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python dataframe pandas drop column using int
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You need to identify the columns based on their position in dataframe. For example, if you want to drop (del) column number 2,3 and 5, it will be,
df.drop(df.columns[[2,3,5]], axis = 1)
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Compare given date with today
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One caution based on my experience, if your purpose only involves date then be careful to include the timestamp. For example, say today is "2016-11-09". Comparison involving timestamp will nullify the logic here. Example,
// input
$var...
Cannot add or update a child row: a foreign key constraint fails
...date a row to table2 that does not have a valid value for the UserID field based on the values currently stored in table1. If you post some more code I can help you diagnose the specific cause.
share
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Converting a String to DateTime
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Since you are handling 24-hour based time and you have a comma separating the seconds fraction, I recommend that you specify a custom format:
DateTime myDate = DateTime.ParseExact("2009-05-08 14:40:52,531", "yyyy-MM-dd HH:mm:ss,fff",
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How can I access getSupportFragmentManager() in a fragment?
...) // This will also give you the SupportFragmentManager or FragmentManager based on which Fragment class you have extended - android.support.v4.app.Fragment OR android.app.Fragment.
OR
getActivity().getSupportFragmentManager();
in your Fragment's onActivityCreated() method and any method that i...
Ruby on Rails generates model field:type - what are the options for field:type?
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That produces app/models/wheel.rb:
class Wheel < ActiveRecord::Base
belongs_to :car
end
And adds the following migration:
class CreateWheels < ActiveRecord::Migration
def self.up
create_table :wheels do |t|
t.references :car
t.timestamps
end
end
def se...
Can't connect to local MySQL server through socket '/var/mysql/mysql.sock' (38)
...w
This will stop the running services before powering down the machine.
Based on Centos, an additional method for getting it back up again when you run into this problem is to move mysql.sock:
mv /var/lib/mysql/mysql.sock /var/lib/mysql/mysql.sock.bak
service mysqld start
Restarting the servi...
I need an unordered list without any bullets
... <li>...</li>
</ul>
http://twitter.github.io/bootstrap/base-css.html#typography
Bootstrap 3 and 4:
<ul class="list-unstyled">
<li>...</li>
</ul>
Bootstrap 3: http://getbootstrap.com/css/#type-lists
Bootstrap 4: https://getbootstrap.com/docs/4.3/content...
Android WebView style background-color:transparent ignored on android 2.2
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This is how you do it:
First make your project base on 11, but in AndroidManifest set minSdkVersion to 8
android:hardwareAccelerated="false" is unnecessary, and it's incompatible with 8
wv.setBackgroundColor(0x00000000);
if (Build.VERSION.SDK_INT >= 11) wv.setLayerTy...
Do you (really) write exception safe code? [closed]
...on, which enables you to write code with transactional semantics, like databases, with commit/rollback features, the commit being the normal execution of the code, throwing exceptions being the rollback.
Then, the "basic" is the very least guarantee you should offer. C++ is a very strong language th...