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Specify Location and Length of Streamlines
Use detailed controls for location, style and length of streamlines.
In[1]:=

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StreamPlot[{y, (1 - x^2) x}, {x, -1.5, 1.5}, {y, -1.5, 1.5}, 

 StreamPoints -> {{{-0.12, 0.1196} -> 

     Directive[Thickness[Large], Red], 8}, Automatic, Scaled[2.5]}, 

 StreamScale -> None]
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