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Contests
Hi, I have a table looking for a way to calculate the UserAcceleration of a mobile phone and as input I have array of yaw, pitch, roll (in degrees).
I've managed to calculate gravity(x, y, z) m/s^2 and rotation rate(x, y, z) in degree/s but not the angular acceleration, here are my calculations until now:
https://pastebin.com/raw/MEbhBnkE
Could someone help me to calculate user acceleration as well?
Thanks
General
Hi everyone,
for my thesis project I would need to get, every second of the simulation, real-time output data from a Simulink model, without using Simulink Real-Time, as it supports only Speedgoat Hardware. Is there a particular set of blocks for that purpose?
I have to provide that real-time data to hardware for an Hardware in the Loop Simulation so I will need to be able also to receive, as an input, data from the hardware to the Simulink model, again every second of the simulation, to close the loop of the simulation.
Thank you in advance for your support.
General
Sushil Kunwar
Sushil Kunwar
Posted on 8 Dec 2023 at 0:02

Curve line plot

Hi! I am using matlab inbuilt plot option( without typing code) to plot the data. This joins the data points using straight line by default. What will be the easiest way to plot if I want curve to join the points instead?
Ideas
Quick answer: Add set(hS,'Color',[0 0.4470 0.7410]) to code line 329
Explanation: Function corrplot uses functions plotmatrix and lsline. In lsline get(hh(k),'Color') is called in for cycle for each line and scatter object in axes. Inside the corrplot it is also called for all axes, which is slow. However, when you first set the color to any given value, internal optimization makes it much faster. I chose [0 0.4470 0.7410], because it is a default color for plotmatrix and corrplot and this setting doesn't change a behavior of corrplot.
Suggestion for a better solution: Add the line of code set(hS,'Color',[0 0.4470 0.7410]) to the function plotmatrix. This will make not only corrplot faster, but also any other possible combinations of plotmatrix and get functions called like this:
h = plotmatrix(A);
% set(h,'Color',[0 0.4470 0.7410])
for k = 1:length(h(:))
get(h(k),'Color');
end
General
I keep getting this error message when trying to run my code, I'm confident my wiring is correct and I do not know what this error means-
Library 'Servo' is not uploaded to the board. Clear the current Arduino object and recreate it to include the appropriate library. For a list of available libraries, type 'listArduinoLibraries'.
here is my code
a=arduino();
s1 = servo(a, 'D9', 'MinPulseDuration', 700*10^-6, 'MaxPulseDuration', 2300*10^-6);
writePosition(s1,0);
userResponse = "yes";
while userResponse == "yes"
chicken = input("Insert your resistor");
voltage = readVoltage(a, "A0");
if voltage < 1.67155
resistor = "47k";
writePosition(s1,0.25);
minR = 47000 * 0.95;
maxR = 47000 * 1.05;
elseif voltage < 3.53128
resistor = "10k";
writePosition(s1,0.5);
minR = 10000 * 0.95;
maxR = 10000 * 1.05;
elseif voltage < 4.69941
resistor = "1k";
writePosition(s1,0.75);
minR = 1000 * 0.95;
maxR = 1000 * 1.05;
else
resistor = "330";
writePosition(s1,1);
minR = 330 * 0.95;
maxR = 330 * 1.05;
end
resistance = voltageToResistance(voltage);
withinTolerance = (resistance >= minR && resistance <= maxR);
disp(resistor)
if withinTolerance == 1
writeDigitalPin(a, "D4", 1);
writeDigitalPin(a, "D5", 0);
%disp("green")
else
writeDigitalPin(a, "D4", 0);
writeDigitalPin(a, "D5", 1);
%disp("Red")
end
userResponse = input("Would you like to check another resistor? ","s");
writePosition(s1,0);
writeDigitalPin(a, "D4", 0);
writeDigitalPin(a, "D5", 0);
end
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Contests
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General
Hello,
What is the difference between a moving angle and a normal angle?
Compute the Rotation about Y-axis over moving angle a = 30°
then
rotation about X-axis of angle β= 45°
What will the code like?
Thank you
General
Engineer
Engineer
Posted on 30 Nov 2023 at 12:13

Error C MEX S-function

Hello there, I have a Amesim Black box model in Simulink. On my desktop, it works well. Also i tried to run on other desktops. Most of them work well. But some of them gives following error: Error in 'Model' while executing C MEX S-function 'Model', (mdlInitializeConditions), at time 0.0. Caused by: in Simcenter Amesim mexfunction: 'Model', Simcenter Amesim fatal error Cannot initialize Simcenter Amesim Model. EXIT This is an urgent case for me. Could you please help me?

Thank you so much.

