Tag Archives: matlab
Bug in readtable()? – if the first values in a CSV’s column are missing, the whole column is misinterpreted
I am reading a big CSV file (500K lines) with readtable. In the CSV, some columns have the first 250+ lines empty (e.g. ",,,," in the CSV), while the non-missing values below (pretty rare) are either text strings or dates (in the DD-MM-YYYY format). Readtable() somehow interprets these columns as numeric, and so converts all the strings and dates into NaNs – thus, I end up with 100% NaN-filled columns instead of rarely-populated data (among empty strings and NaTs).
Furthermore, if I move the "with-data" lines up – even a few dozens positions up – readtable() starts to read everything normally!
So, it looks like readtable() checks only ~250 first values to determine the type of the column, which, in my opinion, is a bug! (Although I understand that it was likely made to improve speed.)
Is there a way to fix it systematically? I have lots of such CSVs with thousands of columns in them – so, a manual check and manual fix is not an option…
UPD: a test-file (truncated to 510 lines) is attached – the behaviour is still the same. The problem columns are the 2nd and the 3rd (p190, p191). The first non-empty value is on data-line 270.I am reading a big CSV file (500K lines) with readtable. In the CSV, some columns have the first 250+ lines empty (e.g. ",,,," in the CSV), while the non-missing values below (pretty rare) are either text strings or dates (in the DD-MM-YYYY format). Readtable() somehow interprets these columns as numeric, and so converts all the strings and dates into NaNs – thus, I end up with 100% NaN-filled columns instead of rarely-populated data (among empty strings and NaTs).
Furthermore, if I move the "with-data" lines up – even a few dozens positions up – readtable() starts to read everything normally!
So, it looks like readtable() checks only ~250 first values to determine the type of the column, which, in my opinion, is a bug! (Although I understand that it was likely made to improve speed.)
Is there a way to fix it systematically? I have lots of such CSVs with thousands of columns in them – so, a manual check and manual fix is not an option…
UPD: a test-file (truncated to 510 lines) is attached – the behaviour is still the same. The problem columns are the 2nd and the 3rd (p190, p191). The first non-empty value is on data-line 270. I am reading a big CSV file (500K lines) with readtable. In the CSV, some columns have the first 250+ lines empty (e.g. ",,,," in the CSV), while the non-missing values below (pretty rare) are either text strings or dates (in the DD-MM-YYYY format). Readtable() somehow interprets these columns as numeric, and so converts all the strings and dates into NaNs – thus, I end up with 100% NaN-filled columns instead of rarely-populated data (among empty strings and NaTs).
Furthermore, if I move the "with-data" lines up – even a few dozens positions up – readtable() starts to read everything normally!
So, it looks like readtable() checks only ~250 first values to determine the type of the column, which, in my opinion, is a bug! (Although I understand that it was likely made to improve speed.)
Is there a way to fix it systematically? I have lots of such CSVs with thousands of columns in them – so, a manual check and manual fix is not an option…
UPD: a test-file (truncated to 510 lines) is attached – the behaviour is still the same. The problem columns are the 2nd and the 3rd (p190, p191). The first non-empty value is on data-line 270. readtable, missing values, csv MATLAB Answers — New Questions
How to add labels to lines on a plot in MATLAB?
When there are a lot of lines on a plot, it can be difficult to use a legend to distinguish individual lines. How can I label individual lines on a plot in MATLAB?When there are a lot of lines on a plot, it can be difficult to use a legend to distinguish individual lines. How can I label individual lines on a plot in MATLAB? When there are a lot of lines on a plot, it can be difficult to use a legend to distinguish individual lines. How can I label individual lines on a plot in MATLAB? legend, line, label, text, annotation MATLAB Answers — New Questions
Change configurations of the WLAN HDL examples of transmitter and receiver
Dear all,
I am recently trying to use the WLAN examples of the wireless HDL toolbox:
https://jp.mathworks.com/help/wireless-hdl/ug/wlanhdltransmitter.html
https://jp.mathworks.com/help/wireless-hdl/ug/wlanhdlreceiver.html
In these two examples of transmitter and receiver, it seems to support 802.11a/n/ac.
For instance, I would like to use 802.11n, then these should be selected:
HT: switched by "frameFormat"?
ODFM only: How to select?
MCS: which one should be select?
For 20 MHz channel bandwidth, which clock rare should be used in FPGA to drive the HDL codes?
ADC bit width: It seems to be 32 bit by default. How can I change to other bit width?
If I would like to use other than a/n/ac, how can I do?
For such kinds of the configurations or so, I would appreciate if anyone can instruct me how to change them before generating HDL.
Thank you in advance.Dear all,
I am recently trying to use the WLAN examples of the wireless HDL toolbox:
https://jp.mathworks.com/help/wireless-hdl/ug/wlanhdltransmitter.html
https://jp.mathworks.com/help/wireless-hdl/ug/wlanhdlreceiver.html
In these two examples of transmitter and receiver, it seems to support 802.11a/n/ac.
For instance, I would like to use 802.11n, then these should be selected:
HT: switched by "frameFormat"?
ODFM only: How to select?
MCS: which one should be select?
For 20 MHz channel bandwidth, which clock rare should be used in FPGA to drive the HDL codes?
ADC bit width: It seems to be 32 bit by default. How can I change to other bit width?
If I would like to use other than a/n/ac, how can I do?
For such kinds of the configurations or so, I would appreciate if anyone can instruct me how to change them before generating HDL.
Thank you in advance. Dear all,
I am recently trying to use the WLAN examples of the wireless HDL toolbox:
https://jp.mathworks.com/help/wireless-hdl/ug/wlanhdltransmitter.html
https://jp.mathworks.com/help/wireless-hdl/ug/wlanhdlreceiver.html
In these two examples of transmitter and receiver, it seems to support 802.11a/n/ac.
