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How to overcome TypeError: unhashable type: 'list'
...used to compare dictionary keys during a dictionary lookup quickly.
Internally, hash() method calls __hash__() method of an object which are set by default for any object.
Converting a nested list to a set
>>> a = [1,2,3,4,[5,6,7],8,9]
>>> set(a)
Traceback (most recent call last...
How do I find numeric columns in Pandas?
Let's say df is a pandas DataFrame.
I would like to find all columns of numeric type.
Something like:
11 Answers
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How do you test running time of VBA code?
...Counter. Google it for more info. Try pushing the following into a class, call it CTimer say, then you can make an instance somewhere global and just call .StartCounter and .TimeElapsed
Option Explicit
Private Type LARGE_INTEGER
lowpart As Long
highpart As Long
End Type
Private Declare Fu...
JSTL in JSF2 Facelets… makes sense?
I would like to output a bit of Facelets code conditionally.
3 Answers
3
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Can someone explain the right way to use SBT?
...tarted, and why?
I think the sane point is to build immunity to sbt gradually.
Make sure you understand:
scopes format {<build-uri>}<project-id>/config:key(for task-key)
the 3 flavors of settings (SettingKey, TaskKey, InputKey) - read the section called "Task Keys" in http://www.sc...
How do you Encrypt and Decrypt a PHP String?
... You may also use GCM (which removes the need for a separate MAC). Additionally, ChaCha20 and Salsa20 (provided by libsodium) are stream ciphers and do not need special modes.
Unless you chose GCM above, you should authenticate the ciphertext with HMAC-SHA-256 (or, for the stream ciphers, Poly1305 -...
Compiling with cython and mingw produces gcc: error: unrecognized command line option '-mno-cygwin'
...
It sounds like GCC 4.7.0 has finally removed the deprecated -mno-cygwin option, but distutils has not yet caught up with it. Either install a slightly older version of MinGW, or edit distutils\cygwinccompiler.py in your Python directory to remove all instan...
Cost of len() function
...
Calling len() on those data types is O(1) in CPython, the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComple...
Why does Go have a “goto” statement
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
Trusting all certificates with okHttp
...
Just in case anyone falls here, the (only) solution that worked for me is creating the OkHttpClient like explained here.
Here is the code:
private static OkHttpClient getUnsafeOkHttpClient() {
try {
// Create a trust manager that does not...