## blockchain – Could a miner set a maximium transaction fee

Yes, miners can choose exactly what transactions to include in their candidate blocks, including the choice to not include anything at all.

Of course, if a high fee paying transaction is available, and one miner chooses to not include it, other miners still can. This is only untrue if an entire cartel with sufficient hashrate that is actively performing a 51% attack chooses not to include a transaction – in that case, it can be censored as long as the attack lasts.

## content type – How do I make fields for documents but not the doc set they reside in?

I need to be able to create document sets where each document with the doc set has a required field, without requiring that that field be required when the doc set is created.

When I click on “+ New” in our document library, the only option is to create a new document set. This is how we want it, but at the Doc Set level, we only care about a location and borrower name as seen in the following image:

Once we click save, however we need to have a required column (called “Borrower Doc Type”) that ensures users designate what type of borrower document they’re uploading to the document set. This is a Choice column that will be different for each document with in the doc set. We have tried the following:

• adding the custom “Borrower Doc Type” column to the Doc Set as required – This makes it so that the user is prompted to add the “Borrower Doc Type” when the doc set is created, but that is wrong because there is no single Doc Type that applies to the entire Document Set. We just need to know the document type of the files added to the doc set.
• adding the custom “Borrower Doc Type” column to the document library – This ensures that the user doesn’t have to enter the Borrower Doc Type when the document set is created, but it does not make the column required for documents uploaded to the document set.

We’re using SharePoint Online via Office365. I feel like I’m running around in circles trying to figure this out, but I’m positive it should be a simple solution.

## windows 10 – CTRL+C closes OpenSSH’s connection when `XAuthLocation` is set

I’m trying to set up Win32-OpenSSH so that I can automatically x-forward but when I set `XAuthLocation` (to `"C:Progra~1VcXsrvxauth.exe"`) any time I `CTRL+C` it spits out `(process exited with code 4294967295)` and exits. Is there a way to stop this from happening?

Found a similar problem here, but their solution was to not use it: https://github.com/PowerShell/Win32-OpenSSH/issues/1675

## complexity theory – For s set \$Ssubseteq RE\$, so call feature of language \$S=emptyset\$ vs. \$S={emptyset}\$

Assume that all languages are over the alphabet $$Sigma$$. What you have here is a bit of ambiguity in the meaning of $$emptyset$$ (recall that the emptyset is defined w.r.t a universal set, and here $$emptyset$$ is used w.r.t different universal sets). Indeed, $$S = { emptyset}$$ refers the set of languages containing only the empty language, that is, in this case, $$emptysetsubseteq Sigma^*$$. Also, $$S = emptyset$$ refers to the empty set w.r.t to the universal set of all languages, that is, in this case $$emptysetsubseteq 2^{Sigma^*}$$.

As you noted, if $$S = emptyset$$, then $$L_S = { langle Mrangle: L(M)in emptyset} = emptyset in text{R}$$. Now if $$S = { emptyset}$$, then $$L_S = { langle Mrangle: L(M)in {emptyset}} = { langle Mrangle: L(M) = emptyset} = E_{TM}$$ which is known to be in $$text{coRE}setminus text{R}$$.

## 8 – How can I extend the webform #states conditions to save a custom set of conditions for webform fields?

I need to store sets of conditions on the webform field level (these would then be evaluated according to the field’s submitted values within a custom submit callback).

I would like these conditions to be editable on the webform field level just like #states conditions that honour the field type for value ranges, set values, boolean etc:

No new custom state is necessarily needed here as this new type of condition would not be related to interacting fields. I’m merely looking for a way to expand webforms and add a custom field to each element that will allow adding (on the UI) sets of conditions based on its value(s). These sets would be part of the field’s properties and accessible in a validation / submit callback.

## gmail – Set Postfix myorigin to the domain that sent the email for multiple domains (Google Workspace SMTP Relay)

I have a Google Workspace account that has multiple sites running on one user. I have aliases setup for gmail.

I’ve setup a Google Workspace SMTP Relay to send emails from my linux server for systems like WordPress using postfix.

It works fine with postfix and emails get sent. However, the problem is that all emails are being mailed by the default domain of the Google Workspace account, because the myorigin setting points to it, e.g default.com.

Here are my postfix/main.cf settings:

``````myorigin = /etc/mailname
mydestination =  localhost
relayhost = [smtp-relay.gmail.com]:587
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = all
``````

In the file /etc/mailname, default.com is the entry. If I change it to say domain-2.com then emails will be sent from domain-2.com. But all my sites will also send emails from domain-2.com.

What I want to happen is for every email to be mailed by the appropriate domain. So if domain-3’s WordPress sends an email I want it to be mailed by domain-3.com rather than domain-2.com or whatever is in /etc/mailname

Adding multiple domains to the /etc/mailname file doesn’t seem to work.

I also tried

``````myorigin = localhost
myorigin = localdomain
myorigin = localhost.localdomain
``````

How can I accomplish this?