For instance, I would like to use 802.11n, then these should be selected:
HT: switched by "frameFormat"?
ODFM only: How to select?
MCS: which one should be select?
For 20 MHz channel bandwidth, which clock rare should be used in FPGA to drive the HDL codes?
ADC bit width: It seems to be 32 bit by default. How can I change to other bit width?
If I would like to use other than a/n/ac, how can I do?
For such kinds of the configurations or so, I would appreciate if anyone can instruct me how to change them before generating HDL.
Thank you in advance. wlan, wireless, hdl, simulink, matlab MATLAB Answers — New Questions
How to align multiline label and legend?
Hello
Using sprintf it is possible to create multiline labels in a legend. However, as shown in the example below, it would be better if the legend symbol (the colored line) would always be aligned with the first line of the multiline label, so aligned on top instead of being centered. The current output looks a bit confusing. Is it possible to control the position of the legend symbol w.r.t. the label?
Thanks in advance.
x=1:5;
y1=x;
y2=x.^2;
y3=x.^3;
plot(x,y1)
hold on
plot(x,y2)
plot(x,y3)
legend({‘first graph $y=x$’, sprintf(‘%sn%s’, ‘second graph’, ‘$y=x^2$’), sprintf(‘%sn%s’, ‘third graph’, ‘$y=x^3$’)}, ‘Interpreter’, ‘latex’)Hello
Using sprintf it is possible to create multiline labels in a legend. However, as shown in the example below, it would be better if the legend symbol (the colored line) would always be aligned with the first line of the multiline label, so aligned on top instead of being centered. The current output looks a bit confusing. Is it possible to control the position of the legend symbol w.r.t. the label?
Thanks in advance.
x=1:5;
y1=x;
y2=x.^2;
y3=x.^3;
plot(x,y1)
hold on
plot(x,y2)
plot(x,y3)
legend({‘first graph $y=x$’, sprintf(‘%sn%s’, ‘second graph’, ‘$y=x^2$’), sprintf(‘%sn%s’, ‘third graph’, ‘$y=x^3$’)}, ‘Interpreter’, ‘latex’) Hello
Using sprintf it is possible to create multiline labels in a legend. However, as shown in the example below, it would be better if the legend symbol (the colored line) would always be aligned with the first line of the multiline label, so aligned on top instead of being centered. The current output looks a bit confusing. Is it possible to control the position of the legend symbol w.r.t. the label?
Thanks in advance.
x=1:5;
y1=x;
y2=x.^2;
y3=x.^3;
plot(x,y1)
hold on
plot(x,y2)
plot(x,y3)
legend({‘first graph $y=x$’, sprintf(‘%sn%s’, ‘second graph’, ‘$y=x^2$’), sprintf(‘%sn%s’, ‘third graph’, ‘$y=x^3$’)}, ‘Interpreter’, ‘latex’) legend, multiline, align MATLAB Answers — New Questions
Why don’t gain and phase margins appear on my Bode plot?
I have discrete-time frequency response data in the form of a "frd" object. When I try to show the gain and phase margins associated with this data using the "bodeplot" function, these gain and phase margins do not appear on the plot. What am I missing?I have discrete-time frequency response data in the form of a "frd" object. When I try to show the gain and phase margins associated with this data using the "bodeplot" function, these gain and phase margins do not appear on the plot. What am I missing? I have discrete-time frequency response data in the form of a "frd" object. When I try to show the gain and phase margins associated with this data using the "bodeplot" function, these gain and phase margins do not appear on the plot. What am I missing? bodeplot, margin MATLAB Answers — New Questions
error “Error in untitled (line 9)”
I’m trying to run the following code, byt I have the error "Error in untitled (line 9) [t,x]=ode45(‘prob’,tspan,x0);" .
Why is that happening? Can anyone help me, please? Thank you!
%Numerical Solutions
%Problem #57
clc
clear
close all
%Numerical Solution
x0=[0;0];
tspan=[0 15];
[t,x]=ode45(‘prob’,tspan,x0);
figure(1)
plot(t,x(:,1));
title(‘Problem #57’);
xlabel(‘Time, sec.’);
ylabel(‘Displacement, m’);
hold on
%Analytical Solution
m=100;
c=20;
k=1000;
F=30;
w=sqrt(k/m);
d=c/(2*w*m);
wd=w*sqrt(1-d^2);
to=1;
phi=atan(d/sqrt(1-d^2));
%for t<to
t=linspace(0,1,3);
x=0.*t;
plot(t,x,’*’);
%for t>=to
t=linspace(1,15);
x=F/k-F/(k*sqrt(1-d^2)).*exp(-d.*w.*(t-to)).*cos(wd.*(t-to)-phi);
plot(t,x,’*’);
legend(‘Numerical’, ‘Analytical’)
%M-file for Prob #50
function dx=prob(t,x)
[rows, cols]=size(x);dx=zeros(rows, cols);
m=100;
c=20;
k=1000;
F=30;
if t<1
dx=0;
else
dx(1)=x(2);
dx(2)=-c/m*x(2) – k/m*x(1) + F/m;
end
endI’m trying to run the following code, byt I have the error "Error in untitled (line 9) [t,x]=ode45(‘prob’,tspan,x0);" .
Why is that happening? Can anyone help me, please? Thank you!
