How should I conceptualize a right fold vs a left fold? - functional-programming

Should I conceptualize a right fold as "folding the list to the right" or as "folding a list from the right"?
In other words, does a right fold go from left-to-right or from right-to-left?

Right fold goes from right to left.
Left fold goes from the left, like you read a text - from left to right.

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how to identify right and left hand handpose tensorflow

I'm using handpose for one of the project. I need to find the right and left hand to implement a feature.
I could find the back and front side of the hand by using the coordinates but with the same logic I failed to figure out it is left or right hand because the backside of the right and front side of the left hand look almost same .How to find right and left hand from the detected landmark.
I could see in mediapipe example model is returning left and right hand labels is there anyway to identify the same using TFJS version ?

Translation of rotated element

I have an object rotated around point (0,0). I can't change the anchor point. The rotation is done by another system and I can't influence that. All I have control of is the position of the element (and I can access the rotation value).
Now, I'd like to adjust the element position to make it appear like it's rotating around a specific pivot point.
How it is:
How I want it to be:
I could be wrong (your description honestly isn't great) but it looks to me like you just want to have the anchor point (that you have no control over) in the center of your image. So you just need to know the anchor point, and then calculate, probably, the top-left corner of your image based on the center of it being at the same point as the anchor. If the anchor point is (a,b), the width and height of your image are w and h, respectively, then the top-left corner of your image should go at the point (a - w/2, b - h/2). That is you need to subtract off half of both dimensions.

CSS direction:rtl and top to bottom?

I'm using the following CSS to read a text from right to left:
.rtl { unicode-bidi:bidi-override;direction:rtl;width:300px;}
<span class="rtl">.tfel οt thgir mοrf daer si txet sihT</span>
It's part of an experimental site that would display all the text in the source code reversed, but readable to users.
It works well if I only have a sentence of text. However, once the length of the text is longer than the size of the element (300px in this case), the order of the sentences no longer works. For instance:
Source:
<div class="rtl"> .skaerb txet eht ,htgnel niatrec a tsaP .yllamron demrof era shpargarap eht rehtehw ees ot secnetnes lareves dedulcni ev'I dna ,tfel ot thgir morf daer si txet sihT</div>
Output:
(since I can't post images, there it is: http://img4.hostingpics.net/pics/990715343.jpg )
As you can see, the first sentence, "This text is read from right to left" is aligned at the bottom, which means the order of the paragraph is wrong.
Is there another way to have to text flow normally from top to bottom and read from right to left?
Thank you
It seems (as I explain in a comment) that you actually want text lines to be laid out bottom to top. There is currently no standard or cross-browser way to achieve that. On IE (version 8 and newer) you can use writing-mode: rl-bt (right to left, bottom to top). You might also wish to set text-align: left, since right-to-left direction implies by default right alignment, which is OK for right-to-left languages, but not so for tricks on writing direction for left-to-right languages.

How do you calculate what side of the screen a div is pointing to when 3D transforms are used?

I have asked this before but my math is so bad I still don't understand. I need to know what side of the screen* (top, left, bottom, right) the arrow is pointing to so I can handle dragging activity inside the divs.
This fiddle (code is a mess and it only works in safari/chrome) illustrates the problem. To be clear, the calculation for where the arrow points should come from the exact center of the cube, not the arrow itself. If you can offer some clues about the math I'll do the work and post it here.
*"Side of the screen" means, what angle it is or what hour it would be pointing to if the screen is a clock.
transform: rotateX(ndeg) rotateY(ndeg) rotateZ(ndeg);
In this example, the arrow is pointing between 4 o'clock and 5 o'clock.

QGridLayout issue

I have a problem with when setting my centralwidget with QGridLayout. I have three widgets in my centralwidget. One is one bar in the top that covers all the horizontal length of the centralwidget and the other two are two frames, one square in the left and other one in the right.
My purpose is that the top bar won't change vertically and the left square can expand both vertical and horizontal, and the right on stays without expansion and always in the right corner of the centralwidget giving the left one space to expand.
The problem is when setting the size policy of the right one. If I put fixed the left one will take all the space.
I don't know if you get the idea. Sorry, this is the best I can explain. I would be very appreciated if you could help me.
I set a max and min length to the right widget and it worked.

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