atten | Simple attendance system using QR on browser | QRCode Processing library

I have the following XML structure:

I would like to store each value from an array.
For example the form sends me this data:
"attendance"=>{"event_id"=>"6", "member_id"=>["16", "28", "26"]}
I'd like the database to store the data as:

I am having problems with everything about this, it's supposed to be a dictionary and a translator, but I gave up on the translator part. Right now, the program cannot get any entries from the .get() function.

I am trying to draw an Ellipsoid using shaders in Unity

Following the steps
1. I have written a custom shader with the help of some internet tutorial
2. Added the shader on the material
3. Applied that material on the object

So, I´ve been trying to learn how to write UnityCG shaders by watching tutorials and trying to modify those projects on my own afterwards. But every time anything involves Tags {"LightMode" = "X"} my shader just turns invisible or "error magenta", no matter which tag i use it's always one of these two outcomes. I've rummaged through every related term i could think of, and even tried reinstalling Unity in case something was corrupted, but nothing helped.

Here's a shader copied straight from here, no changes made, and doesn't work on my end.

I am using Eigen in a project of mine, and I am running into a strange issue. I have complex sparse matrices A and B (1500x1500 or larger), and am multiplying them together with coefficients.

When A = B, and taking vector x of ones, I expect that

(A-B)*x = 0, (A*B-B*A)*x = 0,

(A*A*B*B - B*B*A*A)*x = 0,

etc. and I do get this result for all these cases. (A.isApprox(B) evaluates to 1 and (A-B).norm() = 0).

However, when I multiply the matrices by doubles, as in

(c1*A*c2*A*d1*B*d2*B - d1*B*d2*B*c1*A*c2*A)*x,

I get a nonzero result, which doesn't make sense to me, as scalars should commute with the matrices. In fact, if I do,

(c1*c2*d1*d2*A*A*B*B - d1*d2*c1*c2*B*B*A*A)*x

I get zero. Any time the coefficients are interspersed in the matrix manipulation, I get a nonzero result.

I am not using any compiler optimizations, etc.

What am I doing wrong here?

Edit: I have worked up a simple example. Maybe I'm missing something dumb, but here it is. This gives me an error of 10^20.

'''

Unity Project, Want to combine these two shaders into one shader to get both of their functionality. One shader is for lighting, the other shader is for rendering better. How do I combine?

While registering/signing up a user, I store data in 3 fields in each users document: Name, email and username. I have a button, pressing which reveals a welcome message as such: "Hellow, (username)", but this fails to read the username of the current user, ie the user that is currently logged in, and instead displays the username of any other random user.

I can read the email of the current user by using Firebase Auth, ie:

When I resize the screen the background color of the div is changed to black (background of div in the next line) instead of maroon. Please refer this jsfiddle link:

[ https://jsfiddle.net/0j2n1s3d/3/ ]