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Pandas DataFrame Groupby two columns and get counts
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Followed by @Andy's answer, you can do following to solve your second question:
In [56]: df.groupby(['col5','col2']).size().reset_index().groupby('col2')[[0]].max()
Out[56]:
0
col2
A 3
B 2
C 1
D 3
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Android DialogFragment vs Dialog
...th regards handling events in your fragment there would be various ways of doing it but I simply define a message Handler in my Fragment, pass it into the DialogFragment via its constructor and then pass messages back to my fragment's handler as approprirate on the various click events. Again variou...
Can someone explain collection_select to me in clear, simple terms?
I am going through the Rails API docs for collection_select and they are god-awful.
2 Answers
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How to use an existing database with an Android application [duplicate]
...rivate static String TAG = "DataBaseHelper"; // Tag just for the LogCat window
private static String DB_NAME ="YourDbName"; // Database name
private static int DB_VERSION = 1; // Database version
private final File DB_FILE;
private SQLiteDatabase mDataBase;
private final Context ...
JavaScript: Is there a way to get Chrome to break on all errors?
... some other really useful breakpoint capabilities now, such as breaking on DOM changes or network events.
Normally I wouldn't re-answer a question, but I had the same question myself, and I found this now-wrong answer, so I figured I'd put this information in here for people who came along later in...
PostgreSQL: How to change PostgreSQL user password?
How do I change the password for PostgreSQL user?
17 Answers
17
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What exactly does big Ө notation represent?
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It does not, those variables are a bit confusing, they are unrelated.
– Aaron Robeson
Sep 25 '18 at 21:10
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When to Redis? When to MongoDB? [closed]
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MongoDB doesn't enforce a schema, but I'd like to see a case where someone uses it without a schema...it's all how you define the word schema
– Robbie Guilfoyle
Oct 15 '14 at 19:14
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How to remove all leading zeroes in a string
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@NabeelKhan That would not answer the question, which does not ask to convert the string to an integer. See the comments on Svisstack's answer for why this is not such a great solution.
– lonesomeday
Apr 18 '16 at 8:15
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How to set the UITableView Section title programmatically (iPhone/iPad)?
...ted your UITableView delegate and datasource to your controller, you could do something like this:
ObjC
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
NSString *sectionName;
switch (section) {
case 0:
sectionName = NSLocaliz...