Does the np.nan in numpy array occupy memory?

Question

I have a huge file of csv which can not be loaded into memory. Transforming it to libsvm format may save some memory. There are many nan in csv file. If I read lines and store

Answer 1

As far as I know yes, nan and zero values occupy the same memory as any other value, however, you can address your problem in other ways:

Have you tried using a sparse vector? they are intended for vectors with a lot of 0 values and memory consumption is optimized

SVM Module Scipy

Sparse matrices Scipy

There you have some info about SVM and sparse matrices, if you have further questions just ask.

Edited to provide an answer as well as a solution