Mathematical software – testing whether the polynomial is in the algebra of other polynomials

A collection $ Sigma $ of polynomials is an algebra if: (1) $ lambda f + eta g in Sigma $ for each $ f, g in Sigma, lambda, eta in mathbb {R} $ and 2) $ f, g in Sigma $ implied $ fg in Sigma $, We say that $ P $ is in the algebra of $ {P_1, dots, P_n } $ if $ P $ is contained in the smallest algebra $ P_1, dots, P_n $,

I wondered if there was any way in computer math software to check if there was one $ P $ like in the algebra of a given collection $ P_1, dots, P_n $,

example: to take $ n ge 1 $ and let $ P_1 = x_1 + points + x_n, P_2 = x_1 ^ 2 + points + x_n ^ 2, points P_n = x_1 ^ n + points + x_n ^ n $, Then all $ n $ of the following symmetric functions are in the algebra of $ P_1, dots, P_n $: $$ x_1 + dots + x_n $$ $$ x_1x_2 + dots + x_ {n-1} x_n $$ $$ x_1x_2x_3 + dots + x_ {n-2} x_ {n-1} x_n $$ $$ dots $$ $$ x_1 dots x_n $$

I would appreciate any help.

Software installation – Mailutils / ssmtp / postfix cannot be used

It's something I've been struggling with for a few days.

I'm using an Ubuntu 18.4.3 LTS Mini installation.
Where I run PMS.

First I installed the mailutils and ssmtp and after a few minutes everything worked (the mail header stated: (sSMTP sendmail emulation)).

I restarted Ubuntu and after nothing worked I read the 10ish instructions but nothing seems to work.
I removed, automatically removed, deleted, and reinstalled the software.

What appears to be the big problem is mailutils.conf.
Whatever I do, it seems wrong.
I haven't seen the First Installation setup window from the start, and all attempts to repeat it by cleaning, removing, and installing end in the same way.
Nothing after reinstallation.

I tested
dpkg-reconfigure -plow &
The new installation works .. but nothing.

I tested ssmtp, mutt, postfix, all the same result. Well, actually no results when I try to send a test email. (One of two things happens)
1. the terminal just stops (I can press enter or write) but it doesn't do anything until I cancel the process (ctrl-c)
2. The command prompt reappears, it doesn't report what happened, and no email is sent.

I've struggled with it for so long and tested everything I found on forums, but nothing.

This may not be related, but scp and ssh behave that way. Is it possible that I have redirected all of the output to zero or something?

Heeelp ..

Ubuntu 18.04 LAN drivers and some software were suddenly lost for no reason

I'm using Ubuntu 18.04.3, which I installed last November and have not had any problems yet.

About an hour ago after I restarted my PC to clear some of the GPU memory, I found that Google Chrome is missing. I installed this from the .deb file and then found that the LAN menu is also missing and I now have to use WiFi.

I didn't even do a single sudo in this session, just Python and Dota on Steam.

I later found out that Redshift and VSCode are missing in both the terminal and the launcher. I don't know if there is anything else.

The software settings are all secure and solid.

What exactly went wrong here and how can you restore the LAN?

Cryptocurrency Exchange Software – corner for cryptocurrencies

Oodles Scaffold, our turnkey cryptocurrency exchange platform, makes adding a new cryptocurrency an effortless task. Here you can change configurations such as transaction fees, number of confirmations and much more. Our cryptocurrency exchange development services can transform your current financial ecosystem into a new and improved version of itself

Windows – Transfer of the exe file to users without administrator rights outside the network to install the software

I am now at a dead end and need your help. I tried everything I could find on the web, but I couldn't.

I have hundreds of Non-Administrator Domain users working on their Windows 10 laptops outside Our network with No VPN connection to the domain.

I need to give them a file so they can install a small piece of software.

We used to create the function as a script Race like in the AutoIt, compiled it (with the hard-coded credentials inside) and shared the file with external users. You just had to do it.
Neither a perfect nor the safest solution, but it worked for emergencies.

But now those days are over, with user account control and the need for increases, even with registered administrators.

Is there any way to install the software from a non-administrator user who is not in contact with the domain controllers by just running a local script or exe or even msi?

For example, sharing administrative credentials that have been encrypted or compiled in a script, or even character the exe or msi file in the domain so that the Windows operating system can trust it and accept the installation even if it is not in contact with it?

