From 9e199e4820a82fb23786ce335cfedda86271be53 Mon Sep 17 00:00:00 2001
From: Leland McInnes <leland.mcinnes@gmail.com>
Date: Wed, 23 May 2018 19:54:21 -0400
Subject: [PATCH] Fix for issue #71 -- sparse correlation not available in
 pairwise_distances

---
 umap/umap_.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/umap/umap_.py b/umap/umap_.py
index ecee1fe5..b01e4f35 100644
--- a/umap/umap_.py
+++ b/umap/umap_.py
@@ -1408,7 +1408,7 @@ def fit(self, X, y=None):
             print("Construct fuzzy simplicial set")
 
         # Handle small cases efficiently by computing all distances
-        if X.shape[0] < 4096:
+        if X.shape[0] < 4096 and not (metric == 'correlation' and scipy.sparse.isspmatrix_csr(X)):
             dmat = pairwise_distances(X, metric=self.metric, **self.metric_kwds)
             self.graph = fuzzy_simplicial_set(
                 dmat,