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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 ...
Access nested dictionary items via a list of keys?
...ataDict, mapList):
return reduce(operator.getitem, mapList, dataDict)
and reuse getFromDict to find the location to store the value for setInDict():
def setInDict(dataDict, mapList, value):
getFromDict(dataDict, mapList[:-1])[mapList[-1]] = value
All but the last element in mapList is need...
How do I add spacing between columns in Bootstrap?
...sistent so that all of your columns line up correctly. To get even spacing and column size I would do the following:
<div class="row">
<div class="col-md-5"></div>
<div class="col-md-5 col-md-offset-2"></div>
</div>
In Bootstrap 4 use: offset-2 or offset-md-2...
Creating and throwing new exception
How I can create and throw a new exception in PowerShell?
1 Answer
1
...
How to pass a URI to an intent?
...re the uri as string
intent.putExtra("imageUri", imageUri.toString());
and then just convert the string back to uri like this
Uri myUri = Uri.parse(extras.getString("imageUri"));
share
|
impro...
What is a vertical tab?
... the default vertical size being one line. I have tested with perl "\013" and the same output occurs. This could be used to do line feed without a carriage return on devices with convert linefeed to carriage-return + linefeed.
...
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?
...
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 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...
Type definition in object literal in TypeScript
...has methods as well as properties? Since the class doesn't get initialized and we only assign properties, calling a method on the class will cause a null exception. Basically, the object we create only 'acts' as the class because we assign its type, but it is not actually an instance of that class. ...