How to get a column vector for all the considered time instants?

1 次查看(过去 30 天)
Hi everyone. I have a problem with this code. At the end I would like to obtain the r_ORF column vector for all the time instants (41) but I don't understand why this does not happen in this code. Thanks in advance.
clc;clear all; close all;
% Components determination in ORF
% ECI (GEOC) to ORF matrix determination
A = load('DatiCosmoSkymed.txt');
times = A(:,1);
for i = 1: length(times)
r_inertial(1,i)= A(i,8);
r_inertial(2,i)= A(i,9);
r_inertial(3,i)= A(i,10);
v_inertial(1,i)= A(i,11);
v_inertial(2,i)= A(i,12);
v_inertial(3,i)= A(i,13);
kORF_ECI=-r_inertial/norm(r_inertial);
jORF_ECI=-cross(r_inertial,v_inertial)/norm(cross(r_inertial,v_inertial));
iORF_ECI=cross(jORF_ECI,kORF_ECI);
M_ECItoORF(1,1)=iORF_ECI(1,1);
M_ECItoORF(1,2)=iORF_ECI(2,1);
M_ECItoORF(1,3)=iORF_ECI(3,1);
M_ECItoORF(2,1)=jORF_ECI(1,1);
M_ECItoORF(2,2)=jORF_ECI(2,1);
M_ECItoORF(2,3)=jORF_ECI(3,1);
M_ECItoORF(3,1)=kORF_ECI(1,1);
M_ECItoORF(3,2)=kORF_ECI(2,1);
M_ECItoORF(3,3)=kORF_ECI(3,1);
r_ECI = r_inertial;
r_ORF = M_ECItoORF*r_ECI;
display(r_ORF)
end

采纳的回答

Walter Roberson
Walter Roberson 2021-10-11
% Components determination in ORF
% ECI (GEOC) to ORF matrix determination
A = load('DatiCosmoSkymed.txt');
times = A(:,1);
num_times = size(times,1);
r_ORDF = cell(num_times,1);
for i = 1: num_times
r_inertial(1,i)= A(i,8);
r_inertial(2,i)= A(i,9);
r_inertial(3,i)= A(i,10);
v_inertial(1,i)= A(i,11);
v_inertial(2,i)= A(i,12);
v_inertial(3,i)= A(i,13);
kORF_ECI=-r_inertial/norm(r_inertial);
jORF_ECI=-cross(r_inertial,v_inertial)/norm(cross(r_inertial,v_inertial));
iORF_ECI=cross(jORF_ECI,kORF_ECI);
M_ECItoORF(1,1)=iORF_ECI(1,1);
M_ECItoORF(1,2)=iORF_ECI(2,1);
M_ECItoORF(1,3)=iORF_ECI(3,1);
M_ECItoORF(2,1)=jORF_ECI(1,1);
M_ECItoORF(2,2)=jORF_ECI(2,1);
M_ECItoORF(2,3)=jORF_ECI(3,1);
M_ECItoORF(3,1)=kORF_ECI(1,1);
M_ECItoORF(3,2)=kORF_ECI(2,1);
M_ECItoORF(3,3)=kORF_ECI(3,1);
r_ECI = r_inertial;
r_ORF{i} = M_ECItoORF*r_ECI;
end
I think you should reconsider your code a bit.
The first iteration, you write to the first column of r_inertial, so r_intertial is 3 x 1. M_ECItoORF is 3 x 3. In the calculation of r_ORF you use the * operator between the 3 x 3 M_ECItoORF and the 3 x 1 R_ECI to get a 3 x 1 result the first iteration.
The second iteration, you write to the second column of r_interial, so r_inertial is 3 x 2. And for kORF_ECI and jORF_ECI you use that entire 3 x 2 r_intertial . Are you certain that you want to be using the cumulative r_intertial in the calculation, not just the "current" column of r_intertial ?
Then you get down to the r_ORF, M_ECI is still 3 x 3, r_ECI is now 3 x 2 because it is is the 3 x 2 r_inertial, so r_ORF becomes 3 x 2, not 3 x 1.
And so on, until you get to the end, and the last r_ORF is 3 x number_of_times .
Does this make sense to do ???
  3 个评论
Loren99
Loren99 2021-10-12
At the end I would like to diplay on the command window r_ORF as 3x1 column vectors for each time instant analyzed
Walter Roberson
Walter Roberson 2021-10-12
% Components determination in ORF
% ECI (GEOC) to ORF matrix determination
A = load('DatiCosmoSkymed.txt');
times = A(:,1);
num_times = size(times,1);
r_ORDF = zeros(3, num_times);
for i = 1: num_times
r_inertial(1,1)= A(i,8);
r_inertial(2,1)= A(i,9);
r_inertial(3,1)= A(i,10);
v_inertial(1,1)= A(i,11);
v_inertial(2,1)= A(i,12);
v_inertial(3,1)= A(i,13);
kORF_ECI=-r_inertial/norm(r_inertial);
jORF_ECI=-cross(r_inertial,v_inertial)/norm(cross(r_inertial,v_inertial));
iORF_ECI=cross(jORF_ECI,kORF_ECI);
M_ECItoORF(1,1)=iORF_ECI(1,1);
M_ECItoORF(1,2)=iORF_ECI(2,1);
M_ECItoORF(1,3)=iORF_ECI(3,1);
M_ECItoORF(2,1)=jORF_ECI(1,1);
M_ECItoORF(2,2)=jORF_ECI(2,1);
M_ECItoORF(2,3)=jORF_ECI(3,1);
M_ECItoORF(3,1)=kORF_ECI(1,1);
M_ECItoORF(3,2)=kORF_ECI(2,1);
M_ECItoORF(3,3)=kORF_ECI(3,1);
r_ECI = r_inertial;
r_ORF(:,i) = M_ECItoORF*r_ECI;
end
I believe that should give you a 3 x (number of times) array

请先登录,再进行评论。

更多回答(0 个)

类别

Help CenterFile Exchange 中查找有关 Data Import and Analysis 的更多信息

产品


版本

R2021b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by