Update Deprecated Pandas Function Call

Pandas.DataFrame.as_matrix is deprecated since version 0.23.0 (see docs
and PR 18458). According to the documentation for Pandas 0.25.1, the
recommended function is DataFrame.to_numpy() in place of DataFrame.values
or DataFrame.as_matrix().

pandas-dev/pandas#18458
https://pandas.pydata.org/pandas-docs/version/0.23/generated/pandas.DataFrame.as_matrix.html
https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.values.html

riskslim/helper_functions.py

@@ -212,7 +212,7 @@ def load_data_from_csv(dataset_csv_file, sample_weights_csv_file = None, fold_cs
     else:
         raise IOError('could not find dataset_csv_file: %s' % dataset_csv_file)
 
-    raw_data = df.as_matrix()
+    raw_data = df.to_numpy()
     data_headers = list(df.columns.values)
     N = raw_data.shape[0]
 
@@ -236,7 +236,7 @@ def load_data_from_csv(dataset_csv_file, sample_weights_csv_file = None, fold_cs
     else:
         if os.path.isfile(sample_weights_csv_file):
             sample_weights = pd.read_csv(sample_weights_csv_file, sep=',', header=None)
-            sample_weights = sample_weights.as_matrix()
+            sample_weights = sample_weights.to_numpy()
         else:
             raise IOError('could not find sample_weights_csv_file: %s' % sample_weights_csv_file)