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Remove rows with all or some NAs (missing values) in data.frame
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but using complete.cases is quite a lot more clear, and faster.
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What are the differences between a multidimensional array and an array of arrays in C#?
What are the differences between multidimensional arrays double[,] and array-of-arrays double[][] in C#?
9 Answers
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How to check if a string “StartsWith” another string?
...h.
Once you've shimmed the method (or if you're only supporting browsers and JavaScript engines that already have it), you can use it like this:
"Hello World!".startsWith("He"); // true
var haystack = "Hello world";
var prefix = 'orl';
haystack.startsWith(prefix); // false
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How do you make a HTTP request with C++?
...ith C++? Specifically, I want to download the contents of a page (an API) and check the contents to see if it contains a 1 or a 0. Is it also possible to download the contents into a string?
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What causes a java.lang.ArrayIndexOutOfBoundsException and how do I prevent it?
What does ArrayIndexOutOfBoundsException mean and how do I get rid of it?
25 Answers
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How to parse a CSV file using PHP [duplicate]
... CSV file
http://php.net/manual/en/function.fgetcsv.php
$row = 1;
if (($handle = fopen("test.csv", "r")) !== FALSE) {
while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) {
$num = count($data);
echo "<p> $num fields in line $row: <br /></p>\n";
$row++;
for ($...
Android: How to change CheckBox size?
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You just need to set the related drawables and set them in the checkbox:
<CheckBox
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="new checkbox"
android:background="@drawable/my_checkbox_background"
and...
Replace all elements of Python NumPy Array that are greater than some value
I have a 2D NumPy array and would like to replace all values in it greater than or equal to a threshold T with 255.0. To my knowledge, the most fundamental way would be:
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How to generate keyboard events in Python?
...(1, ctypes.byref(x), ctypes.sizeof(x))
def AltTab():
"""Press Alt+Tab and hold Alt key for 2 seconds
in order to see the overlay.
"""
PressKey(VK_MENU) # Alt
PressKey(VK_TAB) # Tab
ReleaseKey(VK_TAB) # Tab~
time.sleep(2)
ReleaseKey(VK_MENU) # Alt~
if __name__ ...
Given an array of numbers, return array of products of all other numbers (no division)
I was asked this question in a job interview, and I'd like to know how others would solve it. I'm most comfortable with Java, but solutions in other languages are welcome.
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