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Is “IF” expensive?
...nation on Cell Performance. Another fun one is this post about branchless selections on the Real Time Collision Detection Blog.
In addition to the excellent answers already posted in response to this question, I'd like to put in a reminder that although "if" statements are considered expensive low...
What is the best project structure for a Python application? [closed]
...se in your projects. (Slight wrinkle: since on Windows, the interpreter is selected by the file extension, your Windows users actually do want the .py extension. So, when you package for Windows, you may want to add it. Unfortunately there's no easy distutils trick that I know of to automate this pr...
How to Update Multiple Array Elements in mongodb
...n the search result to just those that match the conditions for the update selection:
db.collection.aggregate([
{ "$match": { "events.handled": 1 } },
{ "$project": {
"events": {
"$setDifference": [
{ "$map": {
"input": "$events",
...
Why do people write the #!/usr/bin/env python shebang on the first line of a Python script?
...
using env gives maximum flexibility in that the user can select the interpreter to use by changing the PATH. Often this flexibility is not required though and the downside is that linux for example can't use the script name for the name of the process in ps and reverts to "python"....
How do I check if a string contains a specific word?
...sets of functionality into a single multi-purpose function (including with selectable case sensitivity), you could use something like this:
function FindString($needle,$haystack,$i,$word)
{ // $i should be "" or "i" for case insensitive
if (strtoupper($word)=="W")
{ // if $word is "W" th...
Creating a textarea with auto-resize
... observe(text, 'keydown', delayedResize);
text.focus();
text.select();
resize();
}
textarea {
border: 0 none white;
overflow: hidden;
padding: 0;
outline: none;
background-color: #D0D0D0;
}
<body onload="init();">
<textarea rows="1" style="he...
Explaining Apache ZooKeeper
... simple: The server team with 3 servers has the majority and is allowed to select the new leader.
Even if you just have 3 servers and one of them fails the other 2 still form the majority and can agree that one of them will become the new leader.
I realize once you think about it some time and un...
How to print a query string with parameter values when using Hibernate
....jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:70)
5. select memberrole0_.member_id as member_i2_12_0_, memberrole0_.id as id1_12_0_, memberrole0_.id
as id1_12_1_, memberrole0_.member_id as member_i2_12_1_, memberrole0_.role_id as role_id3_12_1_,
role1_.id as id1_17_2_, role1_...
How to use sed to replace only the first occurrence in a file?
... then only looked for starting on the next line. Therefore, both lines are selected in this case, and the s/foo/bar/ substitution is performed on both of them.
sed '1,/foo/ s//bar/' <<<$'1foo\n2foo\n3foo' fails: with sed: first RE may not be empty (BSD/macOS) and sed: -e expression #1, char...
pandas: How do I split text in a column into multiple rows?
...tblocks').tolist()) #group by all but one column
['Seatblocks'] #select the column to be split
.apply(split_series,sep=' ') # split 'Seatblocks' in each group
.reset_index(drop=True,level=-1).reset_index()) #remove extra index created
print(df2)
CustNum CustomerN...