What Have You Done Today - (Computer Version)
- Thread starter tlowr4
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- 11,294
- Sweden
- eran0004
I made an Excel sheet for calculating the air change rate n required to achieve a certain humidity in a room after t hours (because this is what I study at University right now).
What it boils down to is to find the intersection between a linear function
and an exponential function
,
where k is a constant determined by the target humidity, the humidity outdoors, the volume of the room and the humidity production in the room. There is no way to solve this equation algebraically, instead it needs to be solved by numerical analysis and that is what this Excel sheet does.
How it works is that it first determines an interval within which the intersection must be. The maximum value of g is 1, given by
.
That means that any n where f(n) > 1 can be excluded, since the intersection can't possibly be there, and this gives us a maximum value of the interval (namely n = 1/k).
The minimum value could be set to zero, but there is a more accurate way to find a minimum n and that is to look at the derivatives of the functions. Since f is greater than g immediately after the intersection we know that g' must be less than or equal to f' at the intersection. Since f' is a constant, g' is shrinking and f(0) = g(0) = 0 we know that there is only one n where f'(n) = g'(n), and that will be the minimum value for our interval (since any n between 0 and this value would give a g'(n) > f'(n)). So we have:
.
Next step is pretty straightforward, set n to be in the in the middle of the interval and evaluate f(n) - g(n). If the value is greater than zero, the intersection must be to the left of n which makes it the new maximum value for the interval. If the value is less than zero then n is the new minimum value for the interval. Repeat this step to get a more and more precise value for n. After about 50 iterations it gets so close that the computer can't tell the difference anymore (around 15 digits accuracy).
What it boils down to is to find the intersection between a linear function
and an exponential function
where k is a constant determined by the target humidity, the humidity outdoors, the volume of the room and the humidity production in the room. There is no way to solve this equation algebraically, instead it needs to be solved by numerical analysis and that is what this Excel sheet does.
How it works is that it first determines an interval within which the intersection must be. The maximum value of g is 1, given by
That means that any n where f(n) > 1 can be excluded, since the intersection can't possibly be there, and this gives us a maximum value of the interval (namely n = 1/k).
The minimum value could be set to zero, but there is a more accurate way to find a minimum n and that is to look at the derivatives of the functions. Since f is greater than g immediately after the intersection we know that g' must be less than or equal to f' at the intersection. Since f' is a constant, g' is shrinking and f(0) = g(0) = 0 we know that there is only one n where f'(n) = g'(n), and that will be the minimum value for our interval (since any n between 0 and this value would give a g'(n) > f'(n)). So we have:
Next step is pretty straightforward, set n to be in the in the middle of the interval and evaluate f(n) - g(n). If the value is greater than zero, the intersection must be to the left of n which makes it the new maximum value for the interval. If the value is less than zero then n is the new minimum value for the interval. Repeat this step to get a more and more precise value for n. After about 50 iterations it gets so close that the computer can't tell the difference anymore (around 15 digits accuracy).
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- 2,055
- United States
- Brucifxr
- 35,429
- Downtown North Dakota
- Cy-Fi
I received an email this weekend about something I signed up for in April of last year to be notified about when Princeton's IoT Inspector was released. It's been running or a bit now and most things appear pretty normal but there are a few devices that make more contact than you'd think and some devices I can't quite figure out what they are just yet but I'll hunt them down.
- 26,911
- Houston, Texas, USA
- JMarine25
Ever since I got my PlayStation 3 in 2011 or so, I have tried not to use it as my gamepad for my PC. Since I don't really play on my PS3 much anymore, I decide only recently to use my PS3 DualShock to be at least my second gamepad for my PC. My original plan was to use the PS3 controller as my PC controller and my XBOX 360 controller as my controller for Android TV games I play. Sadly, I have struggled trying to get the PS3 controller to work on my PC for games. The controller will have the four lights on, signaling it is waiting to be paired with a certain player. The controller is recognized by the PC. Just that... I have yet to be able to use it.
Even still, what I may ultimately want to do is retire my XBOX 360 controller for PC and use on my Android TV box, only to be replaced by an XBOX One controller for my PC. It is also possible I may consider getting a PS4 controller for my PC, though I am even more uncertain that would work on my PC. I'm sure someone probably already tried this to my knowledge.
Even still, what I may ultimately want to do is retire my XBOX 360 controller for PC and use on my Android TV box, only to be replaced by an XBOX One controller for my PC. It is also possible I may consider getting a PS4 controller for my PC, though I am even more uncertain that would work on my PC. I'm sure someone probably already tried this to my knowledge.
- 5,621
- The US of A
- 26,911
- Houston, Texas, USA
- JMarine25
Good enough. I'll take that into consideration if and when I decide to buy a new controller. It isn't likely I will get either an XBOX One or a PlayStation 4, but I can use their controllers. So I'll be sure to weigh my options. Then too, I always have praised the XBOX One controller for being crazy comfortable. I wanted to get the XB1 controller over the PS4. Also with the PS4 controller, I don't know how using the touchpad would work. When I used to play on the OUYA, that controller had a touchpad to it. So I don't know how the PS4's touchpad would work with gaming.
