I need help to figure out why these variables aren't being found.

Question

DJ V 2024-10-16

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2160235-i-need-help-to-figure-out-why-these-variables-aren-t-being-found

移动：Voss 2024-10-22

I have written simulink code that is to produce variables that later are to be read into Matlab. Unfortunately, Matlab interprets those variables using the following errors:

>> EqnsOfMotionback

Warning: Variable 'pn' not found.

> In EqnsOfMotionback (line 95)

Warning: Variable 'pe' not found.

> In EqnsOfMotionback (line 96)

Warning: Variable 'pd' not found.

> In EqnsOfMotionback (line 97)

Warning: Variable 'phi' not found.

> In EqnsOfMotionback (line 98)

Warning: Variable 'psi' not found.

> In EqnsOfMotionback (line 99)

Warning: Variable 'theta' not found.

> In EqnsOfMotionback (line 100)

Why are all these variables not being found? I put them in a specific directory on purpose. I don't want to leave it to a computer's whim or some vaguely known "rule".

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

Walter Roberson 2024-10-16

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2160235-i-need-help-to-figure-out-why-these-variables-aren-t-being-found#answer_1533035

在 MATLAB Online 中打开

load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pn.mat","pn");
load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pe.mat","pe");
load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pd.mat","pd");
load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\phi.mat","phi");
load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\psi.mat","psi");
load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\theta.mat","theta");

The warning messages are telling you that pn is not being found in Pn.mat, and pe is not being found in Pe.mat and so on.

Possibly the variables are named Pn and Pe in the .mat files.

20 个评论
显示 18更早的评论隐藏 18更早的评论

DJ V 2024-10-17

移动：Torsten 2024-10-17

Doesn't seem to work. All I get back from the software is:

>> EqnsOfMotionback

timeseries with properties:

Events: []

Name: ''

UserData: []

Data: [101×1 double]

DataInfo: [1×1 tsdata.datametadata]

Time: [101×1 double]

TimeInfo: [1×1 tsdata.timemetadata]

Quality: []

QualityInfo: [1×1 tsdata.qualmetadata]

IsTimeFirst: 1

TreatNaNasMissing: 1

Length: 101

timeseries

Common Properties:

Name: ''

Time: [101x1 double]

TimeInfo: [1x1 tsdata.timemetadata]

Data: [101x1 double]

DataInfo: [1x1 tsdata.datametadata]

More properties, Methods

pe =

struct with fields:

pe: [1×1 timeseries]

pd =

struct with fields:

pd: [1×1 timeseries]

timeseries

Common Properties:

Name: ''

Time: [101x1 double]

TimeInfo: [1x1 tsdata.timemetadata]

Data: [101x1 double]

DataInfo: [1x1 tsdata.datametadata]

More properties, Methods

timeseries

Common Properties:

Name: ''

Time: [101x1 double]

TimeInfo: [1x1 tsdata.timemetadata]

Data: [101x1 double]

DataInfo: [1x1 tsdata.datametadata]

More properties, Methods

timeseries

Common Properties:

Name: ''

Time: [101x1 double]

TimeInfo: [1x1 tsdata.timemetadata]

Data: [101x1 double]

DataInfo: [1x1 tsdata.datametadata]

More properties, Methods

Undefined function 'cos' for input arguments of type 'timeseries'.

Error in EqnsOfMotionback>rotate (line 213)

0, cos(phi), -sin(phi);

Error in EqnsOfMotionback>drawPlaneBody (line 143)

NED = rotate(NED, phi, theta, psi);

Error in EqnsOfMotionback (line 113)

handle = drawPlaneBody(pn(k),pe(k),pd(k),phi(k),theta(k),psi(k),handle);

>>

Walter Roberson 2024-10-17

在 MATLAB Online 中打开

Those messages appear to be correct. The data stored in the .mat files is timeseries data.

I notice that some of your variables are turning out as struct . You should be using

pn = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pn.mat","ans").ans;
pe = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pe.mat","ans").ans;
pd = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pd.mat","ans").ans;
phi = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\phi.mat","ans").ans;
psi = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\psi.mat","ans").ans;
theta = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\theta.mat","ans").ans;

That will load each of the data as timeseries objects.

As timeseries objects, there is a Time field and a Data field. The Time fields are not generally guaranteed to be uniform intervals; however, you did configure fixed-timestep ode4 solver, so the Time fields will be uniform intervals in your case.

In all of the files I examined, the Data field is uniformly 0.

DJ V 2024-10-18

移动：Walter Roberson 2024-10-18

Okay, I'm having some trouble with the following code. It says:

Error in EqnsOfMotionback (line 95)

Pd = load("C:\Users\1537268928E\OneDrive - United States Air

Force\Desktop\Pd.mat", "ans").ans;

>> EqnsOfMotionback

Index in position 2 exceeds array bounds (must not exceed 1).

Error in EqnsOfMotionback (line 99)

pn=Pn.Data(1,200);

The code that this generally applied to is:

handle=[];

Pn = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pn.mat", "ans").ans;

Pe = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pe.mat", "ans").ans;

Pd = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\Pd.mat", "ans").ans;

Phi = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\phi.mat","ans").ans;

Psi = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\psi.mat","ans").ans;

Theta = load("C:\Users\1537268928E\OneDrive - United States Air Force\Desktop\theta.mat","ans").ans;

pn=Pn.Data(1,200);

pe=Pe.Data(1,200);

pd=Pd.Data(1,200);

phi=Phi.Data(1,200);

psi=Psi.Data(1,200);

theta=Theta.Data(1,200);

How can I reference individual elements of pn (from 1 to 200) if I can only enter 1 in the parenthesis?

Sorry, I'm new to this. It been a decade since I last used Matlab.

Thanks a lot.

Del Ventruella

Walter Roberson 2024-10-21

移动：Voss 2024-10-21

There is an implicit "1" to start with. The 1 is multiplied by the inputs that are marked as multiplication, and is divided by inputs that are marked as division. For example you could have two divisions A and B, and that would be (1/A) * (1/B)

DJ V 2024-10-22

移动：Voss 2024-10-22

Now, more fun. I'm trying to control the direction of motion of the aircraft, but it seem that when I do this, I move it off the screen instantly. The errors it is outputting are as follows:

Error using matlab.graphics.chart.primitive.Line/set

Invalid or deleted object.

Error in EqnsOfMotionback>drawPlaneBody (line 166)

set(handle, 'XData', XYZ(1,:), 'YData',XYZ(2,:), 'ZData',XYZ(3,:));

Error in EqnsOfMotionback (line 117)

handle =

drawPlaneBody(pn(k),pe(k),pd(k),phi(k),theta(k),psi(k),handle);

请先登录，再进行评论。

I need help to figure out why these variables aren't being found.

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

采纳的回答

20 个评论
显示 18更早的评论隐藏 18更早的评论

更多回答（0 个）

另请参阅

类别

标签

产品

版本

Community Treasure Hunt

I need help to figure out why these variables aren't being found.

0 个评论 显示 -2更早的评论隐藏 -2更早的评论

采纳的回答

20 个评论 显示 18更早的评论隐藏 18更早的评论

更多回答（0 个）

另请参阅

类别

标签

产品

版本

Community Treasure Hunt

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

20 个评论
显示 18更早的评论隐藏 18更早的评论