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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
I'm having a little trouble understanding the pass-by-reference properties of data.table . Some operations seem to 'break' the reference, and I'd like to understand exactly what's happening.
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Why use apparently meaningless do-while and if-else statements in macros?
In many C/C++ macros I'm seeing the code of the macro wrapped in what seems like a meaningless do while loop. Here are examples.
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How to convert a PNG image to a SVG? [closed]
How to convert a PNG image to a SVG?
15 Answers
15
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What is this operator in MySQL?
I'm working on code written by a previous developer and in a query it says,
9 Answers
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“is” operator behaves unexpectedly with integers
Why does the following behave unexpectedly in Python?
11 Answers
11
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Git rebase: conflicts keep blocking progress
I have a git branch (called v4), that was made from master just yesterday. There were a couple of changes to master, that I want to get into v4. So, in v4, I tried to do a rebase from master, and one file keeps screwing things up: a one-line text file, that contains the version number. This file ...
What is a stack trace, and how can I use it to debug my application errors?
Sometimes when I run my application it gives me an error that looks like:
7 Answers
7
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const char * const versus const char *?
I'm running through some example programs to refamiliarize myself with C++ and I have run into the following question. First, here is the example code:
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Getting a slice of keys from a map
Is there any simpler/nicer way of getting a slice of keys from a map in Go?
6 Answers
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Using git repository as a database backend
I'm doing a project that deals with structured document database. I have a tree of categories (~1000 categories, up to ~50 categories on each level), each category contains several thousands (up to, say, ~10000) of structured documents. Each document is several kilobytes of data in some structured f...