DOC: add a nan masking example to the UnivariateSpline docstring
DOC: add a nan masking example to the UnivariateSpline docstring

example is by @juliantaylor,
https://github.com/scipy/scipy/issues/3531#issuecomment-40233093

dominicelse/scipy,trankmichael/scipy,trankmichael/scipy,pschella/scipy,chatcannon/scipy,mdhaber/scipy,vberaudi/scipy,fernand/scipy,apbard/scipy,njwilson23/scipy,njwilson23/scipy,bkendzior/scipy,larsmans/scipy,dominicelse/scipy,piyush0609/scipy,Kamp9/scipy,felipebetancur/scipy,ortylp/scipy,mdhaber/scipy,mortonjt/scipy,pizzathief/scipy,WillieMaddox/scipy,ilayn/scipy,fredrikw/scipy,gef756/scipy,ilayn/scipy,piyush0609/scipy,ndchorley/scipy,WillieMaddox/scipy,grlee77/scipy,arokem/scipy,mhogg/scipy,fredrikw/scipy,gef756/scipy,fernand/scipy,aman-iitj/scipy,jamestwebber/scipy,futurulus/scipy,aman-iitj/scipy,kalvdans/scipy,gertingold/scipy,anielsen001/scipy,petebachant/scipy,pnedunuri/scipy,pbrod/scipy,mortada/scipy,woodscn/scipy,ortylp/scipy,zxsted/scipy,felipebetancur/scipy,sauliusl/scipy,mdhaber/scipy,jakevdp/scipy,Shaswat27/scipy,cpaulik/scipy,witcxc/scipy,andyfaff/scipy,giorgiop/scipy,ales-erjavec/scipy,matthewalbani/scipy,pschella/scipy,richardotis/scipy,larsmans/scipy,vigna/scipy,jor-/scipy,felipebetancur/scipy,larsmans/scipy,haudren/scipy,matthewalbani/scipy,ales-erjavec/scipy,grlee77/scipy,sonnyhu/scipy,aeklant/scipy,vanpact/scipy,lhilt/scipy,ndchorley/scipy,woodscn/scipy,zaxliu/scipy,newemailjdm/scipy,felipebetancur/scipy,mhogg/scipy,anielsen001/scipy,nmayorov/scipy,sauliusl/scipy,kleskjr/scipy,WarrenWeckesser/scipy,jamestwebber/scipy,jsilter/scipy,cpaulik/scipy,ChanderG/scipy,vanpact/scipy,haudren/scipy,piyush0609/scipy,cpaulik/scipy,pizzathief/scipy,mingwpy/scipy,zaxliu/scipy,Kamp9/scipy,ortylp/scipy,giorgiop/scipy,rgommers/scipy,aeklant/scipy,anntzer/scipy,petebachant/scipy,futurulus/scipy,kleskjr/scipy,jjhelmus/scipy,ilayn/scipy,anielsen001/scipy,vigna/scipy,andim/scipy,sriki18/scipy,larsmans/scipy,zxsted/scipy,efiring/scipy,petebachant/scipy,mdhaber/scipy,Newman101/scipy,larsmans/scipy,vhaasteren/scipy,Dapid/scipy,vhaasteren/scipy,ales-erjavec/scipy,e-q/scipy,aeklant/scipy,mingwpy/scipy,perimosocordiae/scipy,aarchiba/scipy,ChanderG/scipy,chatcannon/scipy,jakevdp/scipy,matthew-brett/scipy,zerothi/scipy,Gillu13/scipy,Dapid/scipy,perimosocordiae/scipy,argriffing/scipy,Kamp9/scipy,nonhermitian/scipy,Eric89GXL/scipy,mortada/scipy,endolith/scipy,piyush0609/scipy,mtrbean/scipy,nvoron23/scipy,fernand/scipy,vanpact/scipy,mdhaber/scipy,fredrikw/scipy,nmayorov/scipy,mtrbean/scipy,mgaitan/scipy,jonycgn/scipy,maniteja123/scipy,jonycgn/scipy,perimosocordiae/scipy,pizzathief/scipy,richardotis/scipy,sauliusl/scipy,kalvdans/scipy,sriki18/scipy,jamestwebber/scipy,dominicelse/scipy,rmcgibbo/scipy,woodscn/scipy,behzadnouri/scipy,hainm/scipy,mingwpy/scipy,jjhelmus/scipy,newemailjdm/scipy,hainm/scipy,lhilt/scipy,mortonjt/scipy,mtrbean/scipy,anielsen001/scipy,Dapid/scipy,tylerjereddy/scipy,bkendzior/scipy,giorgiop/scipy,scipy/scipy,pbrod/scipy,kalvdans/scipy,zerothi/scipy,andyfaff/scipy,aeklant/scipy,befelix/scipy,hainm/scipy,zaxliu/scipy,ortylp/scipy,WillieMaddox/scipy,jakevdp/scipy,apbard/scipy,mortonjt/scipy,rmcgibbo/scipy,newemailjdm/scipy,befelix/scipy,vanpact