end end end for i=1:n x(i)=0; end for k=1:n1 for i=1:n const=ar(i); for j=1:n if(i~=j) const=const-(x(j)*ar(i,j)); end end x(i)=const/ar(i,i); fprintf('x%d=%f',i,x(i)); end fprintf('\n\n'); end OUTPUT >>gausssiedal Enter Number of Equestionn=3 Enter matrix elements row_wise 4 Enter matrix elements row_wise 1 Enter matrix elements row_wise 1 Enter matrix elements row_wise 1 Enter matrix elements row_wise 6 Enter matrix elements row_wise 2 Enter matrix elements row_wise -1 Enter matrix elements row_wise -2 Enter matrix elements row_wise -5 Enter second matrix elements 5 Enter second matrix elements 19 Enter second matrix elements 10 Enter number of iterations n1=6 x1=1.500000x2=0.750000x3=-1.600000 x1=1.712500x2=1.247917x3=-1.841667 x1=1.648437x2=1.339149x3=-1.865347 x1=1.631549x2=1.349857x3=-1.866253 x1=1.629099x2=1.350568x3=-1.866047 x1=1.628870x2=1.350537x3=-1.865989 SOLVER >> a=[4 1 1; 1 6 2; 1 -2 -5]; >> b=[5; 19; 10]; >> x=a\b x= 1.0762 4.1333 -3.4381 THOMAS ALGORITHM % program for tomas algorithm method n=input('\n enter no of elements n='); for i=1:n for j=1:n ar(i,j)=input('\n enter first matrix rowwise='); end end for i=1:n ar1=input('\n read constant matrix='); end for i=2:n d=ar(i,i-1)/ar(i-1,i-1); for j=1:n ar(i-1,j)=ar(i-1,j)*d; end ar1(i-1)=ar1(i-1)*d; for j=1:n ar(i,j)=ar(i,j)-ar(i-1,j); end ar1(i)=ar1(i)-ar1(i-1); end for i=1:n dig=ar(i,i); for j=1:n ar(i,j)=ar(i,j)/dig; end ar1(i)=ar1(i)/dig; end disp (ar); a(n)=ar1(n); for w=n-1:-1:1 a(w)=ar1(w); for e=w:n-1 a(w)=a(w)-a(e+1)*ar(w,e+1); end end for j=i:n fprintf('\n the values of variable x%d=%f',j,a(j)); end OUTPUT enter enter enter enter enter enter enter enter no of first first first first first first first elements n=4 matrix rowwise=2.04 matrix rowwise=-1 matrix rowwise=0 matrix rowwise=0 matrix rowwise=-1 matrix rowwise=2.04 matrix rowwise=-1 enter first matrix rowwise=0 enter first matrix rowwise=0 enter first matrix rowwise=-1 enter first matrix rowwise=2.04 enter first matrix rowwise=-1 enter first matrix rowwise=0 enter first matrix rowwise=0 enter first matrix rowwise=-1 enter first matrix rowwise=2.04 read constant matrix=40.8 read constant matrix=0.8 read constant matrix=0.8 read constant matrix=200.8 x1=65.9 x2=93.71 x3=124.49 x4=159.45 >> solver >> a=[2.04 -1 0 0;-1 2.04 -1 0;0 -1 2.04 -1;0 0 -1 2.04]; >> b=[40.8;0.8;0.8;200.8]; >> x=a\b x = 65.9 93.71 124.49 159.45 TRAPEZOIDAL f=inline('4*x+2'); x0=input('\n initial value of x0='); xn=input('\n final value of xn='); n=input('\n no of strips n='); h=(xn-x0)/n; ans=0; for i=1:n-1 ans=ans+f(x0+i*h); end ans=2*ans; ans1=f(x0)+f(xn); area=ans1+ans; area=(h/2)*area; fprintf('\n total area of strips =%f',area); OUTPUT initial value of x0=1 final value of xn=4 no of strips n=6 total area of strips =36.000000>> SOLVER >> Q=quadl('4*x+2',1,4); >> q Undefined function or variable 'q'. Did you mean: >> Q Q= 36 SIMPSONS 1/3RD % programme forsimpsons 1/3rd rule f=inline('exp(x)'); x0=input('\n initial value of x0='); xn=input('\n final value