How to create array while using integral function?

Question

Ishani Prachchhak 2023-4-24

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1952298-how-to-create-array-while-using-integral-function

编辑： VBBV 2023-4-24

Following is the code, there are parameters - b,c,gama1,sigma. And r that is the radius of the sphere is varing, also the time is varying. I want to get at each radial point at given time the value of I(integral) What am I doing is wrong?

K1=6;%(W/m.K)Thermal conductivity of Fe3O4 nanoparticle
K2=0.598; %Thermal conductivity of water-https://thermtest.se/thermal-conductivity-of-water
k1= 1.82E-06; %(m^2/s) Diffusivity of Fe3O4 nanoparticle
k2=2.29e-9; %at 25C (m^2/s) diffusivity of water- https://en.wikipedia.org/wiki/Molecular_diffusion
a=15e-9; %radius of nanoparticle
Vol= (4/3)*3.14*a^3;%Volume of nanoparticle
A=8.68E-05; %(W)heatproduced/ unit volume
b=(K2/K1)*((k1/k2)^1/2);
r=linspace(15e-9,17e-9,10);
c=1-(K2/K1);
t=linspace(1e-12,100e-12,10);
gama1=(a^2)/k1;
sigma=((r/a)-1)*((k1/k2)^1/2);
for t = 1e-12:100e-12
    r = 15e-9:17e-9;
    fun = @(y,gama1,sigma,b,c,t) ((exp(((-y.^2).*t)./gama1)).*(sin(y)-(y.*cos(y))).*((b.*y.*sin(y).*cos(sigma.*y))-((c.*sin(y)-y.*cos(y)).*sin(sigma.*y))))./((y.^3).*((((c.*sin(y))-(y.*cos(y))).^2)+((b.^2).*(y.^2).*(sin(y).^2))));
    I=integral(@(y) fun(y,gama1,sigma,b,c,t),0,inf); %integration wrt y with other constants
end

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

VBBV 2023-4-24

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1952298-how-to-create-array-while-using-integral-function#answer_1222138

编辑：VBBV 2023-4-24

在 MATLAB Online 中打开

K1=6;%(W/m.K)Thermal conductivity of Fe3O4 nanoparticle

K2=0.598; %Thermal conductivity of water-https://thermtest.se/thermal-conductivity-of-water

k1= 1.82E-06; %(m^2/s) Diffusivity of Fe3O4 nanoparticle

k2=2.29e-9; %at 25C (m^2/s) diffusivity of water- https://en.wikipedia.org/wiki/Molecular_diffusion

a=15e-9; %radius of nanoparticle

Vol= (4/3)*3.14*a^3;%Volume of nanoparticle

A=8.68E-05; %(W)heatproduced/ unit volume

b=(K2/K1)*((k1/k2)^1/2);

r=linspace(15e-9,17e-9,10);

c=1-(K2/K1);

t=linspace(1e-12,100e-12,10);

gama1=(a^2)/k1;

sigma=((r/a)-1)*((k1/k2)^1/2);

syms y

for J = 1:length(sigma)

for K = 1:length(t)

fun = ((exp(((-y.^2).*t(K))./gama1)).*(sin(y)-(y.*cos(y))).*((b.*y.*sin(y).*cos(sigma(J).*y))-((c.*sin(y)-y.*cos(y)).*sin(sigma(J).*y))))./((y.^3).*((((c.*sin(y))-(y.*cos(y))).^2)+((b.^2).*(y.^2).*(sin(y).^2))));

I(K,J)= vpaintegral(fun,y,[0,Inf]); %integration wrt y with other constants

end

I = (vpa(I,15))

I =

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

Answer 2

Dyuman Joshi 2023-4-24

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1952298-how-to-create-array-while-using-integral-function#answer_1222143

在 MATLAB Online 中打开

%Formatting your code properly is a good coding practice
K1=6;                   %(W/m.K)Thermal conductivity of Fe3O4 nanoparticle
K2=0.598;               %Thermal conductivity of water-https://thermtest.se/thermal-conductivity-of-water
k1=1.82E-06;            %(m^2/s) Diffusivity of Fe3O4 nanoparticle
k2=2.29e-9;             %at 25C (m^2/s) diffusivity of water- https://en.wikipedia.org/wiki/Molecular_diffusion
a=15e-9;                %radius of nanoparticle
Vol=(4/3)*3.14*a^3;     %Volume of nanoparticle
A=8.68E-05;             %(W)heatproduced/ unit volume
b=(K2/K1)*((k1/k2)^1/2);
r=linspace(15e-9,17e-9,10);
c=1-(K2/K1);
t=linspace(1e-12,100e-12,10);
gama1=(a^2)/k1;
sigma=((r/a)-1)*((k1/k2)^1/2);
%preallocation
I = zeros(numel(t),numel(r));
%Function to integrate
fun = @(y,t) ((exp(((-y.^2).*t)./gama1)).*(sin(y)-(y.*cos(y))).*((b.*y.*sin(y).*cos(sigma.*y))-((c.*sin(y)-y.*cos(y)).*sin(sigma.*y))))./((y.^3).*((((c.*sin(y))-(y.*cos(y))).^2)+((b.^2).*(y.^2).*(sin(y).^2))));
for k = 1:numel(t)
    %Pass the value of t(k) 
    I(k,:)=integral(@(y) fun(y,t(k)),0,inf,'ArrayValued',true); %integration wrt y with other constants
end
format long
I
I = 10×10
   5.253204730589755   5.253496876204714   5.253496836492238   5.253496764345236   5.253496718036804   5.253496699699072   5.253496651746186   5.253496649534816   5.253496645563740   5.253496581295285
   5.250606466445789   5.253496875856392   5.253496824734424   5.253496798055983   5.253496781958984   5.253496757830739   5.253496678522883   5.253496630996006   5.253496573923628   5.253496627903624
   5.248595986052435   5.253496881251547   5.253496844173969   5.253496807104954   5.253496770028961   5.253496733075693   5.253496695949829   5.253496658502814   5.253496621075591   5.253496585141805
   5.246968241707677   5.253496883582442   5.253496838807810   5.253496794002702   5.253496781377496   5.253496746044602   5.253496684327441   5.253496648018087   5.253496617617959   5.253496636420552
   5.245609714553339   5.253496881329098   5.253496844030694   5.253496806559629   5.253496770556284   5.253496733477224   5.253496695275669   5.253496658419976   5.253496621098609   5.253496589641397
   5.244440063530290   5.253496881255291   5.253496844177262   5.253496807084363   5.253496770061161   5.253496732984319   5.253496695855780   5.253496658813329   5.253496621616801   5.253496585266910
   5.243405230465747   5.253496881237234   5.253496844179250   5.253496807104066   5.253496770097128   5.253496736876893   5.253496707832046   5.253496604517689   5.253496711479302   5.253496482981266
   5.242469707085853   5.253496881055251   5.253496844180170   5.253496807106646   5.253496770015861   5.253496733667430   5.253496699741413   5.253496643310109   5.253496648326808   5.253496553328025
   5.241609991854334   5.253496879830237   5.253496844180530   5.253496807107732   5.253496770024883   5.253496733066472   5.253496697085797   5.253496654382595   5.253496629636052   5.253496574988831
   5.240810143920073   5.253496874524455   5.253496844297906   5.253496807278024   5.253496770244370   5.253496733202896   5.253496696472889   5.253496657718357   5.253496624161022   5.253496581597618