diff --git a/AmpScan/ssm.py b/AmpScan/ssm.py
index ed64f69c8dc8e931b334b2982e71cd680023e6c4..514b6b1075ef5f631eaa6a225be20a4e7e05498d 100644
--- a/AmpScan/ssm.py
+++ b/AmpScan/ssm.py
@@ -22,8 +22,8 @@ class pca(object):
     >>> import os
     >>> p = pca()
     >>> p.importFolder(os.getcwd()+"\\tests\\pca_tests")
-    >>> p.setBaseline(os.getcwd()+stl_file_3.stl)
-    >stl_file_3.stlcwd()+"\\tests\\pca_tests\\")
+    >>> p.setBaseline(os.getcwd()+"\\tests\\stl_file_3.stl")
+    >>> p.register(save=os.getcwd()+"\\tests\\pca_tests\\")
     >>> p.pca()
     >>> sfs = [1, 2]
     >>> newS = p.newShape(sfs)
@@ -132,11 +132,11 @@ class pca(object):
             to standard deviations about the mean
 
         """
-        if isinstance(sfs, (list, tuple, np.ndarray)):
+        if not isinstance(sfs, (list, tuple, np.ndarray)):
             raise TypeError('sfs is invalid type (expected array-like, found: {}'.format(type(sfs)))
-        if len(sfs) != len(self.pc_stdevs.shape):
+        if len(sfs) != len(self.pc_stdevs):
             raise ValueError('sfs must be of the same length as the number of '
-                             'principal components (expected {} but found {})'.format(self.pc_stdevs.shape, sfs.shape))
+                             'principal components (expected {} but found {})'.format(len(self.pc_stdevs), len(sfs)))
         if scale == 'eigs':
             sf = (self.pca_U * sfs).sum(axis=1)
         elif scale == 'std':
diff --git a/tests/__init__py.py b/tests/__init__py.py
index 97d12f026e5377bd47b031056e8ee2127f2aaa9b..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 100644
--- a/tests/__init__py.py
+++ b/tests/__init__py.py
@@ -1,2 +0,0 @@
-
-from tests.util import get_path
\ No newline at end of file
diff --git a/tests/pca_tests/sample_stl_sphere_BIN.stl b/tests/pca_tests/sample_stl_sphere_BIN.stl
deleted file mode 100644
index c9d4e3eeafa54a49e54f86b6b48e06bdcf77fec1..0000000000000000000000000000000000000000
--- a/tests/pca_tests/sample_stl_sphere_BIN.stl
+++ /dev/null
@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:23d4d80f3205706d0d53df58f592c99abcc0558a9c82cd59a89f43126b3e8313
-size 64084
diff --git a/tests/pca_tests/stl_file_3.stl b/tests/pca_tests/stl_file_3.stl
new file mode 100644
index 0000000000000000000000000000000000000000..c95508eaf21b1af7b779e72c26da6855d97ec416
--- /dev/null
+++ b/tests/pca_tests/stl_file_3.stl
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:b4d4d2f0165ec971f8311c9eaa03370b19c5f43a29490b9cf486ac2b6d7d0614
+size 64084