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Generate a heatmap in MatPlotLib using a scatter data set
I have a set of X,Y data points (about 10k) that are easy to plot as a scatter plot but that I would like to represent as a heatmap.
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ORA-00979 not a group by expression
...Sure, the result for a column not in the GROUP BY would be random, but sometimes you want that. Silly Oracle, you can do this in MySQL/MSSQL.
BUT there is a work around for Oracle:
While the following line does not work
SELECT unique_id_col, COUNT(1) AS cnt FROM yourTable GROUP BY col_A;
You ca...
Using Python 3 in virtualenv
...y and then reuse them in virtualenvs.
Using this technique saves a lot of time spent on fetching packages and installing them, apart from consuming minimal disk space and network bandwidth.
sudo -H pip3 -v install pdbpp
mkvirtualenv -p $(which python3) --system-site-packages <venv-name>
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What are inline namespaces for?
...vector implementation is chosen. If your codebase was written in pre-C++98 times, and you find that the C++98 version of vector is causing trouble for you when you upgrade your compiler, "all" you have to do is to find the references to std::vector in your codebase and replace them by std::pre_cxx_1...
What is a non-capturing group in regular expressions?
How are non-capturing groups, i.e. (?:) , used in regular expressions and what are they good for?
15 Answers
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How to silence output in a Bash script?
I have a program that outputs to stdout and would like to silence that output in a Bash script while piping to a file.
9 An...
Why is there a difference in checking null against a value in VB.NET and C#?
... way was a controversial one. I was not on the language design team at the time but the amount of debate that went into this decision was considerable.
– Eric Lippert
Mar 20 '13 at 15:37
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On EC2: sudo node command not found, but node without sudo is ok
I have just installed nodejs on a new EC2 micro instance.
12 Answers
12
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what is “strict mode” and how is it used?
...se you did not use the keyword "var" to declare the variable.
Most of the time you don't mean to create global variables in the middle of some arbitrary scope, so most of the time that blah = 33 is written it is an error and the programmer didn't actually want it to be a global variable, they meant...
How to perform mouseover function in Selenium WebDriver using Java?
...that's the only way their result can be passed on to moveElement). At that time the second element that you want to find isn't visible yet because the first one still has to be hovered over. To fix this, as you said, you can insert intermediate .perform()s, Then for the second findElement, the first...