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Installing older version of R package

...ageurl <- "http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz" install.packages(packageurl, repos=NULL, type="source") If this doesn't work for you and you're on Windows, the reason is probably the lack of an appropriate tool chain for building/compiling packages. Normal...
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Python Threading String Arguments

...t list processThread.start() If you notice, from the stack trace: self.__target(*self.__args, **self.__kwargs) The *self.__args turns your string into a list of characters, passing them to the processLine function. If you pass it a one element list, it will pass that element as the first argum...
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adding noise to a signal in python

...umpy as np import matplotlib.pyplot as plt t = np.linspace(1, 100, 1000) x_volts = 10*np.sin(t/(2*np.pi)) plt.subplot(3,1,1) plt.plot(t, x_volts) plt.title('Signal') plt.ylabel('Voltage (V)') plt.xlabel('Time (s)') plt.show() x_watts = x_volts ** 2 plt.subplot(3,1,2) plt.plot(t, x_watts) plt.title...
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multi-step registration process issues in asp.net mvc (split viewmodels, single model)

... send on each request. This model binder will be registered in Application_Start: ModelBinders.Binders.Add(typeof(IStepViewModel), new StepViewModelBinder()); The last missing bit of the puzzle are the views. Here's the main ~/Views/Wizard/Index.cshtml view: @using Microsoft.Web.Mvc @model Wiza...
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Log exception with traceback

...g with the trace information, prepended with a message. import logging LOG_FILENAME = '/tmp/logging_example.out' logging.basicConfig(filename=LOG_FILENAME, level=logging.DEBUG) logging.debug('This message should go to the log file') try: run_my_stuff() except: logging.exception('Got excep...
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Which is faster : if (bool) or if(int)?

... Does this also apply to 64-bit processes, that __int64 is faster than int? Or CPU deals 32-bit integer with 32-bit instruction sets separately? – Crend King Apr 27 '11 at 21:22 ...
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Chrome, Javascript, window.open in new tab

... As of 9/29/2014, latest Firefox ESR and IE 11 open _blank or window.open links in a new window when the js calls use _blank as the window name. Current Chrome isn't that simple. I tested opening a new window passing top, left, width, height, toolbar, location, directories, st...
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How to avoid “if” chains?

...the basic flow, e.g. instead of if (ok) { DoSomething(); } else { _log.Error("oops"); return; } ... you'd use.... if (!ok) { _log.Error("oops"); return; } DoSomething(); //notice how this is already farther to the left than the example above When there is a long series of ...
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Complete Working Sample of the Gmail Three-Fragment Animation Scenario?

...le,move]. Notice that fillAfter(true) is not used anywhere. View2 is right_of View1 and View3 is right_of View2 Having set these rules RelativeLayout takes care of everything else. Animations alter the margins (on move) and [width,height] on scale To access each child (so that you can inflat...
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What is the most accurate way to retrieve a user's correct IP address in PHP?

I know there are a plethora of $_SERVER variables headers available for IP address retrieval. I was wondering if there is a general consensus as to how to most accurately retrieve a user's real IP address (well knowing no method is perfect) using said variables? ...