psignd={{-21.898772796666027`,-7.341584474440793`*^-23},{-21.740658913657608`,-1.2269407576223594`*^-22},{-21.58254503064919`,5.678583347789356`*^-24},{-21.42443114764077`,-3.278764030286238`*^-23},{-21.26631726463235`,-4.112645849739951`*^-22},{-21.10820338162393`,-2.9387392494401704`*^-22},{-20.95008949861551`,1.0561215360037718`*^-21},{-20.791975615607093`,3.777268280349187`*^-22},{-20.633861732598675`,1.228490430699356`*^-21},{-20.475747849590256`,-1.224667090945488`*^-21},{-20.317633966581838`,4.760656551046438`*^-21},{-20.15952008357342`,-3.934181870253858`*^-21},{-20.001406200565`,4.217994215630363`*^-21},{-19.84329231755658`,3.022896198847826`*^-22},{-19.68517843454816`,1.2752412823320146`*^-20},{-19.52706455153974`,5.819457257019687`*^-21},{-19.368950668531323`,1.797798958382353`*^-21},{-19.210836785522904`,2.6369865376403793`*^-21},{-19.052722902514486`,2.735269769430834`*^-21},{-18.894609019506067`,6.957557518984124`*^-20},{-18.736495136497645`,4.4186267112815385`*^-20},{-18.578381253489226`,4.4210140713860646`*^-20},{-18.420267370480808`,-2.4719758621334605`*^-20},{-18.26215348747239`,-8.590769804658484`*^-20},{-18.10403960446397`,-7.153752409754194`*^-20},{-17.945925721455552`,-5.58948698942255`*^-19},{-17.787811838447134`,-4.2999854219986196`*^-19},{-17.629697955438715`,-5.21232417425807`*^-19},{-17.471584072430296`,-3.158858273506674`*^-20},{-17.313470189421878`,-7.218734840936172`*^-19},{-17.155356306413456`,5.164842471750841`*^-20},{-16.997242423405037`,-3.5592230096746077`*^-19},{-16.83912854039662`,1.5840514473721326`*^-18},{-16.6810146573882`,1.3160488824268155`*^-19},{-16.52290077437978`,1.714524642243496`*^-18},{-16.364786891371363`,-6.520997335826716`*^-19},{-16.206673008362944`,1.3436075196698239`*^-18},{-16.048559125354522`,-5.7876842153765336`*^-18},{-15.890445242346106`,1.7573891048577954`*^-18},{-15.732331359337685`,-5.713110682158969`*^-18},{-15.574217476329267`,-5.470355984356455`*^-18},{-15.416103593320848`,-1.8199984867844636`*^-17},{-15.25798971031243`,-2.0825389811902427`*^-17},{-15.099875827304011`,-2.603652631549484`*^-17},{-14.941761944295592`,-8.5981517521289`*^-18},{-14.783648061287172`,-1.9055100707033778`*^-17},{-14.625534178278754`,1.3256089840091082`*^-17},{-14.467420295270335`,-1.0561233354848902`*^-17},{-14.309306412261915`,3.4859632204774734`*^-17},{-14.151192529253496`,-2.795298692408987`*^-17},{-13.993078646245078`,5.797579892788787`*^-17},{-13.834964763236659`,4.960045551106877`*^-18},{-13.67685088022824`,1.341527638606564`*^-16},{-13.51873699721982`,7.901016718464095`*^-17},{-13.360623114211402`,8.236053379997651`*^-17},{-13.202509231202983`,1.612557249189831`*^-16},{-13.044395348194564`,7.679304028450242`*^-17},{-12.886281465186144`,1.4874151017219224`*^-16},{-12.728167582177726`,4.1865651489848656`*^-17},{-12.570053699169307`,1.3575469702820406`*^-16},{-12.411939816160888`,-1.4676821962345878`*^-16},{-12.253825933152468`,-2.527347990769104`*^-16},{-12.09571205014405`,-2.5714803262251824`*^-16},{-11.937598167135631`,-3.518787118773515`*^-16},{-11.779484284127212`,-4.83676724678157`*^-16},{-11.621370401118794`,-7.557927035129141`*^-16},{-11.463256518110374`,-1.3591563086385859`*^-15},{-11.305142635101955`,-2.3975217570159163`*^-15},{-11.147028752093536`,-5.410780310632298`*^-15},{-10.988914869085118`,-1.0472619286202255`*^-14},{-10.830800986076698`,-2.259308100665181`*^-14},{-10.672687103068279`,-4.497204822988097`*^-14},{-10.51457322005986`,-9.15623620661128`*^-14},{-10.356459337051442`,-1.8445354449327337`*^-13},{-10.198345454043022`,-3.6852882447668283`*^-13},{-10.040231571034603`,-7.336366596557025`*^-13},{-9.882117688026185`,-1.4481822327190753`*^-12},{-9.724003805017766`,-2.8453050355638663`*^-12},{-9.565889922009346`,-5.5554555081890154`*^-12},{-9.407776039000927`,-1.0785471186921596`*^-11},{-9.249662155992509`,-2.0813495585220194`*^-11},{-9.09154827298409`,-3.992522426858813`*^-11},{-8.933434389975671`,-7.612194101614727`*^-11},{-8.775320506967251`,-1.4425010131349953`*^-10},{-8.617206623958833`,-2.7166798838985`*^-10},{-8.459092740950414`,-5.084533919010673`*^-10},{-8.300978857941995`,-9.45644535991053`*^-10},{-8.142864974933575`,-1.7476001551727647`*^-9},{-7.9847510919251565`,-3.208964443619711`*^-9},{-7.826637208916738`,-5.854207479512531`*^-9},{-7.668523325908319`,-1.0610152758401755`*^-8},{-7.510409442899899`,-1.9102700916464697`*^-8},{-7.3522955598914805`,-3.4162980016819196`*^-8},{-7.194181676883062`,-6.068364992002677`*^-8},{-7.036067793874643`,-1.0705541394344825`*^-7},{-6.877953910866225`,-1.8755619206152188`*^-7},{-6.7198400278578045`,-3.2628985968502975`*^-7},{-6.561726144849386`,-5.636212786310997`*^-7},{-6.403612261840967`,-9.665929682643258`*^-7},{-6.245498378832549`,-1.645627872634769`*^-6},{-6.0873844958241285`,-2.7810518784914986`*^-6},{-5.92927061281571`,-4.66478880788477`*^-6},{-5.771156729807291`,-7.765232845738199`*^-6},{-5.613042846798873`,-0.000012827108975504018`},{-5.454928963790454`,-0.000021023499117101644`},{-5.2968150807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here’s how to plot my wavefunction.  Use Show to combine this with the plot of your wavefunction.
The horizontal axis is x/b.

ListPlot[-psignd,Joined->True,PlotRange->{{-5,5},All}]