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In Java, what is the best way to determine the size of an object?
...f data, but I want to make sure that I don't read in too many rows of data and cause OutOfMemoryError s. Each row translates into an object. Is there an easy way to find out the size of that object programmatically? Is there a reference that defines how large primitive types and object reference...
Difference between '..' (double-dot) and '…' (triple-dot) in range generation?
I've just started learning Ruby and Ruby on Rails and came across validation code that uses ranges:
5 Answers
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How to change ProgressBar's progress indicator color in Android
.... This is from the layout that has the progress bar:
<ProgressBar
android:id="@+id/ProgressBar"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:indeterminate="false"
android:maxHeight="10dip...
Selecting multiple columns in a pandas dataframe
...1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of the ...
How can you determine how much disk space a particular MySQL table is taking up?
...length) tablesize
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';
KILOBYTES
SELECT (data_length+index_length)/power(1024,1) tablesize_kb
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';
MEGABYTES
SELECT (data_length+index_len...
How to require a fork with composer
...
The most common (and easier) way of doing it is using a VCS repository.
All you have to do is add your fork as a repository and update the
version constraint to point to your custom branch. Your custom branch
name must be prefixed wit...
Strings as Primary Keys in SQL Database [closed]
I am not very familiar with databases and the theories behind how they work. Is it any slower from a performance standpoint (inserting/updating/querying) to use Strings for Primary Keys than integers?
...
Git: can I suppress listing of 'modified content'/dirty submodule entries in status, diff, etc?
...module within the .gitmodules file.
Just today I encountered this problem and immediately wrote an article in my blog about it after finding a solution: How to ignore changes in git submodules
The gist of it:
Once you added a submodule there will be a file named .gitmodules in the root of your...
Could not open a connection to your authentication agent
...h-agent?
You might need to start ssh-agent before you run the ssh-add command:
eval `ssh-agent -s`
ssh-add
Note that this will start the agent for msysgit Bash on Windows. If you're using a different shell or operating system, you might need to use a variant of the command, such as those listed ...
How do I pass a class as a parameter in Java?
Is there any way to pass class as a parameter in Java and fire some methods from that class?
10 Answers
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