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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 ...
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...
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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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...
Java8: Why is it forbidden to define a default method for a method from java.lang.Object
...ried to write an interface that defines a default version of the toString method. Java tells me that this is forbidden, since methods declared in java.lang.Object may not be default ed. Why is this the case?
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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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how to unit test file upload in django
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From Django docs on Client.post:
Submitting files is a special case. To POST a file, you need only
provide the file field name as a key, and a file handle to the file
you wish to upload as a value. For example:
c = Client()
with open('wishlist.doc') as f...