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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...trieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait you experience is Django loading the database rows and creating objects for each one, before returning something you can actually iterate over. Then you have everything in memory, and the resu...
How do I create test and train samples from one dataframe with pandas?
I have a fairly large dataset in the form of a dataframe and I was wondering how I would be able to split the dataframe into two random samples (80% and 20%) for training and testing.
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How does the Comma Operator work
...semicolon. The difference is that two expressions separated by a semicolon form two separate statements, while comma-separation keeps all as a single expression. This is why comma operator is sometimes used in the following scenarios:
C syntax requires an single expression, not a statement. e.g. i...
Difference between UIViewContentModeScaleAspectFit and UIViewContentModeScaleToFill?
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How to convert a byte array to a hex string in Java?
...ere are many unprintable elements. What I need is the exact hexcode in the form of: 3a5f771c
27 Answers
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How to make “if not true condition”?
...ave written).
Also, looking at your code as is, your use of the $( ... ) form of cmd-substitution is to be commended, but think about what is coming out of the process. Try echo $(cat /etc/passwd | grep "sysa") to see what I mean. You can take that further by using the -c (count) option to grep an...
Position geom_text on dodged barplot
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Vertically centering a div inside another div [duplicate]
...lution with the widest support. Table-layout will impact your rendering performance so I would suggest that you use one of the more modern solutions.
Here is an example
Tested in:
FF3.5+
FF4+
Safari 5+
Chrome 11+
IE9+
HTML
<div class="cn"><div class="inner">your content</d...
Checking from shell script if a directory contains files
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This worked for me, but I can't format this d*mn message!!! <br>export tmp=/bin/ls <some_dir>/* 2> /dev/null if [ ! -z "$tmp" ]; then echo Something is there fi
– AndrewStone
May 25 '11 at 20:00
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Benefits of using the conditional ?: (ternary) operator
... Readability in the second example could easily be rectified with better formatting. But, as the OP is recommending, it comes down to readability and terseness versus verbosity.
– Nathan Ernst
Jul 22 '10 at 22:41
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