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Writing a Python list of lists to a csv file

...s pd In [2]: a = [[1.2,'abc',3],[1.2,'werew',4],[1.4,'qew',2]] In [3]: my_df = pd.DataFrame(a) In [4]: my_df.to_csv('my_csv.csv', index=False, header=False) share | improve this answer ...
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What do the terms “CPU bound” and “I/O bound” mean?

...: #define SIZE 1000000000 unsigned int is[SIZE]; unsigned int sum = 0; size_t i = 0; for (i = 0; i < SIZE; i++) /* Each one of those requires a RAM access! */ sum += is[i] Parallelizing that by splitting the array equally for each of your cores is of limited usefulness on common modern d...
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Environment variables for java installation

...ironment variables (== environment variables of type user variables) JAVA_HOME : C:\Program Files\Java\jdk1.8.0_112 JDK_HOME : %JAVA_HOME% JRE_HOME : %JAVA_HOME%\jre CLASSPATH : .;%JAVA_HOME%\lib;%JAVA_HOME%\jre\lib PATH : your-unique-entries;%JAVA_HOME%\bin (make sure that the longish your...
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How to detect if app is being built for device or simulator in Swift

...ect iOS on a desktop architecture like follows #if (arch(i386) || arch(x86_64)) && os(iOS) ... #endif After Swift 4.1 version Latest use, now directly for all in one condition for all types of simulators need to apply only one condition - #if targetEnvironment(simulator) // ...
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What is the easiest way to remove the first character from a string?

... fastest and most readable way of doing things: require 'benchmark' N = 1_000_000 puts RUBY_VERSION STR = "[12,23,987,43" Benchmark.bm(7) do |b| b.report('[0]') { N.times { "[12,23,987,43"[0] = '' } } b.report('sub') { N.times { "[12,23,987,43".sub(/^\[+/, "") } } b.report('gsub') { N.ti...
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How can I sanitize user input with PHP?

..., you must escape the string with MySQL's function for this purpose (mysqli_real_escape_string). (Or, in case of databases, using prepared statements are a better approach, when possible.) Another example is HTML: If you embed strings within HTML markup, you must escape it with htmlspecialchars. Th...
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How to create a density plot in matplotlib?

... Sven has shown how to use the class gaussian_kde from Scipy, but you will notice that it doesn't look quite like what you generated with R. This is because gaussian_kde tries to infer the bandwidth automatically. You can play with the bandwidth in a way by changing the...
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How can I change UIButton title color?

... With Swift 5, UIButton has a setTitleColor(_:for:) method. setTitleColor(_:for:) has the following declaration: Sets the color of the title to use for the specified state. func setTitleColor(_ color: UIColor?, for state: UIControlState) The following Playgro...
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Image Greyscale with CSS & re-color on mouse-over?

...kground: url(http://4.bp.blogspot.com/-IzPWLqY4gJ0/T01CPzNb1KI/AAAAAAAACgA/_8uyj68QhFE/s400/a2cf7051-5952-4b39-aca3-4481976cb242.jpg); } svg image { transition: all .6s ease; } svg image:hover { opacity: 0; } <p>Firefox, Chrome, Safari, IE6-9</p> <img class="grayscale...
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C# pattern to prevent an event handler hooked twice [duplicate]

...ution and the best one (considering performance) is: private EventHandler _foo; public event EventHandler Foo { add { _foo -= value; _foo += value; } remove { _foo -= value; } } No Linq using required. No need to check for null before cancelling a subscrip...