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How do I create a list of random numbers without duplicates?
I tried using random.randint(0, 100) , but some numbers were the same. Is there a method/module to create a list unique random numbers?
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Plotting a list of (x, y) coordinates in python matplotlib
I have a list of pairs (a, b) that I would like to plot with matplotlib in python as actual x-y coordinates. Currently, it is making two plots, where the index of the list gives the x-coordinate, and the first plot's y values are the a s in the pairs and the second plot's y values are the b s ...
PHP parse/syntax errors; and how to solve them
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What are the syntax errors?
PHP belongs to the C-style and imperative programming languages. It has rigid grammar rules, which it cannot recover from when encountering misplaced symbols or identifiers. It can't guess your coding intentions.
Most importan...
COUNT DISTINCT with CONDITIONS
I want to count the number of distinct items in a column subject to a certain condition, for example if the table is like this:
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Accessing the index in 'for' loops?
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Using an additional state variable, such as an index variable (which you would normally use in languages such as C or PHP), is considered non-pythonic.
The better option is to use the built-in function enumerate(), available in both Python 2 and 3:
for i...
What is code coverage and how do YOU measure it?
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Code coverage is a measurement of how many lines/blocks/arcs of your code are executed while the automated tests are running.
Code coverage is collected by using a specialized tool to instrument the binaries to add tracing calls and run a full set of automated tests agains...
How to read/write from/to file using Go?
I've been trying to learn Go on my own, but I've been stumped on trying read from and write to ordinary files.
8 Answers
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Fastest way to count exact number of rows in a very large table?
I have come across articles that state that SELECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
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What is a .h.gch file?
...compiled header.
If a .gch is not found then the normal header files will be used.
However, if your project is set to generate pre-compiled headers it will make them if they don’t exist and use them in the next build.
Sometimes the *.h.gch will get corrupted or contain outdated information, so...
How do I get a class instance of generic type T?
...> . In a method of Foo , I want to get the class instance of type T , but I just can't call T.class .
21 Answers
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