I tried all The AutoIt forums' suggestions tried that not that old schtasks Workaround, RunAs alternatives, etc., but everything needs to be expanded even if it is run with administrator credentials.

There must be a safe way to do this.

Software engineering – question about check out options on the website

I start a shop selling tickets for an outdoor film screening. I'm trying to find a ticket system that fits into the website I created on Wix. The functions for customers should include simple ticket purchases. Gift voucher purchases to redeem a ticket using a code. POS system. For the administrator, I just want to be able to add and manage every show. If we have to cancel, offer the customer a credit or a transfer ticket for another exhibition. Does anyone know of a service that does this? seems to have a good system. Does anyone know what software or service they are using?

ERP software for steelmaking-KnowIT-ERP – everything else


To ensure that projects meet specifications and are delivered on time and on budget, many metalworking manufacturers use software solutions to support project management.our erp software for metal processingon Industry touches every part of the business to optimize operations and get a 360-degree view of individual projects as well as overall financial and operational results. Know it erp to the Metalworking The industry integrates data and processes to give you a better overview of your customer needs, production processes and the extended supply chain. With them you can react quickly to changing product mixes of customers and shorter lead times. KnowIT can help companies in the metalworking industry to significantly improve their production and profitability. This includes:

Metalworking Characteristics:

1. Quote and estimate,

Second Purchase requisitions, supplier requests for offers (RFQs) and purchase ordersr

Third Work order management tools that can move a project from job to job without having to re-enter or resubmit.

4th An intuitive and easy-to-use interface that requires minimal training to get your team up and running quickly.

5th Dimension inventory tracking,

6th Product configuration,

7th MRP,

8th. Reject estimation and "drop" management,

9th Orders are displayed with dimensional tolerance, ID / OD maximum weights, etc.

10th Barcode Transaction System (for workers and materials) product configuration,

11th Cost accounting (maintain material, work, external services and other charges separately),

12th Integrated quality management,

13th production control,

14th Lean scheduling for on-time delivery,

15th CRM functions (Customer Relationship Management) with which a customer is accompanied by potential customers through to service and maintenance,


Color Spaces – Is There Free Software To Compare Color Spaces?

You don't need any software to compare gamut coverage

For what it's worth, you can get the three X-Y color coordinates from the monitor manufacturer and the three from the ink manufacturer and draw on plain X-Y coordinate graph paper. Connect the vertices with lines and compare / look at them directly. The two shapes overlap. Parts that are not outside the scope. You can get design specifications for color coordinates for any part, equipment, or material from sensors, dyes, inks, and what you have from the manufacturer.

If you want, you can plot them on ICI Chromaticity Plot full color paper. You look really impressive.

RGB shapes are triangular because they have three peaks, and CMYK shapes are trapezoidal because there are four peaks. There is a tip for each of the pigment axes.

This is not the same as a spectral emission density curve that shows relative responses at different wavelengths.

Strategies for Test Environment Variables – Software Engineering Stack Exchange

I am in the process of implementing an API for the OPTIONS request for a pre-flight check on CORS calls.

The allowed origins host between "local", "test" and "prod" is all different. So I moved this host to a dotenv file.

Now when I create my unit test to check this, there is a problem

Suppose local is localhost: 3000, but test is and prod is

So now the test, the header verified


Is only passed in local.

A few ideas I had and reason why I think they wouldn't cover the cases:

Hard code like above under any environmental condition would leave a failed test in a different environment.

Download the env files and check them, but this is useless as I confirm that the file matches the file.

Load the env file for each env and code the expectation in the assurance. Could work the plan is not to have local or come across in the test.

Virtualization – How do I configure a VM to protect my entire hardware fingerprint from the guest operating system and software?

This question was original. Does Firefox in VM have a sufficiently common fingerprint so that I don't need a browser? in the gate community.

I want to know what a web browser's fingerprint looks like in a VM, though
VM runs a common operating system and has standard system settings. Can be VM
configured to not have a fingerprint of the host computer?

(Here I just want to ask for the fingerprint, ignore IP addresses, web
Scripts and tracking cookies)

Here is the VM software we are discussing, better FOSS, like Virtualbox or qemu.

This question could not only refer to a web browser, but also to other types of software.