Confused by syntax
how is:
different from this:
any comment?
wr=(wr=wtemp)*wpr-wi*wpi+wr;different from this:
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any comment?
In the first case you're reading from wr and writing to wr without synchronization. If wr is a scalar (for
example, a double or an int), the program has undefined behavior, anything can happen. If it's a class object, there are two equally correct possible outcomes.
Your second code sample is well-defined and thus can be reasoned about.
If you're not familiar with expression evaluation rules, check out http://en.cppreference.com/w/cpp/language/eval_order
example, a double or an int), the program has undefined behavior, anything can happen. If it's a class object, there are two equally correct possible outcomes.
Your second code sample is well-defined and thus can be reasoned about.
If you're not familiar with expression evaluation rules, check out http://en.cppreference.com/w/cpp/language/eval_order
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sorry...should have read:
how is that different than the 2 lines from above?
wr=(wtemp=wr)*wpr-wi*wpi+wrhow is that different than the 2 lines from above?
Last edited on
Those are the same for built-in operators (assuming temp is supposed to be wtemp). What caused the doubt?
I thought they were...not familiar with C++ so i wasn't sure if this did a different order of ops...
thanks for the feedback.
thanks for the feedback.
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