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How do I check whether a file exists without exceptions?
How do I check if a file exists or not, without using the try statement?
39 Answers
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Replace all elements of Python NumPy Array that are greater than some value
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I think both the fastest and most concise way to do this is to use NumPy's built-in Fancy indexing. If you have an ndarray named arr, you can replace all elements >255 with a value x as follows:
arr[arr > 255] = x
I ran this on my machine with a 500 x 500 random ma...
How to dump a table to console?
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You just have to choose which one suits you best. There are many ways to do it, but I usually end up using the one from Penlight:
> t = { a = { b = { c = "Hello world!", 1 }, 2, d = { 3 } } }
> require 'pl.pretty'.dump(t)
{
a = {
d = {
3
},
b = {
c = "Hello world!"...
How do you merge two Git repositories?
...e
git log <rev> -- README.md
There are more complex solutions like doing this manually or rewriting the history as described in other answers.
The git-subtree command is a part of official git-contrib, some packet managers install it by default (OS X Homebrew).
But you might have to install...
Proper way to wait for one function to finish before continuing?
...r, wait for that function to finish, then continue on. So, for example/pseudo code:
7 Answers
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How do I clear all options in a dropdown box?
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You can use the following to clear all the elements.
var select = document.getElementById("DropList");
var length = select.options.length;
for (i = length-1; i >= 0; i--) {
select.options[i] = null;
}
share
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How to upload a project to Github
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Since I wrote this answer, github released a native windows client which makes all the below steps redundant.
You can also use sourcetree to get both git and mercurial setup on Windows.
Here is how you would do it in Windows:
If you don't have git installed, see this articl...
CSS: fixed position on x-axis but not y?
...hnique using the script also. You can check a demo here too.
JQuery
$(window).scroll(function(){
$('#header').css({
'left': $(this).scrollLeft() + 15
//Why this 15, because in the CSS, we have set left 15, so as we scroll, we would want this to remain at 15px left
});
});...
How do I pass JavaScript variables to PHP?
...e to the current page PHP code... PHP code runs at the server side, and it doesn't know anything about what is going on on the client side.
You need to pass variables to PHP code from the HTML form using another mechanism, such as submitting the form using the GET or POST methods.
<DOCTYPE html...
How do I launch the Android emulator from the command line?
...ssume that you have built your project and just need to launch it, but you don't have any AVDs created and have to use command line for all the actions. You have to do the following.
Create a new virtual device (AVD) for the platform you need. If you have to use command line for creating your AVD,...