/scipy,mgaitan/scipy,befelix/scipy,bkendzior/scipy,Eric89GXL/scipy,jseabold/scipy,argriffing/scipy,maniteja123/scipy,vberaudi/scipy,efiring/scipy,Srisai85/scipy,anielsen001/scipy,ortylp/scipy,nvoron23/scipy,matthew-brett/scipy,endolith/scipy,arokem/scipy,raoulbq/scipy,ortylp/scipy,pizzathief/scipy,jor-/scipy,Shaswat27/scipy,FRidh/scipy,mgaitan/scipy,petebachant/scipy,jakevdp/scipy,futurulus/scipy,niknow/scipy,argriffing/scipy,aarchiba/scipy,sauliusl/scipy,mikebenfield/scipy,zaxliu/scipy,lukauskas/scipy,njwilson23/scipy,pschella/scipy,josephcslater/scipy,sauliusl/scipy,ndchorley/scipy,mikebenfield/scipy,lukauskas/scipy,hainm/scipy,minhlongdo/scipy,jor-/scipy,Newman101/scipy,gdooper/scipy,maciejkula/scipy,andim/scipy,witcxc/scipy,Newman101/scipy,vigna/scipy,mortada/scipy,behzadnouri/scipy,WarrenWeckesser/scipy,gfyoung/scipy,Gillu13/scipy,anntzer/scipy,kleskjr/scipy,jseabold/scipy,Stefan-Endres/scipy,efiring/scipy,Srisai85/scipy,nmayorov/scipy,aman-iitj/scipy,hainm/scipy,gef756/scipy,mgaitan/scipy,minhlongdo/scipy,nvoron23/scipy,pschella/scipy,josephcslater/scipy,zaxliu/scipy,e-q/scipy,mgaitan/scipy,vberaudi/scipy,maniteja123/scipy,niknow/scipy,zxsted/scipy,gertingold/scipy,raoulbq/scipy,Srisai85/scipy,jor-/scipy,raoulbq/scipy,tylerjereddy/scipy,Newman101/scipy,rmcgibbo/scipy,jonycgn/scipy,hainm/scipy,sriki18/scipy,FRidh/scipy,mhogg/scipy,pizzathief/scipy,scipy/scipy,Shaswat27/scipy,sonnyhu/scipy,mikebenfield/scipy,kleskjr/scipy,haudren/scipy,cpaulik/scipy,andyfaff/scipy,pyramania/scipy,WillieMaddox/scipy,mhogg/scipy,WarrenWeckesser/scipy,anntzer/scipy,ales-erjavec/scipy,scipy/scipy,dominicelse/scipy,raoulbq/scipy,zxsted/scipy,matthew-brett/scipy,nmayorov/scipy,argriffing/scipy,maciejkula/scipy,gfyoung/scipy,Newman101/scipy,raoulbq/scipy,josephcslater/scipy,zxsted/scipy,minhlongdo/scipy,richardotis/scipy,futurulus/scipy,scipy/scipy,tylerjereddy/scipy,mortada/scipy,maniteja123/scipy,ChanderG/scipy,zerothi/scipy,jonycgn/scipy,behzadnouri/scipy,gertingold/scipy,Gillu13/scipy,witcxc/scipy,lhilt/scipy,lhilt/scipy,mtrbean/scipy,Stefan-Endres/scipy,Shaswat27/scipy,lukauskas/scipy,newemailjdm/scipy,jjhelmus/scipy,maciejkula/scipy,bkendzior/scipy,anntzer/scipy,maciejkula/scipy,nmayorov/scipy,gertingold/scipy,mikebenfield/scipy,pnedunuri/scipy,befelix/scipy,felipebetancur/scipy,jjhelmus/scipy,endolith/scipy,efiring/scipy,behzadnouri/scipy,Dapid/scipy,surhudm/scipy,tylerjereddy/scipy,dominicelse/scipy,apbard/scipy,endolith/scipy,Gillu13/scipy,person142/scipy,arokem/scipy,sriki18/scipy,jseabold/scipy,lukauskas/scipy,jseabold/scipy,fernand/scipy,endolith/scipy,niknow/scipy,ales-erjavec/scipy,mingwpy/scipy,pschella/scipy,person142/scipy,ndchorley/scipy,argriffing/scipy,person142/scipy,arokem/scipy,surhudm/scipy,Kamp9/scipy,niknow/scipy,person142/scipy,vhaasteren/scipy,andyfaff/scipy,e-q/scipy,Kamp9/scipy,vhaasteren/scipy,trankmichael/scipy,gfyoung/scipy,kleskjr/scipy,zerothi/scipy,kalvdans/scipy,chatcannon/scipy,jor-/scipy,grlee77/scipy,kalvdans/scipy,ilayn/scipy,giorgiop/scipy,minhlongdo/scipy,mortonjt/scipy,ChanderG/scipy,dch312/scipy,nonhermitian/scipy,mhogg/scipy,vberaudi/scipy,pyramania/scipy,grlee77/scipy,trankmichael/scipy,Eric89GXL/scipy,pnedunuri/scipy,maniteja123/scipy,vanpact