fftw_fix (gwastro#4418)

* Allow pycbc inspiral to run with only numpy fft

* Remove Unneeded function from npfft.py

---------

Co-authored-by: Neeresh Kumar Perla <neereshkumarperla@Neereshs-MacBook-Pro.local>

bin/pycbc_inspiral

@@ -301,19 +301,21 @@ def template_triggers(t_num):
     return out_vals_all, tparam
 
 with ctx:
-    # The following FFTW specific options needed to wait until
-    # we were inside the scheme context.
+    if opt.fft_backends == 'fftw':
 
-    # Import system wisdom.
-    if opt.fftw_import_system_wisdom:
-        fft.fftw.import_sys_wisdom()
+        # The following FFTW specific options needed to wait until
+        # we were inside the scheme context.
 
-    # Read specified user-provided wisdom files
-    if opt.fftw_input_float_wisdom_file is not None:
-        fft.fftw.import_single_wisdom_from_filename(opt.fftw_input_float_wisdom_file)
+        # Import system wisdom.
+        if opt.fftw_import_system_wisdom:
+            fft.fftw.import_sys_wisdom()
 
-    if opt.fftw_input_double_wisdom_file is not None:
-        fft.fftw.import_double_wisdom_from_filename(opt.fftw_input_double_wisdom_file)
+        # Read specified user-provided wisdom files
+        if opt.fftw_input_float_wisdom_file is not None:
+            fft.fftw.import_single_wisdom_from_filename(opt.fftw_input_float_wisdom_file)
+
+        if opt.fftw_input_double_wisdom_file is not None:
+            fft.fftw.import_double_wisdom_from_filename(opt.fftw_input_double_wisdom_file)
 
     flow = opt.low_frequency_cutoff
     flen = strain_segments.freq_len
@@ -499,10 +501,11 @@ event_mgr.save_performance(ncores, len(segments), len(bank), run_time, tsetup)
 logging.info("Writing out triggers")
 event_mgr.write_events(opt.output)
 
-if opt.fftw_output_float_wisdom_file:
-    fft.fftw.export_single_wisdom_to_filename(opt.fftw_output_float_wisdom_file)
+if opt.fft_backends == 'fftw':
+    if opt.fftw_output_float_wisdom_file:
+        fft.fftw.export_single_wisdom_to_filename(opt.fftw_output_float_wisdom_file)
 
-if opt.fftw_output_double_wisdom_file:
-    fft.fftw.export_double_wisdom_to_filename(opt.fftw_output_double_wisdom_file)
+    if opt.fftw_output_double_wisdom_file:
+        fft.fftw.export_double_wisdom_to_filename(opt.fftw_output_double_wisdom_file)
 
 logging.info("Finished")