%Numerical Solutions
%Problem #57
clc
clear
close all
%Numerical Solution
x0=[0;0];
tspan=[0 15];
[t,x]=ode45(‘prob’,tspan,x0);
figure(1)
plot(t,x(:,1));
title(‘Problem #57’);
xlabel(‘Time, sec.’);
ylabel(‘Displacement, m’);
hold on
%Analytical Solution
m=100;
c=20;
k=1000;
F=30;
w=sqrt(k/m);
d=c/(2*w*m);
wd=w*sqrt(1-d^2);
to=1;
phi=atan(d/sqrt(1-d^2));
%for t<to
t=linspace(0,1,3);
x=0.*t;
plot(t,x,’*’);
%for t>=to
t=linspace(1,15);
x=F/k-F/(k*sqrt(1-d^2)).*exp(-d.*w.*(t-to)).*cos(wd.*(t-to)-phi);
plot(t,x,’*’);
legend(‘Numerical’, ‘Analytical’)
%M-file for Prob #50
function dx=prob(t,x)
[rows, cols]=size(x);dx=zeros(rows, cols);
m=100;
c=20;
k=1000;
F=30;
if t<1
dx=0;
else
dx(1)=x(2);
dx(2)=-c/m*x(2) – k/m*x(1) + F/m;
end
end I’m trying to run the following code, byt I have the error "Error in untitled (line 9) [t,x]=ode45(‘prob’,tspan,x0);" .
Why is that happening? Can anyone help me, please? Thank you!
%Numerical Solutions
%Problem #57
clc
clear
close all
%Numerical Solution
x0=[0;0];
tspan=[0 15];
[t,x]=ode45(‘prob’,tspan,x0);
figure(1)
plot(t,x(:,1));
title(‘Problem #57’);
xlabel(‘Time, sec.’);
ylabel(‘Displacement, m’);
hold on
%Analytical Solution
m=100;
c=20;
k=1000;
F=30;
w=sqrt(k/m);
d=c/(2*w*m);
wd=w*sqrt(1-d^2);
to=1;
phi=atan(d/sqrt(1-d^2));
%for t<to
t=linspace(0,1,3);
x=0.*t;
plot(t,x,’*’);
%for t>=to
t=linspace(1,15);
x=F/k-F/(k*sqrt(1-d^2)).*exp(-d.*w.*(t-to)).*cos(wd.*(t-to)-phi);
plot(t,x,’*’);
legend(‘Numerical’, ‘Analytical’)
%M-file for Prob #50
function dx=prob(t,x)
[rows, cols]=size(x);dx=zeros(rows, cols);
m=100;
c=20;
k=1000;
F=30;
if t<1
dx=0;
else
dx(1)=x(2);
dx(2)=-c/m*x(2) – k/m*x(1) + F/m;
end
end error untitled MATLAB Answers — New Questions
Reading multiple sheets from an excel file
I have an excel spreadsheet and the data is seperated into a different sheet for each year but I want to have all of the years worth of data in one table so I was wondering what the best way to approach this is? Right now my code only gets the data from 2007 and thats it.
opt=detectImportOptions(‘BC1 2007-2020.xlsx’);
opt.VariableTypes(3)={‘double’};
BC1=readtable(‘BC1 2007-2020.xlsx’,opt);
BC1.Date=datetime(BC1{:,1},’InputFormat’,’dd/MM/yy HH:mm:ss’);
BC1=table2timetable(BC1);
plot(BC1.Date,BC1.WaterLevel_Meters);I have an excel spreadsheet and the data is seperated into a different sheet for each year but I want to have all of the years worth of data in one table so I was wondering what the best way to approach this is? Right now my code only gets the data from 2007 and thats it.
opt=detectImportOptions(‘BC1 2007-2020.xlsx’);
opt.VariableTypes(3)={‘double’};
BC1=readtable(‘BC1 2007-2020.xlsx’,opt);
BC1.Date=datetime(BC1{:,1},’InputFormat’,’dd/MM/yy HH:mm:ss’);
BC1=table2timetable(BC1);
plot(BC1.Date,BC1.WaterLevel_Meters); I have an excel spreadsheet and the data is seperated into a different sheet for each year but I want to have all of the years worth of data in one table so I was wondering what the best way to approach this is? Right now my code only gets the data from 2007 and thats it.
opt=detectImportOptions(‘BC1 2007-2020.xlsx’);
opt.VariableTypes(3)={‘double’};
BC1=readtable(‘BC1 2007-2020.xlsx’,opt);
BC1.Date=datetime(BC1{:,1},’InputFormat’,’dd/MM/yy HH:mm:ss’);
BC1=table2timetable(BC1);
plot(BC1.Date,BC1.WaterLevel_Meters); excel MATLAB Answers — New Questions
Pass bus signals to a function as an array (Stateflow)
Hello!
I’m working within stateflow and defining a transition check:
[checkInRange(User_CMDs.r,0,1)==1]
Check In range is a simple function as follows and returns true if all inputs are true (In Range):
function result = checkInRange(input,request,tolerance)
result = abs(request – input) <= tolerance;
result = all(result(:));
end
Ive been able to pass arrays as input to the function, however i am trying to define a transition and for a state within simulink. The User_CMD.r is a bus with 4 singals called X1, X2, X3 and X4. I need all of these to be in range for state transition. Is there a way of doing this without doing it as below?
[checkInRange([User_CMDs.r.X1,User_CMDs.r.X1,User_CMDs.r.X1,User_CMDs.r.X1], 0,1)==1]Hello!
I’m working within stateflow and defining a transition check:
[checkInRange(User_CMDs.r,0,1)==1]
Check In range is a simple function as follows and returns true if all inputs are true (In Range):
function result = checkInRange(input,request,tolerance)
result = abs(request – input) <= tolerance;
result = all(result(:));
end
Ive been able to pass arrays as input to the function, however i am trying to define a transition and for a state within simulink. The User_CMD.r is a bus with 4 singals called X1, X2, X3 and X4. I need all of these to be in range for state transition. Is there a way of doing this without doing it as below?
[checkInRange([User_CMDs.r.X1,User_CMDs.r.X1,User_CMDs.r.X1,User_CMDs.r.X1], 0,1)==1] Hello!
