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mkdir -p functionality in Python [duplicate]

...ue) The exist_ok parameter was added in Python 3.5. For Python ≥ 3.2, os.makedirs has an optional third argument exist_ok that, when True, enables the mkdir -p functionality—unless mode is provided and the existing directory has different permissions than the intended ones; in that case, OSEr...
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How to make a Java Generic method static?

... you are calling the static method, Greet.sayHello("Bob"); Greet.sayHello(123); JVM interprets it as the following. Greet.<String>sayHello("Bob"); Greet.<Integer>sayHello(123); Both giving the same outputs. Hello Bob Hello 123 ...
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Bundling data files with PyInstaller (--onefile)

... base_path = sys._MEIPASS except Exception: base_path = os.path.abspath(".") return os.path.join(base_path, relative_path) share | improve this answer | ...
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What's the difference between a single precision and double precision floating point operation?

...ch precision they can store the numbers. For example: I have to store 123.456789 One may be able to store only 123.4567 while other may be able to store the exact 123.456789. So, basically we want to know how much accurately can the number be stored and is what we call precision. Quoting @A...
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Why is a div with “display: table-cell;” not affected by margin?

...ss="table"> <div class="row"> <div class="cell">123</div> <div class="cell">456</div> <div class="cell">879</div> </div> </div> CSS .table {display:table;border-collapse:separate;border-spacing:5px;} .row {di...
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Automatically creating directories with file output [duplicate]

... The os.makedirs function does this. Try the following: import os import errno filename = "/foo/bar/baz.txt" if not os.path.exists(os.path.dirname(filename)): try: os.makedirs(os.path.dirname(filename)) except OS...
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Summarizing multiple columns with dplyr? [duplicate]

...brary(dplyr) library(purrrlyr) library(data.table) library(bench) set.seed(123) n <- 10000 df <- data.frame( a = sample(1:5, n, replace = TRUE), b = sample(1:5, n, replace = TRUE), c = sample(1:5, n, replace = TRUE), d = sample(1:5, n, replace = TRUE), grp = sample(1:3, n, replac...
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Retrieving parameters from a URL

... import urlparse url = 'http://example.com/?q=abc&p=123' par = urlparse.parse_qs(urlparse.urlparse(url).query) print par['q'][0], par['p'][0] share | improve this answer ...
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Build the full path filename in Python

... This works fine: os.path.join(dir_name, base_filename + "." + filename_suffix) Keep in mind that os.path.join() exists only because different operating systems use different path separator characters. It smooths over that difference so cross...
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Does Python have “private” variables in classes?

...names the variable. class A: def __init__(self): self.__var = 123 def printVar(self): print self.__var Now, if you try to access __var outside the class definition, it will fail: >>>x = A() >>>x.__var # this will return error: "A has no attribute __var...