ROAR | Robot Open Autonomous | Robotics library

Unsigned integers can be compressed by using "bit-packing" techniques: Within a block of unsigned integers only the significant bits are stored, resulting in data compression when all integers in a block are "small". The method is known as FOR (frame of reference).

There are SIMD libraries that do this very efficiently.

Now I want to use FOR-like techniques to encode signed integers, e.g. from a differenced sequence of unsorted unsigned integers. The sign of each signed integer needs to be stored somewhere, there are two options:

1. Store the signs in a separate block of data. This adds overhead.
2. Store the sign together with the absolute value of each signed integer.

I'm following path 2 right now. The 2-s complement has the sign bit in the msb (most signfificant bit), so that won't work for bit-packing à la FOR. One possibility is to store the sign in the lsb (least significant bit). Storing signed integers this way is very unusual, there are no instruction that support this, as far as I know. The question now is: Can these lsb-signed-integers be encoded/decoded efficiently using SIMD instructions?

I think AVX-512 _mm_testn_epi32_mask can be used to extract the lsb from each uint32, followed by a shift, then two mask_extract of some sort? Quite convoluted.

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start from March 1st, 2021, when I load data to Google BigQuery, I always meet an error as below:

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I've been experimenting with the factory implementation described here:

http://www.nirfriedman.com/2018/04/29/unforgettable-factory/

The example uses "Animal" as a base and "Dog" and "Cat" as the derived classes that are registered with the factory. But now suppose I wanted to add a "Lion" class that derives from Cat... how can I derive from Cat while still registering with the Animal factory? Further, I would like to be able to create a "Cat" factory as well that would let me create object of type "Cat" instead of "Animal". Can this example be adapted to do this?

Here is some code based off the original post that shows what I'm trying to do.

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I am working on a website and have it set to work full screen, but, I wanted to make it responsive. I used a grid and am not sure how this transfers over to responsive. I have the media tags on the bottom of the CSS page and the grid is in the first half of the HTML page. I would like to rearrange the CSS so that when the website is open on the phone that the title is at the top then the image shows up first then some of the article, then another image and then more article.

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I am new to web scraping and using beautiful soup 4. I was trying to get just the text printed from inside the

tags which are nested under a div. I am able to get them to print but the tags still appear and the beautiful soup won't let me use the .text function to extract the text from the paragraph tags. Is there a better way to do this or am I just doing it wrong?

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After upgrading to Spring Boot 2.4.1. I get now an Exception

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Help! I try to update the select statement but it seems to not work here So, let me introduced my table Artists and Songs

Note:I already inserted these table yet

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i'm trying to mix javascript prototype with class based, like this:

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I am almost done with an exercise but need help with the last bit. The premise is to have only a clicked article to be shown out of a list of four articles. I can hide all but the first article and get the heading to show when the respective article is clicked but I'm having trouble with the code to get the actual article to show. Here is an HTML snippet (let me know if you need more):

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