I’m working within stateflow and defining a transition check:
[checkInRange(User_CMDs.r,0,1)==1]
Check In range is a simple function as follows and returns true if all inputs are true (In Range):
function result = checkInRange(input,request,tolerance)
result = abs(request – input) <= tolerance;
result = all(result(:));
end
Ive been able to pass arrays as input to the function, however i am trying to define a transition and for a state within simulink. The User_CMD.r is a bus with 4 singals called X1, X2, X3 and X4. I need all of these to be in range for state transition. Is there a way of doing this without doing it as below?
[checkInRange([User_CMDs.r.X1,User_CMDs.r.X1,User_CMDs.r.X1,User_CMDs.r.X1], 0,1)==1] stateflow, signal bus, bus MATLAB Answers — New Questions
Interactive point selection 3D points
Hello,
I need your help.
In the image bellow (hopefully it did work this time) there is a three-dimensional tooth on the left (with its three-dimensional coordinates, of course) and on the left the same tooth but in a two-dimensional parameterised disc. The order of the points on the 2D and 3D vectors are the same, that is, the points are corresponding.
I woud like to select a point on the 3D tooth and get the same point marked on the right 2D tooth. I can do this the other way around, that is, selecting a point on the disc and then getting the correspondent on the 3D figure.
My method for doing this on the 2D was with the function getpts, which gives me the coordinates of the mouse where I click. I then take the nearest neighbour of that point (or points) and plot the corresponding points on the 3D figure with its correct indexes.
So my question is, is there a similar function to getpts() for a 3D figure?
Thank you :)Hello,
I need your help.
In the image bellow (hopefully it did work this time) there is a three-dimensional tooth on the left (with its three-dimensional coordinates, of course) and on the left the same tooth but in a two-dimensional parameterised disc. The order of the points on the 2D and 3D vectors are the same, that is, the points are corresponding.
I woud like to select a point on the 3D tooth and get the same point marked on the right 2D tooth. I can do this the other way around, that is, selecting a point on the disc and then getting the correspondent on the 3D figure.
My method for doing this on the 2D was with the function getpts, which gives me the coordinates of the mouse where I click. I then take the nearest neighbour of that point (or points) and plot the corresponding points on the 3D figure with its correct indexes.
So my question is, is there a similar function to getpts() for a 3D figure?
Thank you 🙂 Hello,
I need your help.
In the image bellow (hopefully it did work this time) there is a three-dimensional tooth on the left (with its three-dimensional coordinates, of course) and on the left the same tooth but in a two-dimensional parameterised disc. The order of the points on the 2D and 3D vectors are the same, that is, the points are corresponding.
I woud like to select a point on the 3D tooth and get the same point marked on the right 2D tooth. I can do this the other way around, that is, selecting a point on the disc and then getting the correspondent on the 3D figure.
My method for doing this on the 2D was with the function getpts, which gives me the coordinates of the mouse where I click. I then take the nearest neighbour of that point (or points) and plot the corresponding points on the 3D figure with its correct indexes.
So my question is, is there a similar function to getpts() for a 3D figure?
Thank you 🙂 3d getpts MATLAB Answers — New Questions
how to make transformation in mp4 vedio
i have two vedio of mp4.i want to apply some tranformation on it and run the tranform vedio.i have wriiten the code but contently facing the error.i even tried "NumberOfFrames" but it is unrecongnized in my matlab
code is here
% read videos
vid1 = VideoReader(‘video1.mp4’);
vid2 = VideoReader(‘vedio2.mp4’);
% read first frame from each video
frame1 = readFrame(vid1);
frame2 = readFrame(vid2);
% create a figure
fig = figure;
while hasFrame(vid1) && hasFrame(vid2)
% read frames from each video
frame1 = readFrame(vid1);
frame2 = readFrame(vid2);
% perform geometric transformations
frame1_scaled = imresize(frame1, 0.5);
frame1_sheared = imresize(frame1, [size(frame1,1) size(frame1,2)*0.8]);
frame1_rotated = imrotate(frame1, 30, ‘crop’);
frame2_scaled = imresize(frame2, 0.5);
frame2_sheared = imresize(frame2, [size(frame2,1) size(frame2,2)*0.8]);
frame2_rotated = imrotate(frame2, -30, ‘crop’);
% concatenate frames
combined_frame = cat(2, cat(1, frame1, frame1_scaled, frame1_sheared, frame1_rotated), …
cat(1, frame2, frame2_scaled, frame2_sheared, frame2_rotated));
% display frames
imshow(combined_frame, ‘Parent’, fig);
drawnow;
end
error that i facing is
Error using cat
Dimensions
of
arrays
being
concatenated
are
not
consistent.
Error in untitled (line 27)
combined_frame = cat(2, cat(1, frame1, frame1_scaled, frame1_sheared, frame1_rotated), …i have two vedio of mp4.i want to apply some tranformation on it and run the tranform vedio.i have wriiten the code but contently facing the error.i even tried "NumberOfFrames" but it is unrecongnized in my matlab
code is here
% read videos
vid1 = VideoReader(‘video1.mp4’);
vid2 = VideoReader(‘vedio2.mp4’);
% read first frame from each video
frame1 = readFrame(vid1);
frame2 = readFrame(vid2);
% create a figure
fig = figure;
while hasFrame(vid1) && hasFrame(vid2)
% read frames from each video
frame1 = readFrame(vid1);
frame2 = readFrame(vid2);
% perform geometric transformations
frame1_scaled = imresize(frame1, 0.5);
frame1_sheared = imresize(frame1, [size(frame1,1) size(frame1,2)*0.8]);
frame1_rotated = imrotate(frame1, 30, ‘crop’);
frame2_scaled = imresize(frame2, 0.5);
frame2_sheared = imresize(frame2, [size(frame2,1) size(frame2,2)*0.8]);
frame2_rotated = imrotate(frame2, -30, ‘crop’);
% concatenate frames
combined_frame = cat(2, cat(1, frame1, frame1_scaled, frame1_sheared, frame1_rotated), …
cat(1, frame2, frame2_scaled, frame2_sheared, frame2_rotated));
% display frames
imshow(combined_frame, ‘Parent’, fig);
drawnow;
end
error that i facing is
Error using cat
Dimensions
of
arrays
being
concatenated
are
not
consistent.
