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Check if option is selected with jQuery, if not select a default
...on>
<option value="2">Second</option>
<option value="3">Third</option>
<option value="4">Fourth</option>
</select>
<script type="text/javascript">
$(document).ready(function() {
if (!$("#mySelect option:selected").length) {
$("#mySelec...
How to efficiently build a tree from a flat structure?
...
123
Store IDs of the objects in a hash table mapping to the specific object. Enumerate through all t...
How to upgrade all Python packages with pip?
...
2351
There isn't a built-in flag yet, but you can use
pip list --outdated --format=freeze | grep -...
Integer division: How do you produce a double?
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163
double num = 5;
That avoids a cast. But you'll find that the cast conversions are well-define...
How to keep index when using pandas merge
...merge_on col2
index
a 1 1 1
b 2 3 2
c 3 4 NaN
Note that for some left merge operations, you may end up with more rows than in a when there are multiple matches between a and b. In this case, you may need to drop duplicates.
...
Launching Spring application Address already in use
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edited Nov 9 '19 at 13:46
answered Dec 23 '13 at 21:45
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Approximate cost to access various caches and main memory?
...anyone give me the approximate time (in nanoseconds) to access L1, L2 and L3 caches, as well as main memory on Intel i7 processors?
...
Does Typescript support the ?. operator? (And, what's it called?)
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Update: it is supported as of TypeScript 3.7 and called Optional chaining: https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-7.html#optional-chaining
I can't find any reference to it whatsoever in the TypeScript language specification.
As far...
How can I keep my fork in sync without adding a separate remote?
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edited Apr 2 '19 at 13:40
userJT
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answered...