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How to convert a string into double and vice versa?
I want to convert a string into a double and after doing some math on it, convert it back to a string.
12 Answers
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Best documentation for Boost:asio?
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First, I've been using Boost.Asio for quite a while already -- and I share your concern. To address your question:
There really is very scarce documentation about Boost.Asio aside from the introduction and tutorial. I am not the author, but this is mostly because there are just too man...
How can I check if a program exists from a Bash script?
... validate that a program exists, in a way that will either return an error and exit, or continue with the script?
37 Answer...
Simplest two-way encryption using PHP
...m php codebase. So when using the latest version of php (which should be standard) you are not able to use this deprecated function anymore.
– Alexander Behling
Sep 12 '19 at 13:09
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Error: Tablespace for table xxx exists. Please DISCARD the tablespace before IMPORT
I am fairly new to MySQL and I am getting a pretty interesting error on which I cannot find any help via google and the stackoverflow search.
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input type=file show only button
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This answer is so simple and elegant and has worked for all browsers.
– Mike.C.Ford
Mar 19 '15 at 15:55
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How do I execute a stored procedure once for each row returned by query?
...stored procedure that alters user data in a certain way. I pass it user_id and it does it's thing. I want to run a query on a table and then for each user_id I find run the stored procedure once on that user_id
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Can I set background image and opacity in the same property?
I can see in CSS references how to set image transparency and how to set a background image . But how can I combine these two in order to set a transparent background image?
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Difference between Pragma and Cache-Control headers?
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Pragma is the HTTP/1.0 implementation and cache-control is the HTTP/1.1 implementation of the same concept. They both are meant to prevent the client from caching the response. Older clients may not support HTTP/1.1 which is why that header is still in use.
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Asking the user for input until they give a valid response
...put the input method in a while loop. Use continue when you get bad input, and break out of the loop when you're satisfied.
When Your Input Might Raise an Exception
Use try and except to detect when the user enters data that can't be parsed.
while True:
try:
# Note: Python 2.x users s...