diff --git a/Cargo.lock b/Cargo.lock
index e40cbf5..f123260 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -62,7 +62,7 @@ dependencies = [
 name = "konnoohmachi"
 version = "1.0.0"
 dependencies = [
- "ndarray",
+ "ndarray 0.16.0",
  "numpy",
  "pyo3",
 ]
@@ -94,9 +94,9 @@ dependencies = [
 
 [[package]]
 name = "ndarray"
-version = "0.15.4"
+version = "0.15.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dec23e6762830658d2b3d385a75aa212af2f67a4586d4442907144f3bb6a1ca8"
+checksum = "adb12d4e967ec485a5f71c6311fe28158e9d6f4bc4a447b474184d0f91a8fa32"
 dependencies = [
  "matrixmultiply",
  "num-complex",
@@ -105,6 +105,21 @@ dependencies = [
  "rawpointer",
 ]
 
+[[package]]
+name = "ndarray"
+version = "0.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "087ee1ca8a7c22830c2bba4a96ed8e72ce0968ae944349324d52522f66aa3944"
+dependencies = [
+ "matrixmultiply",
+ "num-complex",
+ "num-integer",
+ "num-traits",
+ "portable-atomic",
+ "portable-atomic-util",
+ "rawpointer",
+]
+
 [[package]]
 name = "num-complex"
 version = "0.4.1"
@@ -141,7 +156,7 @@ checksum = "7f3a190dd1aa88ee0de91e59e970d5b85cfa079a9ff6531b69f811ccd0c2a6e1"
 dependencies = [
  "cfg-if 0.1.10",
  "libc",
- "ndarray",
+ "ndarray 0.15.6",
  "num-complex",
  "num-traits",
  "pyo3",
@@ -197,6 +212,21 @@ dependencies = [
  "proc-macro-hack",
 ]
 
+[[package]]
+name = "portable-atomic"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da544ee218f0d287a911e9c99a39a8c9bc8fcad3cb8db5959940044ecfc67265"
+
+[[package]]
+name = "portable-atomic-util"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fcdd8420072e66d54a407b3316991fe946ce3ab1083a7f575b2463866624704d"
+dependencies = [
+ "portable-atomic",
+]
+
 [[package]]
 name = "proc-macro-hack"
 version = "0.5.19"
diff --git a/Cargo.toml b/Cargo.toml
index 37192c2..2704361 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,7 +10,7 @@ description = "Efficient spectral smoothing"
 crate-type = ["cdylib"]
 
 [dependencies]
-ndarray = {version="0.15.4"}
+ndarray = {version="0.16.0"}
 numpy = "0.15"
 
 [dependencies.pyo3]