## mariadb – Error: Unknown character set: ‘ascii’

When trying to import a database from a .mysql file, I get an error:

``````ERROR 1115 (42000) at line 24: Unknown character set: 'ascii'
``````

The part the error occurs at is from columns using ASCII:

```````column` varchar(64) CHARACTER SET ascii NOT NULL
``````

I checked in /usr/share/mariadb/charsets/, and ascii.xml is there. ASCII is listed in the Index.xml as well. However, when looking at the database it’s not:

``````MariaDB (db)> show character set;
+---------+------------------+---------------------+--------+
| Charset | Description      | Default collation   | Maxlen |
+---------+------------------+---------------------+--------+
| big5    |                  | big5_chinese_ci     |      2 |
| latin1  |                  | latin1_swedish_ci   |      1 |
| latin2  |                  | latin2_general_ci   |      1 |
| ujis    |                  | ujis_japanese_ci    |      3 |
| sjis    |                  | sjis_japanese_ci    |      2 |
| tis620  |                  | tis620_thai_ci      |      1 |
| euckr   |                  | euckr_korean_ci     |      2 |
| gb2312  |                  | gb2312_chinese_ci   |      2 |
| cp1250  |                  | cp1250_general_ci   |      1 |
| gbk     |                  | gbk_chinese_ci      |      2 |
| utf8    |                  | utf8_general_ci     |      3 |
| ucs2    |                  | ucs2_general_ci     |      2 |
| utf8mb4 | UTF-8 Unicode    | utf8mb4_general_ci  |      4 |
| utf16   | UTF-16 Unicode   | utf16_general_ci    |      4 |
| utf16le | UTF-16LE Unicode | utf16le_general_ci  |      4 |
| utf32   | UTF-32 Unicode   | utf32_general_ci    |      4 |
| binary  |                  | binary              |      1 |
| cp932   |                  | cp932_japanese_ci   |      2 |
| eucjpms |                  | eucjpms_japanese_ci |      3 |
+---------+------------------+---------------------+--------+
19 rows in set (0.000 sec)
``````

At this point, I don’t know what’s wrong or how to get the ASCII character set detected and working.

I am using wodby/mariadb with tag `MARIADB_TAG=10.5-3.9.5`.

## complexity theory – Asymptotic notation between two set of variables

I have problems interpreting the definition of asymptotic notation where the functions involve two different set of variables. I am quite confident with the definition of $$f(n) = O(g(n))$$ and its extension to the multivariable case ($$f(n, m) = O(g(n, m))$$). However I don’t acutally understand the meaning of $$f(n) = O(g(m))$$ since $$f$$ and $$g$$ work with two different variables.

If for exame I have that $$n = O(m)$$, the intuition behind this is that $$m$$ upper bounds $$n$$ but I’m not quite sure how to apply the formal definition of big O. The first idea was to use a dummy function approach by defining $$f(n, m) = n$$ and $$g(n, m) = m$$ but this does not work out well.

Another idea was to assume that both $$n$$ and $$m$$ are function of some unkown variables that depends on the problem at hand. In this case $$n = n(x_1, ldots, x_k)$$, $$m = m(x_1, ldots, x_k)$$ and $$n(x_1, ldots, x_k) = O(m(x_1, ldots, x_k))$$.

Is this right? Am I missing something?

## is it possible to create an avl tree given any set of numbers?

Your question is not the right one.

An AVL tree is a binary tree that has additional properties. First it is a search tree, which means we can easily find each number in the tree. Second it is balanced, meaning that there are no leafs very far form the root. (Formal definitions on request.)

Assume you have a set of $$n$$ numbers in advance, and an arbitrary “empty” binary tree with $$n$$ nodes, you can make the tree into a search tree putting the nodes at a well defined position. So, If you can find an empty tree with AVL structure it is no problem to fill it with the values. And indeed, a completely balanced binary tree, adding nodes level by level, satisfies the requirement of AVL trees.

The proper question is: “can we keep a binary tree in AVL form when the values are added and deleted one by one“. When we can do this we have build a quite efficient data structure for sets of values.

## Understanding the set \$M_1 cap M_2\$

Let $$M_1= lbrace left( begin{matrix} a & b & 0 \ c & d & 0 \ 0 & 0 & f end{matrix} right), a,d,f in mathbb{R}, b = overline{c} rbrace$$ be a subspace of hermitian matrices.

Let $$M_2 = lbrace g lambda g ^{-1}, g in SU(3)rbrace$$ such that $$lambda = diag(ilambda_1,ilambda_2, ilambda_3), lambda_i in mathbb{R}.$$

My first question is how can we describe the intersection of $$M_1$$ and $$M_2$$, in other words what are the matrices $$gin SU(3)$$ s.t $$g lambda g ^{-1} in M_2$$.

My second question is what are the connected components of $$M_1 cap M_2$$ ?