Generative AI
Kali
Kali
Posted on 30 Nov 2023 at 5:57

Help

Write a matlab script that will print the odd numbers, 1 through 20, in reverse.
I cannot figure out how to do this correctly, please help.
General
Dear Community,
I am trying to perform PowerGUI Loadflow analysis for EV Charging station. The model converges but the load flow vaues on the DC bus is zero. Whether power_loadflow supports Mixed AC/DC load Flow.
Can someone help me by providing guidance on how to preform the same
Regards
Vara
Contests
ABOAJELA
ABOAJELA
Posted on 29 Nov 2023 at 15:53

damping circuit

i need circuti to model wound rotor synchronous machine damping circuit in matlab simulink , is there any one know how to do it
General
when I build the model I get the name mismatch error for two calibratable signals . The signals are in the data dictionary , and I use them in the model by pulling from the dd with the same name . can anyone point me out what possibly cause this error?
General
Ayush
Ayush
Posted on 29 Nov 2023 at 10:06

facing an issue in

we have extracted a .xml file from solidworks to import in matlab, when we tried to import it shows that simscape multibody should be installed and when we tried to install it it shows the message attached below.
we are working on an educational license provided by our university, is it the issue?
General
It is crucial to understand that this expression could be used in problems related to engineering, physics, mathematics, or any other aspect of real life.
Typically, Matlab is used to solve PDE and ODE problems. Perhaps users calculated this term 0^0 incorrectly in the process.
>> % Reviewed by Bewar Yousif Ali
>> % How to fix this problem 0^0 in Matlab !?
>> % Mathematically, x^0=1 if x≠0 is equal 1 else undefined(NaN)
>> 0^0
ans =
1
>> f=@(x,y) x^y;
>> f(0,0)
ans =
1
>> v=[2 0 5 -1];
>> v.^0
ans =
1 1 1 1
Highlights
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Tips: the more you vote, the higher your chance to win.
General
i=dsolve('Dy=-8*y+40*sin(8*t)','y(0)=5')
Warning: Support for character vector or string inputs will be
removed in a future release. Instead, use syms to declare
variables and replace inputs such as dsolve('Dy = -3*y') with syms
y(t); dsolve(diff(y,t) == -3*y). > In dsolve (line 126)
Contests
JAMEEL
JAMEEL
Posted on 24 Nov 2023 at 21:27

Error at , can not run M = A\b;

% Given data
x = [2.0, 3.0, 6.5, 8.0, 12, 15];
f = [14, 20, 17, 16, 23, 125];
% Construct the cubic spline
h = diff(x);
A = zeros(length(x)-2);
for i = 1:length(x)-2
A(i,i) = 2*h(i) + 2*h(i+1);
A(i,i+1) = h(i+1);
A(i+1,i) = h(i);
A(i+1,i+1) = 2*h(i) + h(i+1);
end
b = [6*(f(2)-f(1))/h(1) + 6*(f(3)-f(2))/h(2);
6*(f(4)-f(3))/h(3) + 6*(f(5)-f(4))/h(4)];
M = A\b;
% Evaluate the second derivative at data points
d2f_dx2 = zeros(length(x),1);
for i = 1:length(x)-2
d2f_dx2(i) = M(i);
d2f_dx2(i+1) = M(i) + h(i)*M(i+1);
d2f_dx2(i+2) = M(i) + 2*h(i)*M(i+1) + h(i)*h(i)*M(i+2);
end
% Display second derivatives at data points
disp('Second Derivatives at Data Points:');
disp(d2f_dx2);
General
Sanika Patil
Sanika Patil
Posted on 24 Nov 2023 at 9:22

face recognition GUI

Error using matlab.ui.control.internal.controller.ComponentController/executeUserCallback Error while evaluating Button PrivateButtonPushedFcn.
help to solve this error in face recognition GUI
Contests
i've finished writing the code for my ~masterpiece~ and it doesn't run on the contest new entry page. it runs on matlab on my desktop and in the matlab live editor in my browser, but not where i really need it to. usually it'll draw the first frame the first time i run the code in a new window, but not any subsequent times. whether i hit "run" or "create animation", the screen grays out as it's supposed to, but then returns to normal without generating the first frame or animation.
i'm not getting a timeout warning or any error messages. i timed the code on my laptop and it takes about 100ish seconds to run and generate the animation the first time i run it before clearing everything from my workspace (and then it takes about twice as long each subsequent time, which makes me a bit nervous. can't figure out why this is the case at all!), which is well within the 255 second limit for the contest. as far as i know, the most computationally expensive function i'm using is patch(). i'm pretty close to the character limit, but i don't know if that's part of the problem.
i tried vectorizing some of the code instead of using for loops, which made the code run slightly slower. i tried using a nested function instead of using drawframe() and an auxiliary function, but that didn't help. i tried clearing all variables except f at the end of drawframe() to no avail. i tried using the close command at the start of drawframe(), with similar success. i updated chrome, closed a bunch of windows, tried safari, used my sister's laptop, all with no luck.
has anyone else had this or a similar problem? any advice?
thanks!