diff --git a/mgatk/bin/python/variant_calling.py b/mgatk/bin/python/variant_calling.py
index c28385e..cdf3c84 100644
--- a/mgatk/bin/python/variant_calling.py
+++ b/mgatk/bin/python/variant_calling.py
@@ -156,7 +156,7 @@ def gather_possible_variants(base_coverage_dict, reference_file):
                           'n_cells_over_10', 'n_cells_over_20', 'n_cells_over_95',
                           'max_heteroplasmy', 'strand_correlation', 'mean_coverage']
 variant_output[['vmr', 'mean', 'variance', 'strand_correlation', 'mean_coverage', 'max_heteroplasmy']] = variant_output[['vmr', 'mean', 'variance', 'strand_correlation',
-                                                                                                                         'mean_coverage', 'max_heteroplasmy']].astype(np.float)
+                                                                                                                         'mean_coverage', 'max_heteroplasmy']].astype(float)
 
 # exclude variants with less than three cells
 multi_cell_variants = variant_output[variant_output['n_cells_conf_detected'] >= 3]['variant']
diff --git a/setup.py b/setup.py
index 1a0d308..0852b64 100644
--- a/setup.py
+++ b/setup.py
@@ -3,7 +3,7 @@
 """
 from setuptools import find_packages, setup
 
-dependencies = ['click', 'pysam', 'pytest', 'snakemake', 'biopython', 'numpy', 'pandas', 'optparse-pretty', 'regex', 'ruamel.yaml']
+dependencies = ['click', 'pysam', 'pytest', 'snakemake', 'biopython', 'numpy', 'pandas', 'optparse-pretty', 'regex', 'ruamel.yaml', 'matplotlib']
 
 setup(
     name='mgatk',