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Find integer index of rows with NaN in pandas dataframe
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And just in case, if you want to find the coordinates of 'nan' for all the columns instead (supposing they are all numericals), here you go:
df = pd.DataFrame([[0,1,3,4,np.nan,2],[3,5,6,np.nan,3,3]])
df
0 1 2 3 4 5
0 0 1 3 4.0 NaN 2
1 3 5 6 NaN 3.0 3
np.where(np.as...
Find duplicate lines in a file and count how many time each line was duplicated?
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This is what I do however algorithmically this is doesnt seem to be the most efficient approach (O(n log n)*avg_line_len where n is number of lines). I'm working on files that are several gigabytes large, so performance is a key issue. I wonder whether there is ...
PostgreSQL Autoincrement
...other integer data type, such as smallint.
Example :
CREATE SEQUENCE user_id_seq;
CREATE TABLE user (
user_id smallint NOT NULL DEFAULT nextval('user_id_seq')
);
ALTER SEQUENCE user_id_seq OWNED BY user.user_id;
Better to use your own data type, rather than user serial data type.
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What's the difference between REST & RESTful
...a dissertation by Roy Fielding, REST is an "architectural style" that basically exploits the existing technology and protocols of the Web.
RESTful is typically used to refer to web services implementing such an architecture.
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T-SQL query to show table definition?
...puters that have only the most bare-bones apps and I have no rights to install studio. But SQLCMD is always an option.
16 ...
How to replace a string in a SQL Server Table Column
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I'd typically add where path like '%oldstring%' if there was a lot of data.
– Derek Tomes
Nov 2 '15 at 20:48
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Add and Remove Views in Android Dynamically?
...app like on the original stock Android contacts screen where you press a small icon on the right side of a field and it adds or deletes a field which consists of a TextView and an editTextView (from what I can see).
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Scatterplot with too many points
...;- data.frame(x = rnorm(5000),y=rnorm(5000))
ggplot(df,aes(x=x,y=y)) + geom_point(alpha = 0.3)
Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hexagonal binning:
ggplot(df,aes(x=x,y=y)) + stat_binhex()
And there is also regula...
Collection was modified; enumeration operation may not execute
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Is that a complete example? I have a class (_dictionary obj below) that contains a generic Dictionary<string,int> named MarkerFrequencies, but doing this didn't instantly solve the crash: lock (_dictionary.MarkerFrequencies) { foreach (KeyValuePair<string, int...
How to get a list of column names on Sqlite3 database?
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PRAGMA table_info(table_name);
will get you a list of all the column names.
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