of xn='); n=input('\n no of strips n='); while (mod(n,2)~=0) n=input('\n no of strips again n='); end h=(xn-x0)/n; ans=0; for i=1:n-1 if (mod(i,2)~=0) ans=ans+4*(f(x0+i*h)); else ans=ans+2*f(x0+i*h); end end ans1=f(x0)+f(xn); area=ans+ans1; area=area*(h/3); fprintf('\n total area =%f',area); OUTPUT initial value of x0=0 final value of xn=4 no of strips n=4 total area =53.863846>> SOLVER >> Q=quadl('exp(x)',0,4); >> Q Q = 53.5982 SIMPSON 3/8th % programme forsimpsons 3/8th rule f=inline('4*x-1'); x0=input('\n initial value of x0='); xn=input('\n final value of xn='); n=input('\n no of strips n='); while (mod(n,3)~=0) n=input('\n no of strips again n='); end h=(xn-x0)/n; ans=0; for i=1:n-1 if (mod(i,3)~=0) ans=ans+3*(f(x0+i*h)); else ans=ans+2*f(x0+i*h); end end ans1=f(x0)+f(xn); area=ans+ans1; area=area*(3*h/8); fprintf('\n total area =%f',area); OUTPUT initial value of x0=1 final value of xn=4 no of strips n=6 total area =21.937500>> sampson38 initial value of x0=1 final value of xn=4 no of strips n=6 total area =27.000000>> SOLVER >> Q=quadl('4*x-1',1,4); >> Q Q= 27.0000 EULERS METHOD % flowchart for eulers method f=inline('y*x*x-1.1*y'); x0=input('\n enter initial value of x0='); y0=input('\n enter initial value of y0='); xg=input('\n enter final value of xg='); h=input('\n enter no of step size h='); n=(xg-x0)/h; for i=1:n yg=y0+h*f(x0,y0); x0=x0+h; yg=y0; end fprintf('\n the final value of yg=%f',yg); OUTPUT enter initial value of x0=0 enter initial value of y0=1 enter final value of xg=2 enter no of step size h=0.5 the final value of yg=1.000000>> SOLVER >> f=inline('y*x*x-1.1*y'); >> x0=0; >> xn=2; >> y0=1; >> h=0.5; >> xspan=[x0,h,xn]; >> [xe,ye]=ode45(f,xspan,y0); >> [xe,ye] ans = 0 1.0000 0.5000 0.6015 2.0000 1.5947 RK 4th ORDER % flow chart for runge kutta 4 order method f=inline('sqrt(x*x+y)'); x0=input('\n enter initial value of xo='); y0=input('\n enter initial value of y0='); xg=input('\n enter final value of xg='); h=input('\n enter the step size='); n=(xg-x0)/h; for i=1:n k1=h*f(x0,y0); k2=h*f(x0+h/2,y0+k1/2); k3=h*f(x0+h/2,y0+k2/2); k4=h*f(x0+h,y0+k3); k=(k1+2*k2+2*k3+k4)/6; yg=y0+k; x0=x0+h; y0=yg; end fprintf('\n the final value of yg=%f',yg); OUTPUT >> rk4order enter initial value of xo=0 enter initial value of y0=1 enter final value of xg=0.4 enter the step size=0.2 the final value of yg=1.449537>> SOLVER >> f=inline('sqrt(x*x+y)'); >> x0=0; >> xn=0.4; >> y0=1; >> h=0.2; >> xspan=[x0,h,xn]; >> [xe,ye]=ode45(f,xspan,y0); >> [xe,ye] ans = 0 1.0000 0.2000 1.2113 0.4000 1.4495 RK 2 SIMULTANEOUS EQUATION % flow chart for runge kutta 4 order method f=inline('0*x+0*y+z'); g=inline('(9+3*x*z-9*y)/2'); x0=input('\n enter initial value of xo='); y0=input('\n enter initial value of y0='); z0=input('\n enter value of z0='); xg=input('\n enter final value of xg='); h=input('\n enter the step size='); n=(xg-x0)/h; for i=1:n k1=h*f(x0,y0,z0); l1=h*g(x0,y0,z0); k2=h*f(x0+h,y0+k1,z0+l1); l2=h*g(x0+h,y0+k1,z0+l1); k=(k1+k2)/2; l=(l1+l2)/2; yg=y0+k; zg=z0+l; y0=yg; z0=zg