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When I catch an exception, how do I get the type, file, and line number?
...Error:
print(traceback.format_exc())
Output
Traceback (most recent call last):
File "/path/to/file.py", line 51, in <module>
print(4/0)
ZeroDivisionError: division by zero
Process finished with exit code 0
...
How do you execute an arbitrary native command from a string?
...her path\file.ext"'
iex "& $command"
Likely, you could handle nearly all cases by detecting if the first character of the command string is ", like in this naive implementation:
function myeval($command) {
if ($command[0] -eq '"') { iex "& $command" }
else { iex $command }
}
But...
Select by partial string from a pandas DataFrame
...egex search is not required, so specify regex=False to disable it.
#select all rows containing "foo"
df1[df1['col'].str.contains('foo', regex=False)]
# same as df1[df1['col'].str.contains('foo')] but faster.
col
0 foo
1 foobar
Performance wise, regex search is slower than substring s...
How do you clear a slice in Go?
...
It all depends on what is your definition of 'clear'. One of the valid ones certainly is:
slice = slice[:0]
But there's a catch. If slice elements are of type T:
var slice []T
then enforcing len(slice) to be zero, by the a...
Java `final` method: what does it promise?
...method can't be overridden (for object scope) or hidden (for static). This allows the original developer to create functionality that cannot be changed by subclasses, and that is all the guarantee it provides.
This means that if the method relies on other customizable components like non-public fie...
Shards and replicas in Elasticsearch
...e need to create an index.
When you create an index (an index is automatically created when you index the first document as well) you can define how many shards it will be composed of. If you don't specify a number it will have the default number of shards: 5 primaries. What does it mean?
It mean...
Error in plot.new() : figure margins too large in R
I'm new to R but I've made numerous correlation plots with smaller data sets. However, when I try to plot a large dataset (2gb+), I can produce the plot just fine, but the legend doesn't show up. Any advice? or alternatives?
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Posting a File and Associated Data to a RESTful WebService preferably as JSON
...as JSON. Part of this application requires the client to upload a file (usually an image) as well as information about the image.
...
Storing time-series data, relational or non?
... description, the actual PK is (Device, Metric, DateTime). (Please don't call it TimeStamp, that means something else, but that is a minor issue.) The uniqueness of the row is identified by:
(Device, Metric, DateTime)
The Id column does nothing, it is totally and completely redundant.
A...
What is the reason for having '//' in Python? [duplicate]
...
I actually like this style better... I can remember in atleast one language I've used (VB?) the differentiating factor was / vs \ ... but I could never remember which was which!
– Matthew Scharley
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