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The tilde operator in Python
...ssert ~np.True_ == np.False_
Reversing logical value can be useful sometimes, e.g., below ~ operator is used to cleanse your dataset and return you a column without NaN.
from numpy import NaN
import pandas as pd
matrix = pd.DataFrame([1,2,3,4,NaN], columns=['Number'], dtype='float64')
# Remove...
How do you do a deep copy of an object in .NET? [duplicate]
...work.
Your source file must include the following code:
using System.Runtime.Serialization.Formatters.Binary;
using System.IO;
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When do you use varargs in Java?
...ou consider adding a precondition check if (args.length == 0) throw new RuntimeException("foo"); instead? (Since the caller was violating the contract)
– Micha Wiedenmann
Apr 29 '13 at 14:46
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String is immutable. What exactly is the meaning? [duplicate]
...so "bar" is a reference to the same String instance regardless of how many times it appears in your code.
The "hello" creates one instance that is pooled, and the new String(...) creates a non-pooled instance. Try System.out.println(("hello" == "hello") + "," + (new String("hello") == "hello") + ...
Parse date without timezone javascript
I want to parse date without timezone in JavaScript. I have tried:
12 Answers
12
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How do you get the magnitude of a vector in Numpy?
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mag = np.sqrt(x.dot(x))
Here are some benchmarks:
>>> import timeit
>>> timeit.timeit('np.linalg.norm(x)', setup='import numpy as np; x = np.arange(100)', number=1000)
0.0450878
>>> timeit.timeit('np.sqrt(x.dot(x))', setup='import numpy as np; x = np.arange(100)', num...
Javascript - get array of dates between 2 dates
...e 30 days before where should i change the above code to get only date not time.
– vaibhav kulkarni
Jul 22 '15 at 7:27
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Trim spaces from start and end of string
...cript performance this test is still relevant or reliable as it was at the time of this answer.
– Eduardo
Nov 30 '12 at 10:11
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Java; String replace (using regular expressions)?
...attern? This might be useful if you do replaceAll with the same regex many times.
– qed
Nov 5 '14 at 20:35
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How to count the number of set bits in a 32-bit integer?
...in, producing 8x 4-bit sums. The i - ... optimization isn't possible this time so it does just mask before / after shifting. Using the same 0x33... constant both times instead of 0xccc... before shifting is a good thing when compiling for ISAs that need to construct 32-bit constants in registers s...