Error in untitled (line 27)
combined_frame = cat(2, cat(1, frame1, frame1_scaled, frame1_sheared, frame1_rotated), … i have two vedio of mp4.i want to apply some tranformation on it and run the tranform vedio.i have wriiten the code but contently facing the error.i even tried "NumberOfFrames" but it is unrecongnized in my matlab
code is here
% read videos
vid1 = VideoReader(‘video1.mp4’);
vid2 = VideoReader(‘vedio2.mp4’);
% read first frame from each video
frame1 = readFrame(vid1);
frame2 = readFrame(vid2);
% create a figure
fig = figure;
while hasFrame(vid1) && hasFrame(vid2)
% read frames from each video
frame1 = readFrame(vid1);
frame2 = readFrame(vid2);
% perform geometric transformations
frame1_scaled = imresize(frame1, 0.5);
frame1_sheared = imresize(frame1, [size(frame1,1) size(frame1,2)*0.8]);
frame1_rotated = imrotate(frame1, 30, ‘crop’);
frame2_scaled = imresize(frame2, 0.5);
frame2_sheared = imresize(frame2, [size(frame2,1) size(frame2,2)*0.8]);
frame2_rotated = imrotate(frame2, -30, ‘crop’);
% concatenate frames
combined_frame = cat(2, cat(1, frame1, frame1_scaled, frame1_sheared, frame1_rotated), …
cat(1, frame2, frame2_scaled, frame2_sheared, frame2_rotated));
% display frames
imshow(combined_frame, ‘Parent’, fig);
drawnow;
end
error that i facing is
Error using cat
Dimensions
of
arrays
being
concatenated
are
not
consistent.
Error in untitled (line 27)
combined_frame = cat(2, cat(1, frame1, frame1_scaled, frame1_sheared, frame1_rotated), … video processing, transformation MATLAB Answers — New Questions
Correct way to calculate the dominant frequency of time series signal?
My dataset consists of two parameters: time (in micro second) and amplitude (Attached):
I am particularly interested in analyzing the fluctuation of the dominant frequency across the entire dataset. Additionally, I want to examine how the frequency content changes as a function of time. For instance, in time intervals such as 0–200 ms, 100–300 ms, 300–500 ms, and so on.
I attempted multiple approaches, but the results are not very consistent. I would be interested in getting a second opinion.
Thanks in Advance!My dataset consists of two parameters: time (in micro second) and amplitude (Attached):
I am particularly interested in analyzing the fluctuation of the dominant frequency across the entire dataset. Additionally, I want to examine how the frequency content changes as a function of time. For instance, in time intervals such as 0–200 ms, 100–300 ms, 300–500 ms, and so on.
I attempted multiple approaches, but the results are not very consistent. I would be interested in getting a second opinion.
Thanks in Advance! My dataset consists of two parameters: time (in micro second) and amplitude (Attached):
I am particularly interested in analyzing the fluctuation of the dominant frequency across the entire dataset. Additionally, I want to examine how the frequency content changes as a function of time. For instance, in time intervals such as 0–200 ms, 100–300 ms, 300–500 ms, and so on.
I attempted multiple approaches, but the results are not very consistent. I would be interested in getting a second opinion.
Thanks in Advance! time series, fft MATLAB Answers — New Questions
prev value in a stateflow chart
Stateflow documentation:
…To detect changes, the chart automatically double-buffers these values in local variables, as follows:
var_name_prev Value of data at the beginning of the last time step
var_name_start Value of data at the beginning of the current time step
Question: do I have read access to the buffered variables? I want to use them for calculations inside the stateflow chart.Stateflow documentation:
…To detect changes, the chart automatically double-buffers these values in local variables, as follows:
var_name_prev Value of data at the beginning of the last time step
var_name_start Value of data at the beginning of the current time step
Question: do I have read access to the buffered variables? I want to use them for calculations inside the stateflow chart. Stateflow documentation:
…To detect changes, the chart automatically double-buffers these values in local variables, as follows:
var_name_prev Value of data at the beginning of the last time step
var_name_start Value of data at the beginning of the current time step
Question: do I have read access to the buffered variables? I want to use them for calculations inside the stateflow chart. stateflow, double-buffer MATLAB Answers — New Questions
How to arrange elements in one array to match the position of elements in a second array?
If I have two arrays A and B as displayed below, how can I rearrange B such that a new boolean array Ba which corresponds to the values of array B can be resorted according to the values of array A instead?
For example, if I have:
A =
1 5 3 2 4 4 2 2 3 5
2 1 1 2 0 1 1 1 0 0
30 22 23 25 -1 30 18 25 -1 -1
B =
1 2 2 2 3 3 4 4 5 5
2 1 1 2 0 1 0 1 0 1
30 18 25 25 -1 23 -1 30 -1 22
Ba =
0 0 1 0 1 0 0 0 0 0
Note that array B is simply the sorted version of array A according to the first row in an ascended order. It is resorted twice according to the second row in an ascended order for the values in row 1 that equal one another (e.g., if there are multiples elements equal to 3 in row 1, then the array will sort by the second row instead, so if the second row has values 3 3 3 3 3; 2 6 3 9 1, it will then be sorted to 3 3 3 3 3; 1 2 3 6 9)
I only mentioned this in case reverse sorting might work easier than entirely rearranging the position of the array.
I want to rearrange array B and Ba such that it corresponds to the positioning of array A.
