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Evaluating a mathematical expression in a string
...ppend(toks[0])
def pushUMinus(self, strg, loc, toks):
if toks and toks[0] == '-':
self.exprStack.append('unary -')
def __init__(self):
"""
expop :: '^'
multop :: '*' | '/'
addop :: '+' | '-'
integer :: ['+' | '-'] '0'..'9'+
...
Sending files using POST with HttpURLConnection
Since the Android developers recommend to use the HttpURLConnection class, I was wondering if anyone can provide me with a good example on how to send a bitmap "file" (actually an in-memory stream) via POST to an Apache HTTP server. I'm not interested in cookies or authentication or anything com...
MPICH vs OpenMPI
Can someone elaborate the differences between the OpenMPI and MPICH implementations of MPI ?
Which of the two is a better implementation ?
...
Why does changing 0.1f to 0 slow down performance by 10x?
... than on normalized floating-point. This is because many processors can't handle them directly and must trap and resolve them using microcode.
If you print out the numbers after 10,000 iterations, you will see that they have converged to different values depending on whether 0 or 0.1 is used.
Here...
What does Docker add to lxc-tools (the userspace LXC tools)?
... "lxc" refers to capabilities of the linux kernel (specifically namespaces and control groups) which allow sandboxing processes from one another, and controlling their resource allocations.
On top of this low-level foundation of kernel features, Docker offers a high-level tool with several powerful...
What is the difference between Google App Engine and Google Compute Engine?
...ine is a Platform-as-a-Service. It means that you simply deploy your code, and the platform does everything else for you. For example, if your app becomes very successful, App Engine will automatically create more instances to handle the increased volume.
Read more about App Engine
Compute Engine ...
Why em instead of px?
I heard you should define sizes and distances in your stylesheet with em instead of in pixels. So the question is why should I use em instead of px when defining styles in css? Is there a good example that illustrates this?
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Android: install .apk programmatically [duplicate]
I made this with help from
Android download binary file problems
and Install Application programmatically on Android .
...
Updating packages in Emacs
... type package-list-packages, which will take you to the *Packages* buffer (and also update the list of packages), and then type U x.
package-refresh-contents unconditionally tries to download a package list from all repos you've added to package-archives; package-archive-contents is non nil if yo...
Difference between DateTime and Time in Ruby
What's the difference between DateTime and Time classes in Ruby and what factors would cause me to choose one or the other?
...