## Using matlab to solve system of algebraic equations, got no answers

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Use MathJax to format equations. MathJax reference.

## How can I determine the source of this permission message? “bash“ wants access to control “System Events“

I occasionally receive this permissions message in MacOS 10.15.5:

“bash“ wants access to control “System Events“. Allowing control will provide access to documents and data in “System Events“, and to perform actions within that app.

Googling around, PCrisk implies that this could be a virus/adware. That’d be surprising – I’m pretty careful about what I install.

Is there any way to determine which application is attempting to execute a bash command?

Screenshot:

## linux – Management system to database, draw statitistcs, cronjobs, network load etc

I need to organize management system to my client on his server. I want in this system things like:

• show views from database and draw some charts based on it
• show tables from database
• maybe query editor to run custom queries (like phpmyadmin)
• manage cronjobs – similar like ‘crontab -e’ on linux
• some server statitstics – cpu overload, network traffic etc
• maybe some mailing system to generate raports by day and send summary to client

I want run this on VPS server with Ubuntu 16.04 LTS.

My client have several crawlers on server and have some statistics tables on database. The purpose is manage these information and display on something like management system/panel for someone who is not programmer.

I looking something in Google and I found:

• vespa control panel
• icinga2

Another idea is code this in Python/Django, put data via API and organize this system in 100% custom, but it’s cost money and time. The best option for me is something like ‘ready-to-use’ tool/feature.

Anyone can comment on these tools? Will they fulfill their task? Or maybe somebody have another idea?

## filesystems – CENTOS 7.2 + installing docker on OS with XFS file system

We have 12 machines with CentOS 7 servers ( VM servers ) where the root file system is XFS (created with ftype=0, default CentOS setting at the time the system was installed).

And we want to install on each VM server docker service

Unfortunately, the Docker overlay2 storage driver requires that file system to have been created with ftype=1:

One option to change the ftype to 1 is to do the following steps

1. Boot into CentOS-7-x86_64-LiveGNOME-1804.iso.
2. Open a terminal and sudo -s.
3. Scan for LVM volumes: vgscan
4. Change into the appropriate volume group (centos in my case): vgchange -ay centos
5. Scan for the logical volumes in that group: lvscan
6. Create a mount point for the root FS: mkdir /mnt/root
7. Mount the logical volume corresponding to the root FS: mount /dev/centos/root /mnt/root
8. Dump to remote host: xfsdump -J – /mnt/root | ssh ‘cat >/data/rootfs.dump’
9. Unmount the root FS: umount /mnt/root
10. Recreate the root FS: mkfs.xfs -f -n ftype=1 /dev/centos/root
11. Mount the recreated root FS: mount /dev/centos/root /mnt/root
12. Restore from remote host: ssh ‘cat /data/rootfs.dump’ | xfsrestore -J – /mnt/root
13. Reboot. Everything should be as it was before, except xfs_info / should now show ftype=1.

But we want to know what the other alternative for steps 1-13 , because steps 1-13 required downtime on the servers

Is any other approach to change the ftype to 1 ?

For example maybe by adding additional disk to the OS and create xfs file system with ftype=1

## file system – How to get UNC path of folder on phone?

When I plug my (Android 9) phone into my (Windows 10) PC, it appears in the Windows filesystem within This PC and has a (virtual) folder within it called Internal shared storage, with various folders within.

I can copy files/folders to/from there no problem. But if I want to use an application that references a folder (e.g. WinMerge, to check that the files I copied have actually all been copied), when I select the folder on the phone, it gives an error: “Folder Selection. File not found. Check the filename and try again.” If I try and copy the path of the phone’s folder from Windows File Explorer, I simply get This PC(phone)Internal shared storage(folder) which is obviously not a UNC path that any application or the system would recognize (and isn’t).

There must be some UNC representation of the path to a folder on the phone (which Windows uses internally), and a means of determining it. What is it?

An alternative approach would be if there was a way of cajoling Windows to create a ‘mapped drive’ for the phone, in the same way as would happen when plugging in a USB stick (or an older phone or camera). Suggestions in this department also welcome.

