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Non-static method requires a target

I have a controller action that works fine on Firefox both locally and in production, and IE locally, but not IE in production. Here is my controller action: ...
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instantiate a class from a variable in PHP?

...you work with namespace, put the current namespace into the string: $var = __NAMESPACE__ . '\\' . $var . 'Class'; – bastey Sep 2 '13 at 13:28 ...
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How do I calculate the normal vector of a line segment?

Suppose I have a line segment going from (x1,y1) to (x2,y2). How do I calculate the normal vector perpendicular to the line? ...
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output

...e to go with @Moody_Mudskipper's answer: Using .drop=FALSE can give potentially unexpected results when one or more grouping variables are not coded as factors. See examples below: library(dplyr) data(iris) # Add an additional level to Species iris$Species = factor(iris$Species, levels=c(levels(ir...
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What happens when there's insufficient memory to throw an OutOfMemoryError?

... The JVM never really runs out of memory. It does memory computation of the heap stack in advance. The Structure of the JVM, Chapter 3, section 3.5.2 states: If Java virtual machine stacks can be dynamically expanded, and expansion is...
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Backbone.View “el” confusion

... A views el is where all the event binding takes place. You don't have to use it but if you want backbone to fire events you need to do your rendering work on the el. A views el is a DOM element but it does not have to be a pre-existing element. ...
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Compiling with g++ using multiple cores

Quick question: what is the compiler flag to allow g++ to spawn multiple instances of itself in order to compile large projects quicker (for example 4 source files at a time for a multi-core CPU)? ...
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How to iterate over rows in a DataFrame in Pandas

... From the documentation: "Iterating through pandas objects is generally slow. In many cases, iterating manually over the rows is not needed[...]". Your answer is correct (in the context of the question) but does not mention this anywhere, so it isn't a very good one. – ...
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Can you use @Autowired with static fields?

... In short, no. You cannot autowire or manually wire static fields in Spring. You'll have to write your own logic to do this. share | improve this answer | ...
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How can I find WPF controls by name or type?

...t while testing or using this algorithm to check your work. There is a small error in Tri Q's Algorithm. After the child is found, if childrenCount is > 1 and we iterate again we can overwrite the properly found child. Therefore I added a if (foundChild != null) break; into my code to deal with...