I am trying to import excel windspeed data and to multiply each table variables with the vectors within the for loop, how to change for table variables into vector form?

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Tzu-Tung Chen
Tzu-Tung Chen 2023-5-23
回答： Sugandhi 2023-6-7
clc; clear all; close all;
% Input data;
g = 9.81;
fs = 0.000003;
w_data = readtable("LakeTahoe_v2_wind_velocity_test.xlsx","ReadVariableNames",true);
%w_data only shows 11.2, 8.0, and 8.1
fi=0.001;
fb=0.05;
rdd=0.005;
ev=20.0;
huo=10.0;
hbo=10.0;
Dx=200.0;
Dt=10.0;
nx=50.0;
nt=103680.0;
% Initial conditions;
for k=1:nx-1
hu(k)=huo;
hb(k)=hbo;
hun(k)=huo;
hbn(k)=hbo;
end
for k1=1:nx
zb(k1)=0;
uu(k1)=0;
ub(k1)=0;
uun(k1)=0;
ubn(k1)=0;
end
%I thought about adding another for loop here to run the main program below with the three different answers above
for i=1:nt
% Continuity equation for the upper fluid layer;
for j=2:nx-2
qul(j)=uu(j)*(hu(j)+hu(j-1))/2;
qur(j)=uu(j+1)*(hu(j)+hu(j+1))/2;
hun(j)=hu(j)-(Dt/Dx)*(qur(j)-qul(j));
end
% Continuity equation for the lower fluid layer;
for j=2:nx-2
qbl(j)=ub(j)*(hb(j)+hb(j-1))/2;
qbr(j)=ub(j+1)*(hb(j)+hb(j+1))/2;
hbn(j)=hb(j)-(Dt/Dx)*(qbr(j)-qbl(j));
end
% Updating of layer depth values;
for j=2:nx-2
hu(j)=hun(j);
hb(j)=hbn(j);
end
% Force equilibrium equation for the upper layer;
for j=3:nx-2
hum(j)=(hu(j)+hu(j-1))/2;
ts(j)=fs*w.*abs(w)/hum(j); %wind velocity is here
ti(j)=fi*(uu(j)-ub(j))*abs(uu(j)-ub(j))/hum(j);
ed(j)=ev*(uu(j-1)-2*uu(j)+uu(j+1))/Dx^2;
uun(j)=uu(j)-Dt*g*(hu(j)+hb(j)+zb(j)-hu(j-1)-hb(j-1)-zb(j-1))/Dx+Dt*(ed(j)+ts(j)-ti(j));
end
% Force equilibrium equation for the lower layer;
for j=3:nx-2
hbm(j)=(hb(j)+hb(j-1))/2;
ti(j)=fi*(uu(j)-ub(j))*abs(uu(j)-ub(j))/hbm(j);
tb(j)=fb*ub(j)*abs(ub(j))/hbm(j);
ed(j)=ev*(ub(j-1)-2*ub(j)+ub(j+1))/Dx^2;
ubn(j)=ub(j)-Dt*g*((hu(j)+hb(j)+zb(j)-hu(j-1)-hb(j-1)-zb(j-1))/Dx-rdd*(hu(j)-hu(j-1))/Dx)+Dt*(ed(j)+ti(j)-tb(j));
end
% Updating of fluid velocity values;
for j=3:nx-2
uu(j)=uun(j);
ub(j)=ubn(j);
Hbfinal(j)=hbn(j);
Htotal(j)=hun(j)+hbn(j);
end
Eu=0;
El=0;
for j=3:nx-2
Eu=Eu+(hu(j)+hu(j-1))/2*uu(j)^2;
El=El+(hb(j)+hb(j-1))/2*ub(j)^2;
end
Hupper(i)=hu(nx-2);
Hlower(i)=hb(nx-2);
end
  1 个评论
KSSV
KSSV 2023-5-23
The below lines:
for k=1:nx-1
hu(k)=huo;
hb(k)=hbo;
hun(k)=huo;
hbn(k)=hbo;
end
for k1=1:nx
zb(k1)=0;
uu(k1)=0;
ub(k1)=0;
uun(k1)=0;
ubn(k1)=0;
end
can be simply replaced by:
hu=huo*ones(1,nx-1);
hb=hbo*ones(1,nx-1);;
hun=huo*ones(1,nx-1);;
hbn=hbo*ones(1,nx-1);;
zb=zeros(1,nx) ;
uu=zeros(1,nx) ;
ub=zeros(1,nx) ;
uun=zeros(1,nx) ;
ubn=zeros(1,nx) ;

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回答（1 个）

Sugandhi
Sugandhi 2023-6-7
Ran in:
Hi,
I understand that you want to convert table variables to vector form.
In MATLAB, you can convert a table variable to a vector using the table2array and reshape functions. Here's an example:
% Create a sample table
T = table(rand(3,1), rand(3,1), rand(3,1), 'VariableNames', {'Var1', 'Var2', 'Var3'})
T = 3×3 table
Var1 Var2 Var3 _______ _______ _______ 0.74342 0.76146 0.16319 0.54526 0.36217 0.86704 0.88032 0.22428 0.99576
% Convert table to a numerical array
A = table2array(T)
A = 3×3
0.7434 0.7615 0.1632 0.5453 0.3622 0.8670 0.8803 0.2243 0.9958
% Reshape array to column vector
v = reshape(A, numel(A), 1)
v = 9×1
0.7434 0.5453 0.8803 0.7615 0.3622 0.2243 0.1632 0.8670 0.9958
In the code above, the `table` function is used to create a sample table with 3 rows and 3 variables. The `table2array` function is used to convert the table to a numerical array. The `reshape` function is then used to convert the array into a column vector.
For more understanding, kindly go through following links:

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