multivariate computation – Find \$ frac { partial ^ 2 f} { partial x partial y} (0, 0) \$ since \$ lim _ {(x, y) to 0} frac {f ( x, y) – tan {(x)} sin {(y)}} {x ^ 2 + y ^ 2} = 0 \$.

$$f in C ^ 2 ( mathbb {R ^ 2})$$ satisfied $$lim _ {(x, y) to 0} frac {f (x, y) – tan {(x)} sin {(y)}} {x ^ 2 + y ^ 2} = 0$$. Find $$frac { partial ^ 2 f} { partial x partial y} (0, 0).$$

I've tried to deduce something from the limit and the definition of the partial derivatives but without effect.

magento2.3.1 – authorizenet-acceptjs from Magento 2.3.1 does not support partial refunds

After upgrading from version 2.2.7 -> 2.3.1, we managed to move from the authorize.net-based hash direct publication, based on a deprecated authorization, to the SHA-512 signature key method .
The problem with the new authorizenet module is now impossible to create partial refunds.
Looking and comparing with the old module, I found provider / magento / module-authorizenet / Model / Directpost.php: 68 at `protected \$ _canRefundInvoicePartial = true;`

Question: what would be the right way to extend the new authorizenet module to support partial refunds?

Thank you.

Can not solve partial differential equation (DSolve)

I have to solve this PDE analytically. I give the entry as shown on the picture, but when I do not, no solution is generated. Why? Should I give more information?

calculation of variations – Partial differentiation of the homogeneous general function of degree n

Yes $$f$$ is homogeneous of degree $$n$$, $$f (tx, ty) = t ^ {n} f (x, y)$$

watch CA
$$f_ {x} (tx, ty) = t ^ {n-1} f_ {x} (x, y)$$

My proof is a little misleading as follows:
$$u = tx, v = ty quadric f {x} (tx, ty) = frac { partial f (u, v)} { partial u} cdot frac { partial u} { partial x } + frac { partial f (u, v)} { partial v} cdot frac { partial v} { partial x} = f_ {u} (u, v) cdot t$$……. (1)

$$quad quad quad quad quad quad frac { partial} { partial x} (t ​​^ nf (x, y)) = t ^ nf_ {x} (x, y)$$……. (2)

(1) = (2)$$qquad f_ {u} (u, v) = t ^ {n-1} f_ {x} (x, y)$$
$$quad quad quad quad , f_ {u} (tx, ty) = t ^ {n-1} f_ {x} (x, y)$$

On the last line, the note on the left side is supposed to be $$x$$however, I receive $$u$$.

set theory – universal partial order to be counted locally

Call a poset to count locally if all the predecessors of each poset member are to enumerate. Is the following coherent?

There is no locally countable poset $$P$$ of size continuum such that each locally countable poset of size continuum fits into $$P$$?

styling

You can align the center elements relative to their parent.

``````#middle {
left margin: 900px;
top margin: 300 pixels;
}
``````
``````#middle {
position: relative;
left: 50%;
transform: translateX (-50%);
above: 50%;
transform: translateY (50%);
}
``````

designation

In my opinion, for algorithms, it is ok to use short variable names.

``````let first_row = document.getElementsByClassName (& nbsp; row1 & nbsp;);
let second_row = document.getElementsByClassName ('row2');
let third_row = document.getElementsByClassName (& # 39; row3 & # 39;);
let sudoku = [
[first_row[0].value, first_row[1].value, first_row[2].value],
[second_row[0].value, second_row[1].value, second_row[2].value],
[third_row[0].value, third_row[1].value, third_row[2].value]]
``````
``````let r1 = document.getElementsByClassName (& nbsp; row1 & nbsp;);
let r2 = document.getElementsByClassName ('row2');
let r3 = document.getElementsByClassName (& # 39; row3 & # 39;);
let sudoku = [
[r1[0].value, r1[1].value, r1[2].value],
[r2[0].value, r2[1].value, r2[2].value],
[r3[0].value, r3[1].value, r3[2].value]]
``````

tensors – The proof of the partial contravariant derivative is a contravariant vector 4 in Lorentz transformations

The partial contravariant derivative is defined as follows:
$$partial ^ mu = frac { partial} { partial x_ mu}$$
where the index $$mu$$ goes from 0 to 3. A contravariant vector in Lorentz transformation (at least in physics textbooks) is defined as:
$$q ^ mu = Lambda ^ mu _ rho q ^ rho$$

Now, what I do not understand, is why the partial derivative is above a contravariant vector 4 (the contravariant part, not the factor that it is a vector 4).

Partial scaling on Ubuntu 19.04 does not seem to work well

I have recently installed Ubuntu 19.04 mainly because I 'm interested in fractional scaling (though it was experimental).

I connect my laptop to a 1080p TV, the size at 100% is not big enough and everything seems in low resolution (mostly text), so I decided to try the partial scaling. But oddly, the 125% are getting too big and buggy. In reality, there is no difference between 125%, 150%, 175% and 200% in my case.

Has anybody used fractional scaling with good results?

Thank you.

mysql – Dropdown Cascade using Partial View .Net Core

I'm trying to build a DropDown in cascade using Partial view, the problem is that I can not pass the login of first DropDown fill in the second and charge only the related equipment to the first list, could anyone help me with that? Here are my codes:

Index

``````Index

Select PA
@foreach (var pa in ViewBag.ListaPA)
{
appoint
}

@ {
wait Html.RenderPartialAsync ("_ Partial");
}

\$('#ComboPA').on('change', function() {
var paID = \$('#ComboPA option:selected').val();
if (paID != -1){
\$.ajax({
type: 'GET',
url: '@Url.Action("Index", "ExemploPartial")/' + paID,
target: '#ComboEquipamento'
});
}
});
});

``````

Partial view:

``````                @ {
foreach (var equipment in ViewBag.EquipmentPA)
{
@ equipment.Equipment | @ equipment.E_Number
}
}
``````

Controller

``````Public class ExamplePartialController: Controller
{

public IActionResult Index ()
{
return See ();
}
[HttpGet]
public IActionResult Index (int paId)
{
ViewBag.ListaPA = new PAModel (). ListAllApp ();
ViewBag.EquipmentPA = new ExamplePartialModel (). ListEquipmentsPA (paId);
return See ();
}
``````

Model

``````namespace Sync.Models
{
Public class ExamplePartialModel
{
public channel Id {get; together; }
public channel Hardware {get; together; }
public string E_Number {get; together; }
public list ListEquipmentsPA (int paId)
{
Listing list = new list();
ExamplePartialModel item;
DAL objDal = new DAL ();
string sql = \$ "SELECT e.id, and.type, and.numero from equi_type and, equipment e, pa p where e.pa_id = p.id and e.etype_id = and.id and p.id = & # 39 {paId} & # 39; "

DataTable dt = objDal.RetDataTable (sql);
for (int i = 0; i <dt.Rows.Count; i ++)
{
item = new ExamplePartialModel
{
Id = dt.Rows[i]["id"].ToString (),
Equipment = dt.Rows[i]["tipo"].ToString (),
E_Number = dt.Rows[i]["numero"].ToString ()
};