this is really clear and understandable, thanks man!
@mirkodigiacomo85213 ай бұрын
Hi Mike! Thank you for your videos, which are very helpful. Can you share directly the code somewhere?
@gjcamacho4 ай бұрын
Why was is "11.4 worse than 11.61"? I mean, node 16 has lower cost than node 8, i.e. 11.40 < 11.61. Am I missing something?
@mikewagner12043 ай бұрын
This particular example is a maximization problem.
@gaurithakur22934 ай бұрын
EDIT: i initially thought that shouldn't z-ub be updated as 11.72 after the 7th node when we branch out for the first time? why did we keep it as 11.93 (4th node value)? then i found out that "when we branch from a node with a higher objective function value (z), we typically do not update its z value in the table. Instead, our focus shifts to exploring other branches in search of potentially better solutions. The rationale behind this approach is that the current node’s value already serves as an upper bound for the remaining subproblems. If we encounter a better feasible solution later, we adjust the upper bound (z-ub) accordingly."
@owensgbd45595 ай бұрын
Thanks for this series, it's a great introduction to optimization, and more specifically its application with Pyomo. I have one question : could you explain more in detail the importance of using the energy stored as a variable ? Since it's totally defined by the power sold at time t, I don't see it's relevance, because we could instead ensuring that the intial storage charge state plus the net produced energy is between 0 and S0 (so : for each time step, we could have the following constraint : 0 <= S0 + sum(Qi - Wi) <= S0 for i in range(1, t))
@mustafakivanc19186 ай бұрын
Thanks. I am using gurobi but it says infeasible solution. Why did I not reach the same answer as you did?
@jessereed17367 ай бұрын
these are so helpful, thank you!
@sohailshaikh7867 ай бұрын
Thanks Mike. Can we use glpk instead of cbc?
@sparshanalytics77389 ай бұрын
Great work!! Please watch and subscribe PYOMO WITH INHERITANCE - GEHRING & HOMBERGER'S 200 CUSTOMER INSTANCES kzbin.info/www/bejne/nZLcgmiZmJeipbs
@lrz578910 ай бұрын
Great stuff!
@lukejoel674110 ай бұрын
Thank you for these videos
@tsunningwah347111 ай бұрын
been trying to read some paper but was intimidated by the monstrous notation and formula
@tsunningwah347111 ай бұрын
any. good project regarding to optimization?
@tsunningwah347111 ай бұрын
thanks!
@MsSadriel Жыл бұрын
Thank you so much for this video! It's really helping me remember these concepts, it has been a while😅
@tropicalpenguin9119 Жыл бұрын
wow thank you so much. really i am doing a research project on MIP and this series really helped a LOT
@vijaykumars5041 Жыл бұрын
Thanks for the tutorial mike; it really helped me
@shriyakenkre1474 Жыл бұрын
Hi Mike, thanks for this great series of lectures. I'm following the steps given by you. I just had one doubt - Why have you written 2 different constraints for the energy balance? Why can't we have a single constraint - St - St-1 = Qt - Wt for all t? Why is it only for t>=2? The next constraint is similar to this once so why is it written separately?
@ДмитрийБойко-ч4ц9 ай бұрын
The thing is that there is no variable s0 (not to be confused with parametr S0) because time set T starts with 1. We could have introduced the variable s0 and add the constraint s0=S0 to get rid off constraint number 4 though, but it wouldn't have made much difference. The main point is that we don't have variable s for zeroth time period and we say that at time period 1 energy stored (s1) equals to initial energy level (S0) minus energy sold (w1) plus charge (q1)
@ConorBrr Жыл бұрын
Where do you get the values 12.25 and 12.04?
@uuuummm911 ай бұрын
I guess this is a result of objection function with the current (relaxed) values.
@mariocastrogama Жыл бұрын
hey, Great tutorial. I was looking for something like this and yours was the more clear tutorial. I think you have a bug in line 89. Should the last term not be model.s[t-1] instead of model.S0? Maybe I'm not understanding something.
@teijojuntunen7518 Жыл бұрын
Hi Mario and everyone else who is wondering the same, It is not a bug. The charge_schedule is given as a percentage of S0 (which is here also Smax), so that term gives us the Q(t). (and we already have the s(t-1) in this constraint earlier in the line)
@christianorner8024 Жыл бұрын
This series is a great introduction into linear programming. Exactly what I have been looking for. Thanks a lot for creating it.
@entbaum6300 Жыл бұрын
Great Tutorial! The visualization of the simplex method helps understanding tremendously. i had two university classes sovering simplex, and here it is explained the best way
@whooooooowatch Жыл бұрын
Similar name😂
@whooooooowatch Жыл бұрын
Check out mike wagher
@phantomcamel320 Жыл бұрын
4:10 shouldn't one of the two conditions be different? If y_m >= y_k, shouldn't the other condition be y_n < y_k since we need one variable to take the lower bound, and the other one to take the upper bound?
@mikewagner1204 Жыл бұрын
Yes, you're right! There is a typo in step 4 of the figure. The problem should be divided into (1) ym_i <= floor(yk_i) and (2) yn_i >= ceiling(yk_i)
@florianseibel51 Жыл бұрын
Hi, I have a question. How did you make the diagram with the upper and lower bound over time in 5:03? I can't manage to extract the data from the log and then create a dagram. I would be very happy if you tell me with what command to get the data from the log