## Is there a safety system to prevent overheating?

Is there currently a system in place that prevents overheating. I have recently been having issues with my mobile hotspot and I noticed that the issues I have seem to be when the phone is above 90 degrees F. (Using a battery temperature app).

When the phone is room temperature everything seems to work fine and when it is above 90 I seem to have issues. I thought maybe the wifi chip was having issues, so I manually tethered with USB and continued to have issues. To rule out my laptop, I connected the phone to my router and hardwired in my laptop. I then bought another cell phone which had the same issues. Specifically the issue I was having was full 20 Mbps and then 0 and then 20 and then 0. (Tested with speedtest.net multiple times.) So it appears to be the actual chip that connects to the cell towers. (On both phones it was doing this.)

Is there a safety mechanism in place in the android system that detects that your phone is heating up and begins cycling chips on and off to prevent overheating? I can see how for most activities a normal person wouldn’t notice unless you’re streaming something live with no buffer (ie: remote desktop over hotspot). Actually if it does this it would be almost genius because it wouldn’t need to completely power off. It could just cycle between normal power and lower power which wouldn’t be an issue for 95% of the things you do, it would increase battery life and decrease phone temperature. However, I also would be doing the 5% of the tasks were it is annoying as all get out watching the mouse cursor skip across my screen and watching windows minimize robotically with jerking updates.

## How to make it so the game waits on player input for a dialog system in Godot?

So i have most system set up im just at loss on make it so that the player has to click through the dialog. Currently all the dialog is stored in text files that are read into dictionary’s like so.

var dic = {}

func test():
var index = 1
popup_centered(Vector2(0,2000))
var line = dic(str(index))
\$Text.set_text(line)

dic = {}
var file = File.new()
file.open(filepath, 1)
var index = 1
while not file.eof_reached():
var line = file.get_line()
print("the line:")
print(line)
dic(str(index)) = line
index += 1
file.close()
print(dic)
test()


Where the test function is like i said above i want the code to wait for the players input and print the next line in the dictionary and then close when the dictionary is empty. Being new to Godot i dont know if there is a simple way to do this. Any help is appreciated and thank you in advance.

Also aside, i know there are a lot of plug-ins for Godot that can handle dialog if i download them, but i want to build this myself so i can learn, so please don’t just say use a plug in.

## Matrix multiplication to system of linear equations

I was looking at the Point-n-Perspective Problem and I can’t understand how you go from :
$$begin{bmatrix} 0 & -1 & v \ 1 & 0 & -u \ -v & u & 0 end{bmatrix} begin{bmatrix} p1 & p2 & p3 & p4\ p5 & p6 & p7 & p8\ p9 & p10 & p11 & p12 end{bmatrix} begin{bmatrix} X \ Y \ Z \ 1 end{bmatrix} = begin{bmatrix} 0 \ 0 \ 0 end{bmatrix}$$
to :
$$begin{bmatrix} 0 & -1 & v \ 1 & 0 & -u \ -v & u & 0 end{bmatrix} begin{bmatrix} textbf{M}^T & textbf{0}_{1times4} & textbf{0}_{1times4} \ textbf{0}_{1times4} & textbf{M}^T & textbf{0}_{1times4} \ textbf{0}_{1times4} & textbf{0}_{1times4} & textbf{M}^T end{bmatrix} begin{bmatrix} textbf{p}_1 \ textbf{p}_2 \ textbf{p}_3 end{bmatrix} = begin{bmatrix} 0 \ 0 \ 0 end{bmatrix}$$

where:
$$begin{bmatrix} p1 & p2 & p3 & p4\ p5 & p6 & p7 & p8\ p9 & p10 & p11 & p12 end{bmatrix} = begin{bmatrix} textbf{p}^T_1 \ textbf{p}^T_2 \ textbf{p}^T_3 end{bmatrix}$$ and $$textbf{M} = begin{bmatrix} X \ Y \ Z \ 1 end{bmatrix}$$

Can you help me understand they go from the first equation to the second one?
(Note: Sorry for the bad title)

## Why won’t my SanDisk memory card work on my iMac desktop. My operating system is mac OS Catalina. It works on my Mac Book Pro [closed]

Why won’t my SanDisk memory card work on my iMac desktop. My operating system is mac OS Catalina. It works on my Mac Book Pro.