I still will take any advice you all might give to me.
I still will take any advice you all might give to me.
- 1,970
- Adelaide
I know it's been deprecated, but I've been using ScpToolkit to use my DS3 on my PC for the past few years. Never had any problems with it, it even works with my USB Bluetooth adaptor.
- 1,400
- Pennsylvania
- Drex125
- ScoobyMcPancake
Between the PS3 and 4 controllers the PS4 one is a lot easier to get working in my experience, it will work natively with steam games most of the time, and I use DS4Windows for anything that doesn't. Though given the choice an XBOX controller would still be the better option probably.
- 11,294
- Sweden
- eran0004
I programmed a little probability calculator to solve problems of the kind “what is the probability to roll exactly three sixes if I roll the dice seven times”.
Code:
import math
def fakultet(x):
return math.factorial(x)
def prob(p, n, N):
'''p = probability of the event; n = how many times the event should occur; N = number of rolls'''
k = fakultet(N)/(fakultet(n)*fakultet(N-n))
probability = (p**n)*(1-p)**(N-n)*k
return probability- 11,294
- Sweden
- eran0004
Probability calculator, step two: Building a pandemic simulator.
It's a pretty simple model. Every person has a home (sharing with up to 3 others) and every day they visit up to 4 different public spaces, where they meet between ten and fifty random people. At each place, the probability of infection is calculated. The simulation starts with ten people being infected, and then ten new infections are added each month. During the simulation, various policies can be implemented that has different effects on how the people interact with each other.
I don't know how realistic it is, but it's interesting to play around with the model and see what happens.
It's a pretty simple model. Every person has a home (sharing with up to 3 others) and every day they visit up to 4 different public spaces, where they meet between ten and fifty random people. At each place, the probability of infection is calculated. The simulation starts with ten people being infected, and then ten new infections are added each month. During the simulation, various policies can be implemented that has different effects on how the people interact with each other.
I don't know how realistic it is, but it's interesting to play around with the model and see what happens.
I gotta ask with the XboxONE controller and the PS4, can you use those controllers without the dongles for the PC?
Also, which is the best controller for PC use, for like causal console like gaming?
I got an old-ish Xbox360 and it works fine.... just.... Not entirely sure if I am missing out with the next generation type.
Also, which is the best controller for PC use, for like causal console like gaming?
I got an old-ish Xbox360 and it works fine.... just.... Not entirely sure if I am missing out with the next generation type.
- 9,173
- United Kingdom
- neema_t
The Dualshock 4 is Bluetooth, but support on Windows 10 is a bit weird so you'll need some extra software, I think. Xbox One controllers on the other hand if it's an older model controller or Elite v1 then you need a dongle, the newer controllers and Elite v2 have Bluetooth modes so you don't need dongles for those.
Due to the out-of-the-box support and bluetooth I'd say the Xbox One controllers are the best for use with Windows, of those the Elite v2 controller is going to be the very best but it's really not cheap. I've got an Elite v1 and I love it, it has however started to die of death because the rubber on the inner edge of the grips has started to peel off... I'm hoping they do an Elite v3 for the Series X launch because I'm keen to see what the haptic feedback is like on those.
- 26,911
- Houston, Texas, USA
- JMarine25
You know, based on the responses I've gotten for the XBOX One and PS4 controllers, I think I'm going to get an XBOX One controller (as initially planned) in the future. Preferably, a wired one (I'm old-fashioned). So thanks to all of you for your support. If any of you use a PS4 controller for your PC, can you effectively use the touchpad in games or even for basic PC usage?
- 26,911
- Houston, Texas, USA
- JMarine25
For the first time ever, I sideloaded an Android app today! Never before have I attempted to sideload an Android app. I did so recently by sideloading a game that worked on my Google Nexus Player (the hockey puck-looking Android TV box) but doesn't work on my Xiaomi Mi Box S. The game is "GT Racing 2: The Real Car Experience." I actually got fairly far in that game before I had accidentally had most of my progress deleted using an old save of my game. So I attempted to play this game sideloaded on my Android TV box. I had to jack in my other mouse to access a menu. Unfortunately, the program couldn't connect online. I ended up deleting the game from my Mi Box S afterwards. At least now, though, I can say I successfully sideloaded an Android program. I also know now how to set up for a sideload operation.
I apologize if I am discussing something illegal, but it was something I wanted to share.
I apologize if I am discussing something illegal, but it was something I wanted to share.
- 5,621
- The US of A
Got a new wireless mouse recently since my other one I have had for about 5 years was giving me issues and the scroll wheel barely worked anymore. Adjusted the sensitivity slightly and it's been so much better than my old one. Probably the best mouse I have ever used!
Lately, I have been on a bit of a quest to replace a lot of my old low-quality music I have had for over a decade with ones of far better sound quality and I have been working on it almost relentlessly for a few weeks now. I recently re-ripped a lot of my CD's in iTunes with a higher quality setting than the default one since I had ripped them like that for years before I understood what bitrates were. Not sure why Audacity refused to work for me before, but it seems after I reinstalled Windows 10 a few months ago, it works now. I've been using it constantly lately to inspect the audio and make sure it matches up to what I have currently.
