MATLAB Onramp 14.1 Project- Stellar Motion Task 7

237 views (last 30 days)
Prem Pankaj
Prem Pankaj on 11 Jul 2020
Commented: NITHARSANA on 3 Oct 2025 at 2:42
Modify the Task 2 & 7 section of the script so that it performs the red shift calculation on the second star in spectra, not the sixth.
I have changed s to the second column (s= spectra(:,2)), and that is right.
How do I get the correct values of lambdaHa and speed?
  2 Comments
Divyanshu
Divyanshu on 29 Apr 2025
Modify the Task 2 & 7 section of the script so that it performs the redshift calculation on the second star in spectra, not the sixth.
Divyanshu
Divyanshu on 29 Apr 2025
Did you store the correct wavelength in lambdaHa?
Did you store the correct speed in speed?

Sign in to comment.

Answers (6)

VAIBHAV PANDEY
VAIBHAV PANDEY on 20 Sep 2020
s = spectra(:,2)
[sHa,idx] = min(s)
lambdaHa = lambda(idx)
z = lambdaHa/656.28 - 1
speed = z*299792.458
  6 Comments
patrick
patrick on 25 Jun 2025
É preciso que a variavel s seja prenchida com o valor da 2 coluna antes de fazer a conta
s = spectra(:,2)
[sHa,idx] = min(s)
lambdaHa = lambda(idx)
z = lambdaHa/656.28 - 1
speed = z*299792.458

Sign in to comment.


Othello Deemi
Othello Deemi on 12 Aug 2022
Could some kindly help me with Tasks 2&7 on the MATLAB Onramp on the topic "Project > Stella Motion"?
Here is my answer:
s = spectra(:,2)
[sHa, idx] = min(s)
lambdaHa = lambda(idx)
z = (lambdaHa/656.28) - 1
speed = z*299792.458
I cannot go further beyond this point. Many thanks.

leela krishna
leela krishna on 20 May 2024
[sHa,idx]=min(s)
lambdaHa=lambda(idx)
hold on
x=lambdaHa
y=sHa
plot(x,y,'rs','MarkerSize',8)

Prabhan Purwar
Prabhan Purwar on 14 Jul 2020
Hi,
The correct values for lambdaHa and speed are calculated using Task 4. At every Task whole of the script runs not the portion of the same.
Thanks

PERUMALSAMY ROHANKUMAR
PERUMALSAMY ROHANKUMAR on 1 Feb 2023
[sHa,idx] = min(spectra(:,2))
to
[sHa,idx] = min(spectra)
  3 Comments
Öznur
Öznur on 3 Mar 2024
hold on
plot(lambdaHa,sHa,"rs",'MarkerSize',8)
NITHARSANA
NITHARSANA on 3 Oct 2025 at 2:42

Add an if statement to the for loop body.if speed(v) is less than or equal to 0, create a plot of s against lambda using a dashed line(--). Add the command hold on between the two end keywords so that you only create one plot

Sign in to comment.


duvan
duvan on 26 Aug 2025
Tarea
Modifique la sección Tasks 2 & 7 del script para que realice el cálculo del desplazamiento al rojo con la segunda estrella de spectra en lugar de la sexta.

Categories

Find more on 2-D and 3-D Plots in Help Center and File Exchange

Community Treasure Hunt

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

Start Hunting!