str(data_path)

proxtoolbox/experiments/ptychography/ptychographyExperiment.py

@@ -185,7 +185,7 @@ class PtychographyExperiment(Experiment):
                 print('* Save and unpack the Ptychography.tar.gz datafile in the               *')
                 print('*    ProxMatlab/InputData/Ptychography subdirectory                     *')
                 print('*************************************************************************')
-                errMsg = "File " + data_path + " was not found"
+                errMsg = "File " + str(data_path) + " was not found"
                 raise IOError(errMsg)
 
             mat_dict = loadMatFile(data_path)