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How to use the PI constant in C++
I want to use the PI constant and trigonometric functions in some C++ program. I get the trigonometric functions with include <math.h> . However, there doesn't seem to be a definition for PI in this header file.
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How to change the remote a branch is tracking?
... to be set up on a new server, so I created a new remote on my local repo, and pushed to that.
13 Answers
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Apache Tomcat Not Showing in Eclipse Server Runtime Environments
I have tomcat 5.5 installed, running and verifiable at http://localhost:8080/ . The Tomcat menu option appears in the Eclipse menu bar and I can start and stop Tomcat from there. In Eclipse, it does not show as a Server Runtime Environment in Window - Preferences - Server - Runtime Environments, no...
In Rails, how do you render JSON using a view?
Suppose you're in your users controller and you want to get a json response for a show request, it'd be nice if you could create a file in your views/users/ dir, named show.json and after your users#show action is completed, it renders the file.
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How to get the type of a variable in MATLAB?
...mp with the class function to test if the object is specifically that type and not a subclass.
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maxlength ignored for input type=“number” in Chrome
...type="number"> by design.
Depending on your needs, you can use the min and max attributes as inon suggested in his/her answer (NB: this will only define a constrained range, not the actual character length of the value, though -9999 to 9999 will cover all 0-4 digit numbers), or you can use a reg...
Make a float only show two decimal places
...oat];
%.02f tells the formatter that you will be formatting a float (%f) and, that should be rounded to two places, and should be padded with 0s.
E.g.:
%f = 25.000000
%.f = 25
%.02f = 25.00
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127 Return code from $?
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Value 127 is returned by /bin/sh when the given command is not found within your PATH system variable and it is not a built-in shell command. In other words, the system doesn't understand your command, because it doesn't know where to find the binary you're trying to call.
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How to detect that animation has ended on UITableView beginUpdates/endUpdates?
... @MrVincenzo Did you set the completionBlock before beginUpdates and endUpdates like in the snippet?
– Rudolf Adamkovič
Feb 19 '13 at 15:11
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When to use EntityManager.find() vs EntityManager.getReference() with JPA
...nager.getReference(LObj.getClass(), LObj.getId()) to get a database entity and then pass the returned object to be persisted in another table.
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