need interpolation algorithm... not cosine

BlitzMax Forums/BlitzMax Programming/need interpolation algorithm... not cosine

anybody have any ideas for a quick interpolation algorithm that would look something like this... as opposed to the second cosine graph?

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             00000000000000000000000000000000000000
             
             
             
             
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           0                                             0
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                           0000       0000
                               0000000


thanks!