So the new arrays would look like this:
A =
1 5 3 2 4 4 2 2 3 5
2 1 1 2 0 1 1 1 0 0
30 22 23 25 -1 30 18 25 -1 -1
Aa =
0 0 0 0 0 0 0 1 1 0
The new array would essentially match A, and the array Aa is the same array Ba but now rearranged so that it follows the arrangement of A rather than B.
I am not entirely sure how to write the MATLAB code to accomplish this. All help is appreciated!If I have two arrays A and B as displayed below, how can I rearrange B such that a new boolean array Ba which corresponds to the values of array B can be resorted according to the values of array A instead?
For example, if I have:
A =
1 5 3 2 4 4 2 2 3 5
2 1 1 2 0 1 1 1 0 0
30 22 23 25 -1 30 18 25 -1 -1
B =
1 2 2 2 3 3 4 4 5 5
2 1 1 2 0 1 0 1 0 1
30 18 25 25 -1 23 -1 30 -1 22
Ba =
0 0 1 0 1 0 0 0 0 0
Note that array B is simply the sorted version of array A according to the first row in an ascended order. It is resorted twice according to the second row in an ascended order for the values in row 1 that equal one another (e.g., if there are multiples elements equal to 3 in row 1, then the array will sort by the second row instead, so if the second row has values 3 3 3 3 3; 2 6 3 9 1, it will then be sorted to 3 3 3 3 3; 1 2 3 6 9)
I only mentioned this in case reverse sorting might work easier than entirely rearranging the position of the array.
I want to rearrange array B and Ba such that it corresponds to the positioning of array A.
So the new arrays would look like this:
A =
1 5 3 2 4 4 2 2 3 5
2 1 1 2 0 1 1 1 0 0
30 22 23 25 -1 30 18 25 -1 -1
Aa =
0 0 0 0 0 0 0 1 1 0
The new array would essentially match A, and the array Aa is the same array Ba but now rearranged so that it follows the arrangement of A rather than B.
I am not entirely sure how to write the MATLAB code to accomplish this. All help is appreciated! If I have two arrays A and B as displayed below, how can I rearrange B such that a new boolean array Ba which corresponds to the values of array B can be resorted according to the values of array A instead?
For example, if I have:
A =
1 5 3 2 4 4 2 2 3 5
2 1 1 2 0 1 1 1 0 0
30 22 23 25 -1 30 18 25 -1 -1
B =
1 2 2 2 3 3 4 4 5 5
2 1 1 2 0 1 0 1 0 1
30 18 25 25 -1 23 -1 30 -1 22
Ba =
0 0 1 0 1 0 0 0 0 0
Note that array B is simply the sorted version of array A according to the first row in an ascended order. It is resorted twice according to the second row in an ascended order for the values in row 1 that equal one another (e.g., if there are multiples elements equal to 3 in row 1, then the array will sort by the second row instead, so if the second row has values 3 3 3 3 3; 2 6 3 9 1, it will then be sorted to 3 3 3 3 3; 1 2 3 6 9)
I only mentioned this in case reverse sorting might work easier than entirely rearranging the position of the array.
I want to rearrange array B and Ba such that it corresponds to the positioning of array A.
So the new arrays would look like this:
A =
1 5 3 2 4 4 2 2 3 5
2 1 1 2 0 1 1 1 0 0
30 22 23 25 -1 30 18 25 -1 -1
Aa =
0 0 0 0 0 0 0 1 1 0
The new array would essentially match A, and the array Aa is the same array Ba but now rearranged so that it follows the arrangement of A rather than B.
I am not entirely sure how to write the MATLAB code to accomplish this. All help is appreciated! array, sort MATLAB Answers — New Questions
STL to solid 3d matrix
Is there a way to import STL and save it as 3D matrix and stlil maintain its size? Patch is a good function to import stl, I need voxelisation of the mesh so I can slice the 2D data out of it.
This is a good work by Adam , but it does not maintain the size and ratio:
https://uk.mathworks.com/matlabcentral/fileexchange/27390-mesh-voxelisation
RegardsIs there a way to import STL and save it as 3D matrix and stlil maintain its size? Patch is a good function to import stl, I need voxelisation of the mesh so I can slice the 2D data out of it.
This is a good work by Adam , but it does not maintain the size and ratio:
https://uk.mathworks.com/matlabcentral/fileexchange/27390-mesh-voxelisation
Regards Is there a way to import STL and save it as 3D matrix and stlil maintain its size? Patch is a good function to import stl, I need voxelisation of the mesh so I can slice the 2D data out of it.
This is a good work by Adam , but it does not maintain the size and ratio:
https://uk.mathworks.com/matlabcentral/fileexchange/27390-mesh-voxelisation
Regards stl, patch, voxelisation MATLAB Answers — New Questions
How to get the values of x axis only visible at the bottom subplots?
Hi,
I have a series of subplots (5×4). Every subplot has the same x axis and the same limits. At the moment, I have the values of x axis visible in every subplot. I would like to have the values only visible at the bottom subplots, so that the figure would be simpler. I already edited the code so that the x label is only visible at the bottom subplots. But how do I do the same to the x axis values?
I tried turning of the ‘XTick’
set(gca,’XTick’,[]);
This worked, however, now the grid also turned off. How can I get the values to be only at the bottom subplots, and the grid on?
The same goes for y axis. I only want the values of the y axis to be visible at the left subplots.
Thank you in advance for any answers!Hi,
I have a series of subplots (5×4). Every subplot has the same x axis and the same limits. At the moment, I have the values of x axis visible in every subplot. I would like to have the values only visible at the bottom subplots, so that the figure would be simpler. I already edited the code so that the x label is only visible at the bottom subplots. But how do I do the same to the x axis values?
I tried turning of the ‘XTick’
set(gca,’XTick’,[]);
This worked, however, now the grid also turned off. How can I get the values to be only at the bottom subplots, and the grid on?
The same goes for y axis. I only want the values of the y axis to be visible at the left subplots.