end fprintf('\n the final value of yg=%f',yg); fprintf('\n the final value of zg=%f',zg); OUTPUT enter initial value of xo=0 enter initial value of y0=1 enter value of z0=-2 enter final value of xg=0.1 enter the step size=0.1 z0 = -1.9700 the final value of yg=0.800000 the final value of zg=-1.970000>> MINIMIZATION >> f=[2 3]; >> a=[-2 -4; -4 -2]; >> b=[-80;-100]; >>lb=[0,0]; >> [X,val]=linprog(f,a,b,[],[],lb) Optimization terminated. X= 20.0000 10.0000 val = 70.0000 LAPLACE EQUATION % profram for laplace eq tu=input('\n enter upward boundary value tu='); td=input('\n enter downward boundary value td='); tl=input('\n enter leftside boundary value tl='); tr=input('\n enter rightside boundary value tr='); a=[4 -1 -1 0; -1 4 0 -1; -1 0 4 -1; 0 -1 -1 4]; b(1,1)=tl+tu; b(2,1)=tr+tu; b(3,1)=tl+td; b(4,1)=tr+td; v=linsolve(a,b); fprintf('\n result=\n'); for i=1:4 fprintf('\n temp %d:%0.4f',i,v(i)); end OUTPUT enter upward boundary value tu=2000 enter downward boundary value td=500 enter leftside boundary value tl=1000 enter rightside boundary value tr=0 result= temp 1:1187.5000 temp 2:937.5000 temp 3:812.5000 temp 4:562.5000>> Straight line % program for straight line equation n=input('\n no of functions n='); for i=1:n x(i)=input('\n take functions of x(i)='); y(i)=input('\n take functions of y(i)='); end s0=0; s1=0; s2=0; s3=0; for i=1:n s0=s0+x(i); s1=s1+y(i); s2=s2+x(i)*y(i); s3=s3+x(i)*x(i); end d=s0*s0-n*s3; da=s1*s0-n*s2; db=s0*s2-s1*s3; a=da/d; b=db/d; fprintf('\n print value of a=%f',a); fprintf('\n print value of b=%f',b); fprintf('\n print straiht line equation=%fx+%f',a,b); OUTPUT > straightline no of functions n=4 take functions of x(i)=0 take functions of y(i)=1.80 take functions of x(i)=5 take functions of y(i)=1.45 take functions of x(i)=10 take functions of y(i)=1.18 take functions of x(i)=15 take functions of y(i)=1 print value of a=-0.053400 print value of b=1.758000 print straiht line equation=-0.053400x+1.758000>> solver >> x=[0 5 10 15]; >> y=[1.80 1.45 1.18 1]; >> z=polyfit(x,y,1); >> a=z(1); >> b=z(2); >> a a= -0.0534 >> b b= 1.7580 POWER EQUATION (a*bx) % program for straight line equation n=input('\n no of functions n='); for i=1:n x(i)=input('\n take functions of x(i)='); y(i)=input('\n take functions of y(i)='); Y(i)=log(y(i)); X(i)=log(x(i)); end s0=0; s1=0; s2=0; s3=0; for i=1:n s0=s0+X(i); s1=s1+Y(i); s2=s2+X(i)*Y(i); s3=s3+X(i)*X(i); end d=s0*s0-n*s3; da=s1*s0-n*s2; db=s0*s2-s1*s3; A=da/d; B=db/d; fprintf('\n print value of A=%f',A); fprintf('\n print value of B=%f',B); a=exp(A); b=B; fprintf('\n print straiht line equation=%f*%f^x',a,b); OUTPUT no of functions n=7 enter value of x=0 enter value of y=32 enter value of x=1 enter value of y=47 enter value of x=2 enter value of y=65 enter value of x=3 enter value of y=92 enter value of x=4 enter value of y=132 enter value of x=5 enter value of y=190 enter value of x=6 enter value of y=275 print value of A=0.089099 print value of B=5.094962 print straiht line