Error in the core plot configration
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I'm trying to use CorePlot for an ios application, i followed the instructions at: http://www.raywenderlich.com/13269/how-to-draw-graphs-with-core-plot-part-1
But even if the CorePlot-CocoaTouch.h file exists (CorePlot/CorePlotHeaders), the build failed  saying: 


/Users/zakariagaizi/Desktop/core_plot/core_plot/core_plot-Prefix.pch:14:36: error: CorePlot-CocoaTouch.h: No such file or directory


Any help please!!! Thank you very very much