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Error when trying to obtain a certificate: The specified item could not be found in the keychain
...esigning my apps, so I deleted all the keys from the keychain. Then I went to Certificate Assistant => Request a certificate from a Certificate Authority (to create CSR for a new certificate).
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Why can't decimal numbers be represented exactly in binary?
There have been several questions posted to SO about floating-point representation. For example, the decimal number 0.1 doesn't have an exact binary representation, so it's dangerous to use the == operator to compare it to another floating-point number. I understand the principles behind floating-po...
How to asynchronously call a method in Java
I've been looking at Go's goroutines lately and thought it would be nice to have something similar in Java. As far as I've searched the common way to parallelize a method call is to do something like:
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How does Google calculate my location on a desktop?
...ve noticed or used the "my location" feature on google maps using your desktop (or none GPS/none mobile device). If you have a browser with google gears (easiest to use is Google Chrome) then you will have a blue circle above the zoom function in Google Maps, when clicked (without being logged into...
What are the relative strengths and weaknesses of Git, Mercurial, and Bazaar? [closed]
...but not quite a first-class citizen. Git exposes hashes as version numbers to users; this provides guarantees (in that a single hash always refers to the exact same content; an attacker cannot modify history without being detected), but can be cumbersome to the user. Git has a unique concept of trac...
General suggestions for debugging in R
...ere are good strategies for debugging in any language, and they apply here too (e.g. read this nice article). For instance, the first thing is to reproduce the problem...if you can't do that, then you need to get more information (e.g. with logging). Once you can reproduce it, you need to reduce i...
Are duplicate keys allowed in the definition of binary search trees?
I'm trying to find the definition of a binary search tree and I keep finding different definitions everywhere.
12 Answers
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How to create Gmail filter searching for text only at start of subject line?
We receive regular automated build messages from Jenkins build servers at work.
3 Answers
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What is the difference between single-quoted and double-quoted strings in PHP?
...s and most escape sequences will not be interpreted. The exception is that to display a literal single quote, you can escape it with a back slash \', and to display a back slash, you can escape it with another backslash \\ (So yes, even single quoted strings are parsed).
Double quote strings will di...
Is there a short cut for going back to the beginning of a file by vi editor?
When reading a long file by vi editor, it would be very nice to get back to the beginning of the file by some short cuts when you really need to do so. Even ctrl + B sometimes is too slow. Does anyone know such a tool?
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