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Number of unique elements in a series: In [1]: id_numbers = pd.Series([111, 112, 112, 114, 115, 118, 114, 118, 112]) In [2]: id_numbers.nunique() Out[2]: 5 Get unique elements in a series: In [3]: id_numbers.unique() Out[3]: array([111, 112, 114, 115, 118], dtype=int64) In [4]: df = pd.Da...

Ever wanted to call a multicast delegate but you want the entire invokation list to be called even if an exception occurs in any in the chain. Then you are in luck, I have created an extension method that does just that, throwing an AggregateException only after execution of the entire list complete...

Who says you cannot throw multiple exceptions in one method. If you are not used to playing around with AggregateExceptions you may be tempted to create your own data-structure to represent many things going wrong. There are of course were another data-structure that is not an exception would be mor...

CSV(Comma Separated Values) is a simple file format used to store tabular data, such as a spreadsheet. This is a minimal example of how to write & read data in Python. Writing data to a CSV file: import csv data = [["Ravi", "9", "550"], ["Joe", "8...

explode and strstr are simpler methods to get substrings by separators. A string containing several parts of text that are separated by a common character can be split into parts with the explode function. $fruits = "apple,pear,grapefruit,cherry"; print_r(explode(",",$fruits))...

Pass an open file object from Python to C extension code. You can convert the file to an integer file descriptor using PyObject_AsFileDescriptor function: PyObject *fobj; int fd = PyObject_AsFileDescriptor(fobj); if (fd < 0){ return NULL; } To convert an integer file descriptor back ...

The most flexible ways to sort an array is with the sortedArrayUsingComparator: method. This accepts an ^NSComparisonResult(id obj1, id obj2) block. Return Value Description NSOrderedAscending obj1 comes before obj2 NSOrderedSame obj1 and obj2 have no order NSOrdere...

Keyword lists are tuples of key/value, generally used as options for a function call. [{:a, 1}, {:b, 2}] // creates a non-empty keyword list Keyword lists can have the same key repeated more than once. [{:a, 1}, {:a, 2}, {:b, 2}] [{:a, 1}, {:b, 2}, {:a, 2}] Keys and values can be any type: ...

The normal orElse method takes an Object, so you might wonder why there is an option to provide a Supplier here (the orElseGet method). Consider: String value = "something"; return Optional.ofNullable(value) .orElse(getValueThatIsHardToCalculate()); // returns "some...

You can alternatively use an Object Declaration that contains the main function for a Kotlin program. package my.program object App { @JvmStatic fun main(args: Array<String>) { println("Hello World") } } The class name that you will run is the name of you...

Similar to using an Object Declaration, you can define the main function of a Kotlin program using a Companion Object of a class. package my.program class App { companion object { @JvmStatic fun main(args: Array<String>) { println("Hello World") ...

var arr = [1, 2, 3, 4]; Method 1 Creates a new array and overwrites the existing array reference with a new one. arr = []; Care must be taken as this does not remove any items from the original array. The array may have been closed over when passed to a function. The array will remain in mem...

In Aurelia all HTML templates are defined inside of opening and closing <template></template> tags. All of your HTML and Aurelia specific logic goes inside of these template tags and cannot exist outside of them. <template> </template>

import pandas as pd import numpy as np np.random.seed(0) rng = pd.date_range('2015-02-24', periods=10, freq='T') df = pd.DataFrame({'Val' : np.random.randn(len(rng))}, index=rng) print (df) Val 2015-02-24 00:00:00 1.764052 2015-02-24 00:01:00 0.400157 2015-02...

Get width and height: var width = $('#target-element').width(); var height = $('#target-element').height(); Set width and height: $('#target-element').width(50); $('#target-element').height(100);

Get width and height: var width = $('#target-element').innerWidth(); var height = $('#target-element').innerHeight(); Set width and height: $('#target-element').innerWidth(50); $('#target-element').innerHeight(100);

Get width and height (excluding margin): var width = $('#target-element').outerWidth(); var height = $('#target-element').outerHeight(); Get width and height (including margin): var width = $('#target-element').outerWidth(true); var height = $('#target-element').outerHeight(true); Set widt...

From your Mac, download and install Xcode from the Mac App Store following this link. After the installation is complete, open Xcode and select Get started with a Playground: On the next panel, you can give your Playground a name or you can leave it MyPlayground and press Next: Select a locat...

Picasso.with(context) .load("YOUR IMAGE URL HERE") .placeholder(DRAWABLE RESOURCE) // optional .error(DRAWABLE RESOURCE) // optional .resize(width, height) // optional .rotate(degree) // optional .in...

DROP INDEX ix_cars_employee_id ON Cars; We can use command DROP to delete our index. In this example we will DROP the index called ix_cars_employee_id on the table Cars. This deletes the index entirely, and if the index is clustered, will remove any clustering. It cannot be rebuilt without rec...