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How to access pandas groupby dataframe by key
...y dictionary / copy of every subdataframe for every group, so will be much more memory-efficient that creating the naive dictionary with dict(iter(gb)). This is because it uses data-structures already available in the groupby object.
You can select different columns using the groupby slicing:
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vertical-align with Bootstrap 3
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Environment variable substitution in sed
... that you can double-quote the entire string (which may make the statement more readable and less error prone).
So if you want to search for 'foo' and replace it with the content of $BAR, you can enclose the sed command in double-quotes.
sed 's/foo/$BAR/g'
sed "s/foo/$BAR/g"
In the first, $BAR w...
Cannot add or update a child row: a foreign key constraint fails
...rID field based on the values currently stored in table1. If you post some more code I can help you diagnose the specific cause.
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Why doesn't java.util.Set have get(int index)?
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Get TFS to ignore my packages folder
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What are the main disadvantages of Java Server Faces 2.0?
...cess validations, conversions, model changes and action invocations in the more complex webapplications. The pain could be softened by adopting a 3rd party library which retains the necessary data in the subsequent request like MyFaces Tomahawk <t:saveState> component, JBoss Seam conversation ...
.NET WPF Remember window size between sessions
...ool - to hold whether the window is maximized or not. If you want to store more information then a different type or structure will be needed.
Initialise the first two to 0 and the second two to the default size of your application, and the last one to false.
Create a Window_OnSourceInitialized e...
Why is String.chars() a stream of ints in Java 8?
... and wanting to print them ultimately, you cannot use method references anymore for printing:
hello.chars()
.forEach(i -> System.out.println((char)i));
Moreover, using method references to your own method do not work anymore! Consider the following:
private void print(char c) {
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What does the filter parameter to createScaledBitmap do?
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