Thank you in advance for any answers! Hi,
I have a series of subplots (5×4). Every subplot has the same x axis and the same limits. At the moment, I have the values of x axis visible in every subplot. I would like to have the values only visible at the bottom subplots, so that the figure would be simpler. I already edited the code so that the x label is only visible at the bottom subplots. But how do I do the same to the x axis values?
I tried turning of the ‘XTick’
set(gca,’XTick’,[]);
This worked, however, now the grid also turned off. How can I get the values to be only at the bottom subplots, and the grid on?
The same goes for y axis. I only want the values of the y axis to be visible at the left subplots.
Thank you in advance for any answers! subplot, axes, xlabel, xvalue MATLAB Answers — New Questions
Are dlnetworks supposed to be allowed to have output layers?
Are dlnetworks allowed to have output layers? In the following code, I manage to create one, so the answer would seem to be yes.
layers= [imageInputLayer([1,1,1]) , reluLayer(Name=’relu’) ] ;
dln = replaceLayer( dlnetwork(layers) ,’relu’, regressionLayer);
class(dln)
dln.Layers
However, when I try to create this more directly, an error is raised:
dln = dlnetwork( [imageInputLayer([1,1,1]) , regressionLayer] )
Have I found an unintended backdoor?Are dlnetworks allowed to have output layers? In the following code, I manage to create one, so the answer would seem to be yes.
layers= [imageInputLayer([1,1,1]) , reluLayer(Name=’relu’) ] ;
dln = replaceLayer( dlnetwork(layers) ,’relu’, regressionLayer);
class(dln)
dln.Layers
However, when I try to create this more directly, an error is raised:
dln = dlnetwork( [imageInputLayer([1,1,1]) , regressionLayer] )
Have I found an unintended backdoor? Are dlnetworks allowed to have output layers? In the following code, I manage to create one, so the answer would seem to be yes.
layers= [imageInputLayer([1,1,1]) , reluLayer(Name=’relu’) ] ;
dln = replaceLayer( dlnetwork(layers) ,’relu’, regressionLayer);
class(dln)
dln.Layers
However, when I try to create this more directly, an error is raised:
dln = dlnetwork( [imageInputLayer([1,1,1]) , regressionLayer] )
Have I found an unintended backdoor? dlnetwork, output layer MATLAB Answers — New Questions
Inserting Table from Matlab into Powerpoint slide
Does anyone know how to insert a table from MATLAB to a powerpoint slide?
For example:
header = cell{1,3};
header = {‘Header1’ ‘Header2’ ‘Header 3’};
data= [1, 2, 3;
1, 4, 9;];
How would one output this to powerpoint? I’ve seen the Matlab figures to powerpoint copying and pasting, but not sure how to insert a table.
Thanks for your help!Does anyone know how to insert a table from MATLAB to a powerpoint slide?
For example:
header = cell{1,3};
header = {‘Header1’ ‘Header2’ ‘Header 3’};
data= [1, 2, 3;
1, 4, 9;];
How would one output this to powerpoint? I’ve seen the Matlab figures to powerpoint copying and pasting, but not sure how to insert a table.
Thanks for your help! Does anyone know how to insert a table from MATLAB to a powerpoint slide?
For example:
header = cell{1,3};
header = {‘Header1’ ‘Header2’ ‘Header 3’};
data= [1, 2, 3;
1, 4, 9;];
How would one output this to powerpoint? I’ve seen the Matlab figures to powerpoint copying and pasting, but not sure how to insert a table.
Thanks for your help! powerpoint, table, inserting MATLAB Answers — New Questions
IK solver algorithm fminconsqp performance (2025a prerelease)
Hello everyone,
I’ve been testing 2025a prerelease matlab version’s new IK solver algorithm fminconsqp with default parameters, but BFGS with random restart enabled (while keeping other parameters default) still seems more powerful.
Am I missing something? I can’t quite figure out the advantage of this new solver.
Thanks in advance!Hello everyone,
I’ve been testing 2025a prerelease matlab version’s new IK solver algorithm fminconsqp with default parameters, but BFGS with random restart enabled (while keeping other parameters default) still seems more powerful.
Am I missing something? I can’t quite figure out the advantage of this new solver.
Thanks in advance! Hello everyone,
I’ve been testing 2025a prerelease matlab version’s new IK solver algorithm fminconsqp with default parameters, but BFGS with random restart enabled (while keeping other parameters default) still seems more powerful.
Am I missing something? I can’t quite figure out the advantage of this new solver.
Thanks in advance! matlab MATLAB Answers — New Questions
How to ensure that all values are not equal when using the ecef2enu function
I’m doing coordinate system transformation using the ecef2enu function. But for some reason, all three E, N, and U values are the same. I wonder why. How can I modify it to get the exact value?
Isn’t it normal for the 1, 2, 3 matrices to have different values? Is there something wrong with my code?
currTime = gnss.SensorModel.InitialTime;
setup(scene)
wgs84 = wgs84Ellipsoid(‘meter’);
while scene.IsRunning
[~,~,p,satPos,status] = gnss.read ();
allSatPos = gnssconstellation(currTime); % ecef
currTime = currTime + seconds(1/scene.UpdateRate);
[~,trueRecPos] = plat.read; % lla
trueRecPos_ecef = lla2ecef(trueRecPos); % uav ecef
[az,el] = lookangles(trueRecPos,satPos,gnss.SensorModel.MaskAngle);
nsat = length(satPos(:,1));
enu_sat = zeros(nsat,3);
for k = 1:1:nsat
enu_sat(k,:) = ecef2enu(satPos(k,1),satPos(k,2),satPos(k,3),trueRecPos(1),trueRecPos(2),trueRecPos(3),wgs84);
end
temp=1;
unit_sat = normalize(enu_sat,’norm’,1);
target_z = 500;
scale_factors = target_z ./ unit_sat(:,3);
unit_sat_scaled = unit_sat .* scale_factors;
endI’m doing coordinate system transformation using the ecef2enu function. But for some reason, all three E, N, and U values are the same. I wonder why. How can I modify it to get the exact value?
