## Possible amount of signatures with MuSig

With MultiSig, up to 20 signatures may be used in a treshhold signature scheme (What are the limits of m and n in m-of-n multisig addresses?).

As far as I understand, there should be no hardcoded limit with MuSig, as to the Blockchain every scheme would always look like just one single signature (from one single key-pair), even if in reality those were multiple signatures that just were aggregated into one.

Is there anyhting else that limits the amount of signatures that can be used with MuSig, or is this number of possible signatures essentially infinite?

## java – Architectural design for sending large amount of analytics data from production servers to s3 without impacting request performance

Lets say we have a server getting upto 1000 requests per second, serving them at p99 of 20ms (strong business case for not increasing this latency). The server gc parameters have been carefully tuned for this performance and current latency is already bottlenecked by gc. We want to log structured data related to requests and responses, ideally 100% of it without dropping anything, to S3 in for example gzipped jsonlines format (analytics will be done on this data, each file should be ideally 100MB-500MB in size). Analytics does not have to be realtime. A few hours of delay, for example, is fine. Also the IOUtilization already approaches 100% so writing this data to disk at any time is likely not an option. All code is in Java.

Solution 1:
Use the threads getting and serving requests as producers and have them enqueue each request/response into blocking buffer(s) with error/edge case handling of buffer being full, exception, etc. This way the producer threads dont get blocked no matter what. Then have a consumer threadpool consume from these buffer(s) in a batched way, compress and send to s3. The upside is that it is a simple(ish) solution. The main downside is that all this is done in the same jvm and might increase allocation rate and degrade performance for main requests? I suspect the main source of new object creation might be during serialization to string (is this true?). Putting objects into a fixed queue size or draining to (using drainTo method on BlockingQueue) to an existing collection should not allocate anything new I think.

Solution 2:
Setup a separate service running on the same host (so separate jvm with its own tuned gc if necessary) that exposes endpoints like locaholhost:8080/request for example. Producers send data to these endpoints and all consumer logic lies in this service (mostly same as before). Downside is that this might be more complex. Also sending data, even to localhost, might block the producer thread (whose main job is to serve requests) and decrease throughput per host?

For Solution 1 or 2 are there any Java compatible libraries (producer/consumer libraries or high performance TCP based messaging libraries) that might be appropriate to use instead of rolling my own?

I know these questions can be answered by benchmarking and making a poc, but looking for some direction in case someone has suggestions or maybe a third way I haven’t though of.

## magento2.3.2 – Getting minimum order amount value of shipping method in shipping.html magento 2.3.2

I want to display minimum order amount in custom shipping method in checkout and cart page.

These are the exact files i use for it. The minimum order amount is stored in core_config_data.
How to do it.Which files i have to edit for that? can you show me an example code.

appcodeMagentoCheckoutviewfrontendwebtemplateshipping.html

appcodeMagentoCheckoutviewfrontendwebtemplatecartshipping-rates.html

anybody pls help.

## cognitive load – What’s the rationale behind Paypal’s amount input?

This is something I’ve always wanted to ask because it’s really frustrating for me.

If you use Paypal, you will see that when you try to send money, the Amount `input` requires to enter the cents or decimals. Look at the picture below

In this real case, I had to send \$160. On most apps, you enter \$160. On Paypal you have to enter 16000 or you send \$1.60. I’ve had this error once or twice, and now I’m very careful to double and triple check because I sometimes enter an extra 0.

I’ve never seen this before (although I’ve started to see this AFTER Paypal started to do it ). Based on the principles of intentionality in UX, if I wanted to add decimals, I would use floating point and then add decimals. So I’m wondering why they would do something so confusing and if there is some sort of rationale that I’m not aware of

Also, from a Universal UX theory perspective, this is a fail. Paypal knows my country and my language. So they should know that floating point has a whole different meaning for me (we use commas for decimals). Therefore, it’s an even bigger cognitive load. This is a small consideration in the grand scheme of things, but pretty striking when you consider such an important company.

Anyway, is there some kind of explanation from Paypal or a rationale I’m not getting (maybe because of cross-cultural barriers?)? Or is it just an anti-pattern?

## Which module available in the place of Commerce coupon fixed amount in drupal 8

I have a website in drupal 7 where I am using module Commerce coupon fixed amount

Now I want to migrate my website into Drupal 8 but this module is not available in drupal8.

