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count the frequency that a value occurs in a dataframe column
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Use groupby and count:
In [37]:
df = pd.DataFrame({'a':list('abssbab')})
df.groupby('a').count()
Out[37]:
a
a
a 2
b 3
s 2
[3 rows x 1 columns]
See the online docs: http://pandas.pydata.org/pandas-docs/stable/groupby.html
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Get class name of django model
...rst()
# Get the model name
book._meta.verbose_name
Setting verbose_name and verbose_name_plural is optional. Django will infer these values from the name of the model class (you may have noticed the use of those values in the admin site).
https://docs.djangoproject.com/en/3.0/ref/models/options/...
Same-named attributes in attrs.xml for custom view
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Solution: Simply extract common attributes from both views and add them directly as children of the <resources> node:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<attr name="myattr1" format="string" />
<attr name="myattr2" format="dimension"...
Disabling Chrome Autofill
...rsions you can just put autocomplete="new-password" in your password field and that's it. I've checked it, works fine.
Got that tip from Chrome developer in this discussion:
https://bugs.chromium.org/p/chromium/issues/detail?id=370363#c7
P.S. Note that Chrome will attempt to infer autofill behavior ...
Can I set enum start value in Java?
... just labels for integers.
Java enums are implemented more like classes - and they can even have multiple attributes.
public enum Ids {
OPEN(100), CLOSE(200);
private final int id;
Ids(int id) { this.id = id; }
public int getValue() { return id; }
}
The big difference is that th...
Make absolute positioned div expand parent div height
... width: 145px;
float: left;
}
Finally, add a clearfix to the parent and you're done (see the fiddle for the complete solution).
Generally, as long as the element with absolute position is positioned at the top of the parent element, chances are good that you find a workaround by floating the...
Strange \n in base64 encoded string in Ruby
...he b64encode method is supposed to add a newline for every 60th character, and the example for the encode64 method is actually using the b64encode method.
It seems the pack("m") method for the Array class used by encode64 also adds the newlines. I would consider it a design bug that this is not opt...
Empty set literal?
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@andy That's not an empty set - that's a set containing the number 1. You don't need the trailing comma by the way - that's only required for tuples.
– sepp2k
Jan 19 '15 at 13:12
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Registry Key '…' has value '1.7', but '1.6' is required. Java 1.7 is Installed and the Registry is P
..., but then one of the server admins "updated" our Java to an older version and uninstalled the one we were using. Don't ask me why, I don't know. I re-installed Java 1.7 and uninstalled 1.6 along with the JREs.
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How to give ASP.NET access to a private key in a certificate in the certificate store?
...=> All tasks => Manage private key => Add IIS AppPool\AppPoolName and grant it Full control. Replace "AppPoolName" with the name of your application pool (sometimes IIS_IUSRS)
IIS 7.5 Website is running under NETWORK SERVICE. Using Certificates MMC, added "NETWORK SERVICE" to Full Trust on ...