equation=1.227719*124440.513758^x>> SOLVER >> x=[0 1 2 3 4 5 6]; >> y=[32 47 65 92 132 190 275]; >> z=polyfit(x,y,1); >> a=z(1); >> b=z(2); >> a a= 38.6429 >> s Undefined function or variable 's'. >> b b= 3.0714 Power equation (axb) % program for straight line equation n=input('\n no of functions n='); for i=1:n x(i)=input('\n take functions of x(i)='); y(i)=input('\n take functions of y(i)='); Y(i)=log(y(i)); X(i)=log(x(i)); end s0=0; s1=0; s2=0; s3=0; for i=1:n s0=s0+X(i); s1=s1+Y(i); s2=s2+X(i)*Y(i); s3=s3+X(i)*X(i); end d=s0*s0-n*s3; da=s1*s0-n*s2; db=s0*s2-s1*s3; A=da/d; B=db/d; fprintf('\n print value of A=%f',A); fprintf('\n print value of B=%f',B); a=exp(B); b=A; fprintf('\n print straiht line equation=%f*x^%f',a,b); OUTPUT no of functions n=4 take functions of x(i)=900 take functions of y(i)=89 take functions of x(i)=1500 take functions of y(i)=110 take functions of x(i)=2700 take functions of y(i)=120 take functions of x(i)=3000 take functions of y(i)=125 print value of A=0.263566 print value of B=2.722970 print straiht line equation=15.225467*x^0.263566>> power2 SOLVER >> x=[900 1500 2700 3000]; >> y=[89 110 120 125]; >> z=polyfit(x,y,2); >> a=z(1); >> b=z(2); >> a a= -9.6831e-06 >> b b= 0.0534 QUADRATIC EQUATION %program for qudratic equation n=input ('\n enter the no of elements='); for i=1:n x(i)=input('\n enter the values of x='); y(i)=input('\n enter the values of y='); end S0=0; S1=0; S2=0; S3=0; S4=0; S5=0; S6=0; for i=1:n S0=S0+x(i); S1=S1+y(i); S2=S2+x(i)*y(i); S3=S3+x(i)*x(i); S4=S4+x(i)*x(i)*y(i); S5=S5+x(i)*x(i)*x(i); S6=S6+x(i)*x(i)*x(i)*x(i); end a=[S3 S0 n; S5 S3 S0; S6 S5 S3;]; b=[S1;S2;S4;]; v=linsolve(a,b); fprintf('a=%f b=%f c=%f',v(1),v(2),v(3)); fprintf('\n\t y=%f^2+%f*x+%f',v(1),v(2),v(3)); OUTPUT >> qudraticequation enter the no of elements=5 enter the values of x=0.1 enter the values of y=1.4 enter the values of x=0.2 enter the values of y=1.56 enter the values of x=0.3 enter the values of y=1.76 enter the values of x=0.4 enter the values of y=2 enter the values of x=0.5 enter the values of y=2.28 a=2.000000 b=1.000000 c=1.280000 y=2.000000^2+1.000000*x+1.280000>> SOLVER >> x=[10 12 15 23 20 80]; >> y=[14 17 23 25 21 100]; >> z=polyfit(x,y,2); >> a=z(1); >> b=z(2); >> c=z(3); >> a a= 0.0084 >> b b= 0.4485 >> c c= 10.4871 EXPONENTIAL %program for power equation (y=a*e^(bx)) n=input ('\n enter the no of elements='); for i=1:n x(i)=input('\n enter the values of x='); temp=input('\n enter the values of y='); y(i)=log(temp); end S0=0; S1=0; S2=0; S3=0; for i=1:n S0=S0+x(i); S1=S1+y(i); S2=S2+x(i)*y(i); S3=S3+x(i)*x(i); end d=S0*S0-n*S3; da=S1*S0-n*S2; db=S0*S2-S1*S3; a1=da/d; b1=db/d; b=(a1); a=exp(b1); fprintf('\n y=(%f)e^(%f)x',a,b); OUTPUT >> powerequationforyaebx enter the no of elements=4 enter the values of x=2 enter the values of y=25 enter the values of x=4 enter the values of y=38 enter the values of x=6 enter the values of y=56 enter the values of x=8 enter the values of y=84 y=(16.814818)e^(0.201179)x>> SOLVER >> x=[10 12 15 23 20 