Which module I need to use in place of this module in Drupal 8

## magento2.2 – how to display custom amount in order summary in admin Magento 2?

I have added a custom fee in the order and displayed a custom fee in the checkout order summary.

Similarly, the Custom fee displayed in the order emails in order total summary.

Now I am trying to show the custom fee in summary on the admin order view page.

I have used the below code to display the custom fee on the admin order view page:

1. sales_order_view.xml

``````<referenceContainer name="order_totals">
</referenceContainer>
``````

2. Totals.php

``````<?php

class Totals extends MagentoFrameworkViewElementTemplate
{

/**
* @var Sivajik34CustomFeeHelperData
*/
protected \$_dataHelper;

/**
* @var MagentoDirectoryModelCurrency
*/
protected \$_currency;

public function __construct(
MagentoFrameworkViewElementTemplateContext \$context,
VendorModuleHelperData \$dataHelper,
MagentoDirectoryModelCurrency \$currency,
array \$data = ()
) {
parent::__construct(\$context, \$data);
\$this->_dataHelper = \$dataHelper;
\$this->_currency = \$currency;
}

/**
* Retrieve current order model instance
*
* @return MagentoSalesModelOrder
*/
public function getOrder()
{
return \$this->getParentBlock()->getOrder();
}

/**
* @return mixed
*/
public function getSource()
{
return \$this->getParentBlock()->getSource();
}

/**
* @return string
*/
public function getCurrencySymbol()
{
return \$this->_currency->getCurrencySymbol();
}

/**
*
*
* @return \$this
*/
public function initTotals()
{
\$this->getParentBlock();
\$this->getOrder();
\$this->getSource();

\$fee = (int) \$this->getSource()->getFee();

if (!\$fee) {
return \$this;
}
\$total = new MagentoFrameworkDataObject((
'code' => 'fee',
'value' => \$this->getSource()->getFee(),
'label' => \$this->_dataHelper->getFeeLabel(),
));

return \$this;
}
}
``````

But the custom fee is not showing on the admin order view page. can anyone suggest where I am wrong?

I followed this tutorial Custom Fee

## Does any prime number belong to at least one set of a minimum of \$3\$ prime numbers separated by the same gap and the same amount of other primes?

I have asked a related question here on math.stackexchange.com. I have received some positive votes and some comments with some references to some relevant questions here on mathoverflow.net.

This information made me wonder about another possibility, in which any prime number greater than $$2$$ belongs to at least one set of a minimum of $$3$$ prime numbers, separated not only by the same gap, but also by the same amount of other primes in between?

As a php web developer, I am limited to php’s capabilities with large calculation.

I have developed the following $$3$$ scripts to test the first $$300$$ primes out of a total list of the first $$1000$$ primes:

Script 1) Check every prime whether $$p+k$$ and $$p+2k$$ are also primes, and whether there are the same amount of other primes separating between the $$3$$ numbers.

Script 2) Check every prime whether $$p-k$$ and $$p-2k$$ are also primes, and whether there are the same amount of other primes separating between the $$3$$ numbers.

Script 3) Check every prime whether $$p-k$$ and $$p+k$$ are also primes, and whether there are the same amount of other primes separating between the $$3$$ numbers.

Examples:

Set Gap primes in between
$$3 , 5 , 7$$ 2 0
$$7 , 13 , 19$$ 6 1
$$23 , 53 , 83$$ 30 7

Out of the first $$300$$ primes, the only prime that came false for all $$3$$ scripts was $$227$$

It might be that the test range of the first $$1000$$ primes is too small, and the only way that $$227$$ can redeem a possibility to belong to such a set, is through the possibility of $$p+k$$ and $$p+2k$$ also being primes in a larger test range (which seems highly unlikely so far).

I have tried searching for $$227$$ on OEIS but couldn’t find it as the beginning of a sequence.

Is it possible that $$227$$ will eventually find its matches? What should I expect in terms of the density of true cases and rarity of false cases (or vice versa)? Should I expect any infinite or finite scenarios?

Any references, relevant information, or examples of other numbers like $$227$$ are appreciated.

## amount of investment

on the testimony of bitcoin champion all the testimonies talk of an initial investment of 100 usd, and when Iam registrating the inicial investment is 200 usd? why is this?
I whant to register buy I justo want to invest 100 usd.