From 965f37b7847855febea946d645018f8bc0783ca4 Mon Sep 17 00:00:00 2001
From: "Vandenplas, Jeremie" <jeremie.vandenplas@gmail.com>
Date: Sun, 19 Jan 2020 11:35:11 +0100
Subject: [PATCH] moved to submodules

how to use pure functions in submodules
---
 src/CMakeLists.txt                    |  1 +
 src/stdlib_experimental_stat.f90      | 47 +++++----------------------
 src/stdlib_experimental_stat_mean.f90 | 39 ++++++++++++++++++++++
 3 files changed, 49 insertions(+), 38 deletions(-)
 create mode 100644 src/stdlib_experimental_stat_mean.f90

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index db10a2366..e27ab54d0 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -5,6 +5,7 @@ set(SRC
     stdlib_experimental_kinds.f90
     stdlib_experimental_optval.f90
     stdlib_experimental_system.F90
+    stdlib_experimental_stat_mean.f90
     stdlib_experimental_stat.f90
 )
 
diff --git a/src/stdlib_experimental_stat.f90 b/src/stdlib_experimental_stat.f90
index 45f2c9aba..756b3b43b 100644
--- a/src/stdlib_experimental_stat.f90
+++ b/src/stdlib_experimental_stat.f90
@@ -1,7 +1,5 @@
 module stdlib_experimental_stat
 use stdlib_experimental_kinds, only: sp, dp, qp
-use stdlib_experimental_error, only: error_stop
-use stdlib_experimental_optval, only: optval
 implicit none
 private
 ! Public API
@@ -9,42 +7,15 @@ module stdlib_experimental_stat
 
 
 interface mean
-    module procedure mean_1_dp_dp
-    module procedure mean_2_dp_dp
+    module function mean_1_dp_dp(mat) result(res)
+        real(dp), intent(in) :: mat(:)
+        real(dp) ::res
+    end function
+    module function mean_2_dp_dp(mat, dim) result(res)
+        real(dp), intent(in) :: mat(:,:)
+        integer, intent(in), optional :: dim
+        real(dp), allocatable ::res(:)
+    end function
 end interface
 
-contains
-
-pure function mean_1_dp_dp(mat) result(res)
-    real(dp), intent(in) :: mat(:)
-    real(dp) ::res
-
-    res = sum(mat) / real(size(mat), dp)
-
-end function mean_1_dp_dp
-
-function mean_2_dp_dp(mat, dim) result(res)
-    real(dp), intent(in) :: mat(:,:)
-    integer, intent(in), optional :: dim
-    real(dp), allocatable ::res(:)
-
-    integer :: i
-    integer :: dim_
-
-    dim_ = optval(dim, 1)
-
-    allocate(res(size(mat, dim_)))
-
-    if (dim_ == 1) then
-        do i=1, size(mat, dim_)
-            res(i) = mean_1_dp_dp(mat(i,:))
-        end do
-    else if (dim_ == 2) then
-        do i=1, size(mat, dim_)
-            res(i) = mean_1_dp_dp(mat(:,i))
-        end do
-    end if
-
-end function mean_2_dp_dp
-
 end module
diff --git a/src/stdlib_experimental_stat_mean.f90 b/src/stdlib_experimental_stat_mean.f90
new file mode 100644
index 000000000..97cd62186
--- /dev/null
+++ b/src/stdlib_experimental_stat_mean.f90
@@ -0,0 +1,39 @@
+submodule (stdlib_experimental_stat) stdlib_experimental_stat_mean
+use stdlib_experimental_optval, only: optval
+implicit none
+
+contains
+
+module function mean_1_dp_dp(mat) result(res)
+    real(dp), intent(in) :: mat(:)
+    real(dp) ::res
+
+    res = sum(mat) / real(size(mat), dp)
+
+end function mean_1_dp_dp
+
+module function mean_2_dp_dp(mat, dim) result(res)
+    real(dp), intent(in) :: mat(:,:)
+    integer, intent(in), optional :: dim
+    real(dp), allocatable ::res(:)
+
+    integer :: i
+    integer :: dim_
+
+    dim_ = optval(dim, 1)
+
+    allocate(res(size(mat, dim_)))
+
+    if (dim_ == 1) then
+        do i=1, size(mat, dim_)
+            res(i) = mean_1_dp_dp(mat(i,:))
+        end do
+    else if (dim_ == 2) then
+        do i=1, size(mat, dim_)
+            res(i) = mean_1_dp_dp(mat(:,i))
+        end do
+    end if
+
+end function mean_2_dp_dp
+
+end submodule