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Convert a list to a data frame
...hich in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns to factors, to avoid this you can add a parameter to the data.frame() call:
df <- data.frame(matrix(unl...
Unable to execute dex: GC overhead limit exceeded in Eclipse
...4-bit JVM. If you're on a 64 bit JVM, you can safely set it to anything smaller than your RAM size minus overhead for OS/other applications. On a 32 bit VM, you'll want to keep it smaller than about 1500M (on Linux) or 1100M (on Windows) because the VM needs to allocate contiguous address space, a...
When to use SELECT … FOR UPDATE?
... a DML query creates a copy of the record (in one or another way) and generally readers do not block writers and vice versa. For these databases, a SELECT FOR UPDATE would come handy: it would lock either SELECT or the DELETE query until another session commits, just as SQL Server does.
When sh...
How do I Convert DateTime.now to UTC in Ruby?
...ok.
– DanSingerman
Apr 16 '09 at 11:32
2
Oh sweet. So whats the difference between Date, Time an...
What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?
...erated by MSBuild" - Why? You just went on to explain a good reason to manually control it :)
– mo.
Jan 4 '13 at 17:50
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What is the difference between a regular string and a verbatim string?
... = @"C:\myfolder\myfile.txt";
The @ symbol means to read that string literally, and don't interpret control characters otherwise.
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Import module from subfolder
...For example like this PYTHONPATH=.:.. (for *nix family).
Also you can manually add your current directory (src in your case) to pythonpath:
import os
import sys
sys.path.insert(0, os.getcwd())
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Why can tuples contain mutable items?
...way to detect this.
Another insight is that Python's containers don't actually contain anything. Instead, they keep references to other objects. Likewise, Python's variables aren't like variables in compiled languages; instead the variable names are just keys in a namespace dictionary where they ...
how do I query sql for a latest record date for each user
... row number of 1, so the results may be inconsistent. But as long as you really don't care, then this shouldn't be a problem. This can be solved if you add the PK after the date. For example: order by date desc, id desc).
– Andrew
Apr 26 '19 at 21:40
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Format Instant to String
...While this code snippet may solve the question, including an explanation really helps to improve the quality of your post. Remember that you are answering the question for readers in the future, and those people might not know the reasons for your code suggestion.
– Rosário Pe...