/scipy,behzadnouri/scipy,anntzer/scipy,Gillu13/scipy,scipy/scipy,ndchorley/scipy,WarrenWeckesser/scipy,perimosocordiae/scipy,vhaasteren/scipy,Newman101/scipy,minhlongdo/scipy,surhudm/scipy,aman-iitj/scipy,apbard/scipy,jsilter/scipy,giorgiop/scipy,WarrenWeckesser/scipy,niknow/scipy,giorgiop/scipy,surhudm/scipy,zxsted/scipy,felipebetancur/scipy,anielsen001/scipy,WillieMaddox/scipy,behzadnouri/scipy,Srisai85/scipy,jamestwebber/scipy,dch312/scipy,andyfaff/scipy,mingwpy/scipy,fernand/scipy,ilayn/scipy,trankmichael/scipy,befelix/scipy,efiring/scipy,FRidh/scipy,jonycgn/scipy,mortada/scipy,nonhermitian/scipy,lukauskas/scipy,Srisai85/scipy,chatcannon/scipy,Kamp9/scipy,aarchiba/scipy,andim/scipy,aman-iitj/scipy,newemailjdm/scipy,sauliusl/scipy,Stefan-Endres/scipy,ilayn/scipy,chatcannon/scipy,gfyoung/scipy,gfyoung/scipy,aarchiba/scipy,matthewalbani/scipy,e-q/scipy,Stefan-Endres/scipy,nvoron23/scipy,maciejkula/scipy,andim/scipy,haudren/scipy,nvoron23/scipy,anntzer/scipy,jsilter/scipy,pbrod/scipy,Srisai85/scipy,surhudm/scipy,gdooper/scipy,scipy/scipy,petebachant/scipy,jseabold/scipy,piyush0609/scipy,mikebenfield/scipy,rmcgibbo/scipy,sonnyhu/scipy,ChanderG/scipy,pnedunuri/scipy,ndchorley/scipy,matthew-brett/scipy,woodscn/scipy,witcxc/scipy,pyramania/scipy,pbrod/scipy,woodscn/scipy,maniteja123/scipy,gertingold/scipy,fredrikw/scipy,kleskjr/scipy,newemailjdm/scipy,vigna/scipy,sriki18/scipy,Gillu13/scipy,woodscn/scipy,Eric89GXL/scipy,mdhaber/scipy,pbrod/scipy,dch312/scipy,WarrenWeckesser/scipy,Dapid/scipy,jseabold/scipy,rgommers/scipy,arokem/scipy,Shaswat27/scipy,trankmichael/scipy,mingwpy/scipy,chatcannon/scipy,Stefan-Endres/scipy,pyramania/scipy,rmcgibbo/scipy,matthewalbani/scipy,Stefan-Endres/scipy,raoulbq/scipy,pnedunuri/scipy,jakevdp/scipy,Dapid/scipy,mortada/scipy,rgommers/scipy,Eric89GXL/scipy,minhlongdo/scipy,pnedunuri/scipy,rmcgibbo/scipy,matthew-brett/scipy,jjhelmus/scipy,sonnyhu/scipy,petebachant/scipy,pbrod/scipy,andyfaff/scipy,witcxc/scipy,person142/scipy,mortonjt/scipy,jsilter/scipy,nonhermitian/scipy,Eric89GXL/scipy,cpaulik/scipy,josephcslater/scipy,zerothi/scipy,apbard/scipy,vberaudi/scipy,njwilson23/scipy,ChanderG/scipy,ales-erjavec/scipy,rgommers/scipy,mortonjt/scipy,Shaswat27/scipy,grlee77/scipy,andim/scipy,gef756/scipy,perimosocordiae/scipy,zaxliu/scipy,haudren/scipy,andim/scipy,futurulus/scipy,aman-iitj/scipy,FRidh/scipy,tylerjereddy/scipy,gdooper/scipy,njwilson23/scipy,gdooper/scipy,argriffing/scipy,gdooper/scipy,mhogg/scipy,mtrbean/scipy,sonnyhu/scipy,jsilter/scipy,lhilt/scipy,richardotis/scipy,gef756/scipy,richardotis/scipy,richardotis/scipy,dch312/scipy,larsmans/scipy,vhaasteren/scipy,nvoron23/scipy,surhudm/scipy,FRidh/scipy,sonnyhu/scipy,jonycgn/scipy,aarchiba/scipy,mgaitan/scipy,efiring/scipy,mtrbean/scipy,gef756/scipy,aeklant/scipy,FRidh/scipy,njwilson23/scipy,endolith/scipy,rgommers/scipy,bkendzior/scipy,fredrikw/scipy,fernand/scipy,WillieMaddox/scipy,piyush0609/scipy,zerothi/scipy,vigna/scipy,vberaudi/scipy,dch312/scipy,cpaulik/scipy,jamestwebber/scipy,perimosocordiae/scipy,niknow/scipy,haudren/scipy,josephcslater/scipy,vanpact/scipy,sriki18/scipy,matthewalbani/scipy,pyramania/scipy,fredrikw/scipy,lukauskas/scipy,futurulus/scipy,e-q/scipy,nonhermitian/scipy