Isn’t it normal for the 1, 2, 3 matrices to have different values? Is there something wrong with my code?
currTime = gnss.SensorModel.InitialTime;
setup(scene)
wgs84 = wgs84Ellipsoid(‘meter’);
while scene.IsRunning
[~,~,p,satPos,status] = gnss.read ();
allSatPos = gnssconstellation(currTime); % ecef
currTime = currTime + seconds(1/scene.UpdateRate);
[~,trueRecPos] = plat.read; % lla
trueRecPos_ecef = lla2ecef(trueRecPos); % uav ecef
[az,el] = lookangles(trueRecPos,satPos,gnss.SensorModel.MaskAngle);
nsat = length(satPos(:,1));
enu_sat = zeros(nsat,3);
for k = 1:1:nsat
enu_sat(k,:) = ecef2enu(satPos(k,1),satPos(k,2),satPos(k,3),trueRecPos(1),trueRecPos(2),trueRecPos(3),wgs84);
end
temp=1;
unit_sat = normalize(enu_sat,’norm’,1);
target_z = 500;
scale_factors = target_z ./ unit_sat(:,3);
unit_sat_scaled = unit_sat .* scale_factors;
end I’m doing coordinate system transformation using the ecef2enu function. But for some reason, all three E, N, and U values are the same. I wonder why. How can I modify it to get the exact value?
Isn’t it normal for the 1, 2, 3 matrices to have different values? Is there something wrong with my code?
currTime = gnss.SensorModel.InitialTime;
setup(scene)
wgs84 = wgs84Ellipsoid(‘meter’);
while scene.IsRunning
[~,~,p,satPos,status] = gnss.read ();
allSatPos = gnssconstellation(currTime); % ecef
currTime = currTime + seconds(1/scene.UpdateRate);
[~,trueRecPos] = plat.read; % lla
trueRecPos_ecef = lla2ecef(trueRecPos); % uav ecef
[az,el] = lookangles(trueRecPos,satPos,gnss.SensorModel.MaskAngle);
nsat = length(satPos(:,1));
enu_sat = zeros(nsat,3);
for k = 1:1:nsat
enu_sat(k,:) = ecef2enu(satPos(k,1),satPos(k,2),satPos(k,3),trueRecPos(1),trueRecPos(2),trueRecPos(3),wgs84);
end
temp=1;
unit_sat = normalize(enu_sat,’norm’,1);
target_z = 500;
scale_factors = target_z ./ unit_sat(:,3);
unit_sat_scaled = unit_sat .* scale_factors;
end optimization, gnss, ecef2enu, enu, ecef MATLAB Answers — New Questions
Why is my Simulink Desktop Real-Time simulation very slow or halts in Windows when Hyper-V is enabled?
I am trying to use Simulink Desktop Real-Time (SLDRT) on my Windows machine, but when I launch the example model "sldrtex_vdp.slx", it runs very slow, halts, or may even cause a blue-screen.
The following warning message may be prompted out:
Warning: The "Real-Time Synchronization" block has timed out while
trying to synchronize to real-time kernel.
The following warning messages may be shown in Diagnostic Viewer:
Model sldrtex_vdp loaded
A disconnect message was sent to the target 10 seconds ago. Waiting for response.. [6 similar]
Never received disconnect response from target. Disconnecting…
Model sldrtex_vdp unloaded
Additionally, I may see the following error message during the kernel installation (since R2019b) or when trying to run a real-time simulation (since R2020b):
The Hyper-V hypervisor has been detected. The Simulink Desktop Real-Time kernel
cannot run in the presence of the hypervisor. Please disable the Hyper-V operating
system component before attempting to use Simulink Desktop Real-Time.I am trying to use Simulink Desktop Real-Time (SLDRT) on my Windows machine, but when I launch the example model "sldrtex_vdp.slx", it runs very slow, halts, or may even cause a blue-screen.
The following warning message may be prompted out:
Warning: The "Real-Time Synchronization" block has timed out while
trying to synchronize to real-time kernel.
The following warning messages may be shown in Diagnostic Viewer:
Model sldrtex_vdp loaded
A disconnect message was sent to the target 10 seconds ago. Waiting for response.. [6 similar]
Never received disconnect response from target. Disconnecting…
Model sldrtex_vdp unloaded
Additionally, I may see the following error message during the kernel installation (since R2019b) or when trying to run a real-time simulation (since R2020b):
The Hyper-V hypervisor has been detected. The Simulink Desktop Real-Time kernel
cannot run in the presence of the hypervisor. Please disable the Hyper-V operating
system component before attempting to use Simulink Desktop Real-Time. I am trying to use Simulink Desktop Real-Time (SLDRT) on my Windows machine, but when I launch the example model "sldrtex_vdp.slx", it runs very slow, halts, or may even cause a blue-screen.
The following warning message may be prompted out:
Warning: The "Real-Time Synchronization" block has timed out while
trying to synchronize to real-time kernel.
The following warning messages may be shown in Diagnostic Viewer:
Model sldrtex_vdp loaded
A disconnect message was sent to the target 10 seconds ago. Waiting for response.. [6 similar]
Never received disconnect response from target. Disconnecting…
Model sldrtex_vdp unloaded
Additionally, I may see the following error message during the kernel installation (since R2019b) or when trying to run a real-time simulation (since R2020b):
The Hyper-V hypervisor has been detected. The Simulink Desktop Real-Time kernel
cannot run in the presence of the hypervisor. Please disable the Hyper-V operating
system component before attempting to use Simulink Desktop Real-Time. slow, timeout, sldrt, bluescreen, bsod, hyper-v, hypervisor MATLAB Answers — New Questions
