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Questions tagged [zigzag-encoding]

ZigZag encoding maps signed integers to unsigned integers so that numbers with a small absolute value (for instance, -1) have a small variant encoded value too. It does this in a way that "zig-zags" back and forth through the positive and negative integers, so that -1 is encoded as 1, 1 is encoded as 2, -2 is encoded as 3, and so on

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Zig Zag Decoding

In the google protocol buffers encoding overview, they introduce something called "Zig Zag Encoding", this takes signed numbers, which have a small magnitude, and creates a series of unsigned numbers which have a small magnitude. For example Encoded…
Martin
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Google Protocol Buffers: ZigZag Encoding

From "Signed Types" on Encoding - Protocol Buffers - Google Code: ZigZag encoding maps signed integers to unsigned integers so that numbers with a small absolute value (for instance, -1) have a small varint encoded value too. It does this in a way…
Thanatos
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What's the reason behind ZigZag encoding in Protocol Buffers and Avro?

ZigZag requires a lot of overhead to write/read numbers. Actually I was stunned to see that it doesn't just write int/long values as they are, but does a lot of additional scrambling. There's even a loop…
Endrju
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How to reorder/reshape N-D matrix in zigzag manner?

I would like to sort cells of tensor in this way Note, that each cell is not a single value, but a stack of values (DCT components). So, the dimensions of original tensor is not 2D.
Dims
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Bitwise operations, wrong result in Dart2Js

I'm doing ZigZag encoding on 32bit integers with Dart. This is the source code that I'm using: int _encodeZigZag(int instance) => (instance << 1) ^ (instance >> 31); int _decodeZigZag(int instance) => (instance >> 1) ^ (-(instance & 1)); The code…
Fox32
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Who should be credited for VLQ and zig-zag encoding?

I have designed a (rather simple) network protocol which relies heavily on VLQ-coded integers and zig-zag coding (as described by the Protobuf). I learned about these techniques on the Internet and they felt quite obvious to me. However, now I want…
firegurafiku
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Function to Create a Zigzag Array in Python

I'm trying to create an array of positive and negative integers, representing distances north and south of a location - I need to see the elements of the array in zigzag order. This means that the largest member appears first, the smallest member…
HappyHands31
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Keep getting the wrong answer even though the expected output = output (HackerRank) (Python)

I'm on my third day in HackerRank doing the zigzag sequence and although my output is the same as the expected output, it keeps saying I got the wrong answer: Had the same problem with my mock test earlier and am extremely frustrated by this since I…
niconico
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Is there a faster way to do ZigZag encoding in JavaScript that works with large numbers?

I am attempting to perform ZigZag encoding for numbers in JavaScript that are within the safe bounds of JavaScript integers These functions seem to work up to 2^30 - 1 only because JavaScript bit-wise operators only work with 32 bit…
Ryan Peschel
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ZigZag decode/encode in Java

I'm looking for some library which can provide with the functions that can help deconding zig-zag encoded byte array into 2's complement long/int and back. Since ZigZag is used in protobuf I expected that guava has something for it, but googling…
Some Name
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