constant

SparseArray/__init__.py

@@ -14,4 +14,4 @@
 
 from .sparse_array import SparseArray
 __all__ = ["SparseArray"]
-__version__ = '0.8.12'
+__version__ = '0.8.13'

SparseArray/sparse_array.pyx

@@ -65,6 +65,21 @@ cdef class SparseArray:
         r.data = array.array('d', [x[1] for x in index_data])
         r.non_zero = len(index_data)
         return r
+
+    @classmethod
+    def constant(cls, value, index, size):
+        cdef SparseArray r = cls()
+        cdef double *data_value 
+        cdef Py_ssize_t i, index_size = len(index)
+        r._len = size
+        r.non_zero = index_size
+        r.index = array.array('I', index)
+        r.data = array.clone(r.data, index_size, zero=False)
+        data_value = r.data.data.as_doubles
+        for i in range(index_size):
+            data_value[i] = value
+        return r
+
 
     @property
     def density(self):

SparseArray/tests/test_sparse_array.py

@@ -610,4 +610,14 @@ def test_argmin():
     sp_res = SparseArray.argmin([a, b, c])
     [assert_almost_equals(x, y) for x, y in zip(res, sp_res.full_array())]
 
-
+
+def test_constant():
+    index = [x for x in range(0, 100, 10)]
+    a = SparseArray.constant(-2.3, index, 100)
+    for v, w in zip(a.index, index):
+        assert_almost_equals(v, w)
+    for v in a.data:
+        assert_almost_equals(v, -2.3)
+    assert len(a) == 100
+    assert a.non_zero == 10
+

VERSION

@@ -1 +1 @@
-0.8.12
+0.8.13