80]; >> y=[14 17 23 25 21 100]; >> z=polyfit(x,y,2); >> a=z(1); >> b=z(2); >> c=z(3); >> a a= 0.0084 >> b b= 0.4485 >> c c= 10.4871 LAGRANGES INTERPOLATION % program for lagranges interpolation n=input('enter the values of n='); for i = 1:n x(i)=input('enter the values of x='); y(i)=input('enter the values of y='); end xg=input('enter the values of xg='); yg=0; for j = 1:n nu=1; de=1; for i =1:n if(i~=j) nu= nu*(xg-x(i)); de=de*(x(j)-x(i)); end end l(j)=nu/de; yg=yg+l(j)*y(j); fprintf('\n value of yg=%f',yg); end OUTPUT >> langranges enter the values of n=5 enter the values of x=5 enter the values of y=150 enter the values of x=7 enter the values of y=392 enter the values of x=11 enter the values of y=1452 enter the values of x=13 enter the values of y=2366 enter the values of x=17 enter the values of y=5202 enter the values of xg=9 value of yg=-16.666667 value of yg=192.400000 value of yg=1483.066667 value of yg=694.400000 value of yg=810.000000>> SOLVER >> x=[5 7 11 13 17]; >> y=[150 392 1452 2366 5202]; >> yg=interp1(x,y,9) yg = 922 NEWTON FORWARD n=input('\n enter no of elements n='); for i=1:n x(i)=input('\n enter value of x='); y(i,1)=input('\n enter of value y='); end xg=input('\n enter value of xg='); h=x(2)-x(1); c=n-1; for j=2:n c=c-1; for i=1:c+1 y(i,j)=y(i+1,j-1)-y(i,j-1); end end c=n; for i=1:n-1 fprintf('\n\n'); c=c-1; for j=2:c+1 fprintf('\nt %f',y(i,j)); end end u=(xg-x(1))/h; ans=y(1,1)+u*y(1,2); yg=0; m=2; u1=u; for k=3:n if (m<k) u=u*(u1-(m-1)); end fact=1; for i=1:k-1 fact=fact*i; end yg=yg+((u/fact)*y(1,k)); m=m+1; end yg=ans+yg; fprintf('\n final value of yg=%f',yg); OUTPUT >> newtonsforward enter no of elements n=5 enter value of x=0 enter of value y=5 enter value of x=2 enter of value y=29 enter value of x=4 enter of value y=125 enter value of x=6 enter of value y=341 enter value of x=8 enter of value y=725 enter value of xg=1.5 t 24.000000 t 72.000000 t 48.000000 t 0.000000 t 96.000000 t 120.000000 t 48.000000 t 216.000000 t 168.000000 t 384.000000 final value of yg=18.125000>> SOLVER final value of yg=18.125000>> >> >> x=[0 2 4 6 8]; >> y=[5 29 125 341 725]; >> yg=interp1(x,y,1.5) yg = 23 INVERSE INTERPOLATION % program for inverse lagranges interpolation n=input('enter the values of n='); for i = 1:n x(i)=input('enter the values of x='); y(i)=input('enter the values of y='); end yg=input('enter the values of yg='); xg=0; for j = 1:n nu=1; de=1; for i =1:n if(i~=j) nu= nu*(yg-y(i)); de=de*(y(j)-y(i)); end end l(j)=nu/de; xg=xg+l(j)*x(j); fprintf('\n value of xg=%f',xg); end OUTPUT >> inverselangranges enter the values of n=4 enter the values of x=20 enter the values of y=0.342 enter the values of x=25 enter the values of y=0.423 enter the values of x=30 enter the values of y=0.5 enter the values of x=35 enter the values of y=0.65 enter the values of yg=0.390 value of xg=4.788695 value of xg=29.029424 value of xg=22.259080 value of xg=22.840578>> SOLVER >> y=[0.342 0.423 0.5 0.65]; >> x=[20 25 30 35]; >> xg=interp1(y,x,0.396) xg =23.3333