```Date: Jan 26, 2013 6:53 AM
Author: maia
Subject: use quadl and give me this error=??? Undefined function or method 'isfinite

i m new to matlab and i want plot these equationunfortunately when i write following code it give me error??? Undefined function or method 'isfinite' for input arguments of type 'sym'.Error in ==> quadl at 74if ~isfinite(y(1))Error in ==> test10 at 84ss=quadl(f , 1 , 2);i need to run this code successfully in 1 day please if you know anything that can help me let me knowhere is my code and thank you in advanceclose allclear clcre=0.5;t=0:1:10;syms k r n  zs=k*r;m=k*re;eps=70/9600;%*************************************%for n=0%*************************************pin0= besseli(1,k*r);pin01=besselk(1,k);pin04=pin0*pin01;pin02=((1-eps)*besseli(0,k)*besselk(0,k)*diff(besselk(0,k)));pin03=1/(eps*diff(besselk(0,k))*besseli(0,k)-besselk(0,k)*diff(besseli(0,k)));pin07=pin03*pin02;pin08=pin04*pin07;%ezplot(pin08);%*************************************%for n=1%*************************************pin1= besseli(1,k*r);pin11=besselk(1,k);pin14=pin1*pin11;pin12=((1-eps)*besseli(1,k)*besselk(1,k)*diff(besselk(1,k)));pin13=1/(eps*diff(besselk(1,k))*besseli(1,k)-besselk(1,k)*diff(besseli(1,k)));pin17=pin13*pin12;pin18=2*pin14*pin17;pin19=cos(t);pin10=pin18*pin19;%ezplot(pin10);%*************************************%for n=2%*************************************pin2= besseli(2,k*r);pin21=besselk(2,k);pin24=pin2*pin21;pin22=((1-eps)*besseli(2,k)*besselk(2,k)*diff(besselk(2,k)));pin23=1/(eps*diff(besselk(2,k))*besseli(2,k)-besselk(2,k)*diff(besseli(2,k)));pin27=pin23*pin22;pin28=2*pin24*pin27;% pin9=cos(t);% pin10=pin8*pin9;%ezplot(pin27);%*************************************%for n=3%*************************************pin3= besseli(3,k*r);pin31=besselk(3,k);pin34=pin3*pin31;pin32=((1-eps)*besseli(3,k)*besselk(3,k)*diff(besselk(3,k)));pin33=1/(eps*diff(besselk(3,k))*besseli(3,k)-besselk(3,k)*diff(besseli(3,k)));pin37=pin33*pin32;pin38=2*pin34*pin37;% pin9=cos(t);% pin10=pin8*pin9;%ezplot(pin37);%*************************************%for n=4%*************************************pin4= besseli(4,k*r);pin41=besselk(4,k);pin44=pin4*pin41;pin42=((1-eps)*besseli(4,m)*besselk(4,k)*diff(besselk(4,k)));pin43=1/(eps*diff(besselk(4,k))*besseli(4,k)-besselk(4,k)*diff(besseli(4,k)));pin47=pin43*pin42;pin48=2*pin44*pin47;%pin9=cos(t);%pin10=pin8*pin9;%ezplot(pin47); sigma=pin48*cos(4*t)+pin38*cos(3*t)+pin28*cos(2*t)+pin18*cos(t)+pin08;f = @(k , r )sigma; ss=quadl(f , 1 , 2);--------------------------------------
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