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Making heatmap from pandas DataFrame
I have a dataframe generated from Python's Pandas package. How can I generate heatmap using DataFrame from pandas package.
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How do I add a foreign key to an existing SQLite table?
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SQLite doesn't support the ADD CONSTRAINT variant of the ALTER TABLE command (sqlite.org: SQL Features That SQLite Does Not Implement).
Therefore, the only way to add a foreign key in sqlite 3.6.1 is during CREATE TABLE as follows:
CREATE TABLE child (
id INTEGER PRIMARY KEY,
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How to speed up insertion performance in PostgreSQL
...n the PostgreSQL manual, depesz's excellent-as-usual article on the topic, and this SO question.
(Note that this answer is about bulk-loading data into an existing DB or to create a new one. If you're interested DB restore performance with pg_restore or psql execution of pg_dump output, much of thi...
html (+css): denoting a preferred place for a line break
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By using
span.avoidwrap { display:inline-block; }
and wrapping the text I want to be kept together in
<span class="avoidwrap"> Text </span>
it will wrap first in preferred blocks and then in smaller fragments as needed.
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When should std::move be used on a function return value? [duplicate]
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met save for the fact that the source object is a function parameter,
and the object to be copied is designated by an lvalue, overload
resolution to select the constructor for the copy is first performed as
if the object were designated by an rvalue.
return foo; is a case of NRVO, so cop...
Pipe output and capture exit status in Bash
I want to execute a long running command in Bash, and both capture its exit status, and tee its output.
15 Answers
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How to turn on/off ReactJS 'development mode'?
...he other answer assumes you are using external pre-built files from react, and while correct that is not how most folks are going to or should consume React as a package. Moreover, at this point most every React library and package also relies on the same convention to toggle dev time helpers off du...
Live-stream video from one android phone to another over WiFi
...nternet for days now on how to implement a video streaming feature from an android phone to another android phone over a WiFi connection but I can't seem to find anything useful. I looked on android developers for sample code, stackoverflow, google, android blogs but nothing. All I can find are some...
Setting default values for columns in JPA
Is it possible to set a default value for columns in JPA, and if, how is it done using annotations?
18 Answers
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How do I center text horizontally and vertically in a TextView?
How do I center the text horizontally and vertically in a TextView , so that it appears exactly in the middle of the TextView in Android ?
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