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Having a class members std::vector<double> v and int n, what is the difference between using the following on this vector, which is not initialized:
v.assign(n, 0.0); or
v.resize(n, 0.0); 
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C++ Vector Library - resize() FunctionThe C++ function std::vector::resize() changes the size of vector. If n is smaller than current size then extra elements are destroyed. If n is greater than current container size then new elements are inserted at the end of vector.
vector::resizeResizes the container to contain count elements. If the current size is greater than count , the container is reduced to its first count elements.
vector:: assign() is an STL in C++ which assigns new values to the vector elements by replacing old ones. It can also modify the size of the vector if necessary.
Calling resize() with a smaller size has no effect on the capacity of a vector . It will not free memory.
assign sets the size to n and all element values to 0.0, whereas resize sets the size to n and only new element values to 0.0.
If v is empty beforehand, they're the same, but assign is probably clearer.
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