Eventually, I need to get the CD's out of my dad's car and rerip them, but I'll have to do it whenever he's at home.
Lately, I have been on a bit of a quest to replace a lot of my old low-quality music I have had for over a decade with ones of far better sound quality and I have been working on it almost relentlessly for a few weeks now. I recently re-ripped a lot of my CD's in iTunes with a higher quality setting than the default one since I had ripped them like that for years before I understood what bitrates were. Not sure why Audacity refused to work for me before, but it seems after I reinstalled Windows 10 a few months ago, it works now. I've been using it constantly lately to inspect the audio and make sure it matches up to what I have currently.
Eventually, I need to get the CD's out of my dad's car and rerip them, but I'll have to do it whenever he's at home.
- 15,401
- TRAPPIST-1g
- ProjectWHaT
I've been looking at PC parts. I'm planning on building a new one soon since my current one (which is like 6 years old) is getting bit slow in a lot of things that I need to use it for. It's going to be mATX so I can bring it to school. Currently planning on getting the Ryzen 5 3600 with a new B550 board. Too bad all of the power supply prices are wack
- 11,985
- Australia
- I_Grayson_Fox_I
mATX and taking it too school?
I think you mean mITX
I would recommend a Lian Li TU150 case as it does have a handle on it
https://www.pccasegear.com/products/48218/lian-li-pc-tu150-mini-itx-windowless-case-black
https://www.pccasegear.com/products/47471/lian-li-pc-tu150-mini-itx-tempered-glass-case-black
Will recommend the non tempered glass version so the glass doesn't shatter by accident
This also means that you can save money by not getting anything RGB related.
And a Air cooler for the CPU like the be quiet! Dark Rock 4 Cooler will just fit with 5mm room to spare.
- 15,401
- TRAPPIST-1g
- ProjectWHaT
Yeah, mATX. I'm currently looking at the Fractal Design Meshify C Mini. I looked at the dimensions and it doesn't seem too bad to take in the car. If it turns out I can't, it's not a deal breaker tbh. For the cooler, I've currently chosen the Noctua NH-U12S.
Here's my current parts list: https://pcpartpicker.com/user/ProjectWHaT/saved/KYrkXL
- 15,401
- TRAPPIST-1g
- ProjectWHaT
Because of COVID and the imminent release of B550, almost all B450M boards are out of stock or extremely marked up. Additionally, there's only a single (1, one, uno) X570 board for mATX and it has never been in stock since I started considering looking at parts. It's quite a bad time to build a PC. Luckily I seemed to have scored an open-box power supply listed for sale locally that I was able to snag an okay deal on.
- 11,985
- Australia
- I_Grayson_Fox_I
I would spend a little more on the PSU and opt for a full modular one.
Going off the cost of the GPU i take it you're carrying it over.
- 15,401
- TRAPPIST-1g
- ProjectWHaT
- 20,681
- TenEightyOne
- TenEightyOne
I ordered the following PC, should arrive in a couple of days. I got it past Mrs. Ten as a business investment. Hurr hurr.
I was still on a budget for Safety Reasons but I think I did okay for £1300-ish. It'll handle PG and large point clouds better than the ******* I'm running now, that's for sure. By coincidence it should also be much better for MSFS2020. Funny, that.
Thoughts welcome, just in case I've made a huge mistake?
I was still on a budget for Safety Reasons but I think I did okay for £1300-ish. It'll handle PG and large point clouds better than the ******* I'm running now, that's for sure. By coincidence it should also be much better for MSFS2020. Funny, that.
Thoughts welcome, just in case I've made a huge mistake?
Processor (CPU) AMD Ryzen 7 3700X Eight Core CPU (3.6GHz-4.4GHz/36MB CACHE/AM4)
Motherboard ASUS® PRIME B450-PLUS (DDR4, USB 3.1, 6Gb/s) - RGB Ready!
Memory (RAM) 32GB Corsair VENGEANCE DDR4 3000MHz (2 x 16GB)
Graphics Card 8GB NVIDIA GEFORCE RTX 2060 SUPER - HDMI, DP - VR Ready!
1st Storage Drive 1TB PCS 2.5" SSD, SATA 6 Gb (520MB/R, 470MB/W)
1st M.2 SSD Drive 512GB PCS PCIe M.2 SSD (2000 MB/R, 1100 MB/W)
Motherboard ASUS® PRIME B450-PLUS (DDR4, USB 3.1, 6Gb/s) - RGB Ready!
Memory (RAM) 32GB Corsair VENGEANCE DDR4 3000MHz (2 x 16GB)
Graphics Card 8GB NVIDIA GEFORCE RTX 2060 SUPER - HDMI, DP - VR Ready!
1st Storage Drive 1TB PCS 2.5" SSD, SATA 6 Gb (520MB/R, 470MB/W)
1st M.2 SSD Drive 512GB PCS PCIe M.2 SSD (2000 MB/R, 1100 MB/W)
- 11,294
- Sweden
- eran0004
A while ago I programmed a Lindenmayer system tree generator. Today I added a user interface with sliders that will let you adjust the shape of the tree in real time.
