validity of testing method

[esraa-saleh]

Hello,
In the case of the sine wave, we are sampling the wave at equal "time" or x intervals. However, since its periodic, wouldn't that mean that test data is essentially a copy of the training data ? Would that be a valid method of testing though ?

Thanks !

[singh-hrituraj]

It has higher probability of being very similar to the training data but it will not be the same because of the fact that sine wave in its entire cycle can have theoretically infinitely many values. Even though it is periodic, the test values have been taken from the different points of the period of wave.

Obviously, it will not have very large differences from the training dataset due to its periodic nature but there is no alternative way to test the prediction of a sine wave. I

[esraa-saleh]

Ah, I see. Thank you for your answer.