How to plot smooth sine wave curves?

I want to plot the graph in the attached image in the positive direction, but I don't know how because clearly it isn't a sine wave. At least for one curve not necessary all curves( blue and red).

[darova]

How do you know if its not a sine? Do you have some attempts?

[Amir Tawfik]

Because the sine wave doesn't have a smooth start, in other words just plot a sine wave and zoom in a its start u will find it looks like a ramp. Anyway my target is to plot it but in the positive direction and I can't make a code that plots at least the blue curve.

[Image Analyst]

The jaggies look like an opengl problem. What does this show:

>> opengl info

[Amir Tawfik]

Does this relate to the question?

[darova]

Can't you plot sin() and add to data straight line?

[John D'Errico]

@Darova - there was no need to flag image analyst's question. In fact, it very well might be something of significance. Even if in fact, his question turns out to be not pertinent, please don't flag someone for constructively attempting to make a positive contribution to a discussion. That is inappropriate.

In order to resolve anything here, I would need to know the actual data that went into creating the plot, and how was the data created. That is, do we in fact know the data is truly a sine wave? Or is it really just a vaguely sinusoidal curve?

[Amir Tawfik]

Thats what I am exactly missing, source did't mention the base function of this wave or is just a tabular data.? Realy I don't know.