Merge pull request #1 from zoziha/function/diff

Add `diff` function

doc/specs/forlab_linalg.md

@@ -0,0 +1,62 @@
+---
+title: LINALG
+---
+
+# LINALG
+
+[TOC]
+
+## `diff` - diff computes differences of arrays.
+
+### Status
+
+Experimental
+
+### Description
+y = diff(x) returns differences between adjacent elements of vector x.  
+y = diff(x, n) returns the nth difference by applying the diff(x) operator recursively n times.  
+B = diff(A) returns differences between adjacent elements of array A along the first dimension.  
+B = diff(A, n) returns the nth difference by applying the diff(A) operator recursively n times.  
+B = diff(A, dim) returns differences between adjacent elements of array A along the dimension given by dim.  
+B = diff(A, n, dim) returns the nth difference along the dimension given by dim by applying the diff(A, dim) operator recursively n times.
+
+
+### Syntax
+
+For vector:  
+`result = [[forlab_linalg(module):diff(interface)]](x [, n])`
+
+For matrix:  
+`result = [[forlab_linalg(module):diff(interface)]](A [, n, dim])`
+
+### Arguments
+
+`x`: Shall be a `real` type of verctor.
+`A`: Shall be a `real` type of matrix.
+
+`n` (optional): Shall be a `integer` type.
+`dim` (optional): Shall be a `integer` type.
+
+
+### Return value
+
+Return differences between adjacent elements of vector `x` or matrix `A`.
+
+### Example
+
+```fortran
+program test_linalg_diff
+    use forlab_linalg, only: diff
+    use forlab_linalg, only: linspace
+    use forlab_io, only: disp
+    implicit none
+
+    real :: x(10)
+    
+    call linspace(x, 0.0, 9.0)
+    call disp(x, "Linspace(x) : ")
+    call disp(diff(x), "Test_linalg_diff : ")
+    
+    
+end program test_linalg_diff
+```

doc/specs/forlab_math.md

@@ -0,0 +1,11 @@
+---
+title: MATH
+---
+
+# MATH
+
+[TOC]
+
+## `randu`
+
+## `randn`

doc/specs/index.md

@@ -13,15 +13,12 @@ This is and index/directory of the specifications (specs) for each new module/fe
 
  - [IO](./forlab_io.html) - Input/output helper & convenience
  - [math](./forlab_math.html) - Math functions
- - [linalg](./stdlib_linalg.html) - Linear Algebra
- - [logger](./stdlib_logger.html) - Runtime logging system
- - [optval](./stdlib_optval.html) - Fallback value for optional arguments
- - [quadrature](./stdlib_quadrature.html) - Numerical integration
- - [sorting](./stdlib_sorting.html) - Sorting of rank one arrays
- - [stats](./stdlib_stats.html) - Descriptive Statistics
- - [stats_distribution_PRNG](./stdlib_stats_distribution_PRNG.html) - Probability Distributions random number generator
- - [string\_type](./stdlib_string_type.html) - Basic string support
- - [strings](./stdlib_strings.html) - String handling and manipulation routines
+ - [linalg](./forlab_linalg.html) - Linear Algebra
+ - [logger](./forlab_logger.html) - Runtime logging system
+ - [quadrature](./forlab_quadrature.html) - Numerical integration
+ - [sorting](./forlab_sorting.html) - Sorting of rank one arrays
+ - [stats](./forlab_stats.html) - Descriptive Statistics
+ - [strings](./forlab_strings.html) - String handling and manipulation routines
 
 ## Released/Stable Features & Modules
 

fpm.toml

@@ -26,73 +26,77 @@ source-dir="src"
 ## [io] tests
 [[test]]
 name = "io_bin"
-source-dir = "tests/io"
+source-dir = "test/io"
 main = "test_io_bin.f90"
 [[test]]
 name = "io_disp"
-source-dir = "tests/io"
+source-dir = "test/io"
 main = "test_io_disp.f90"
 [[test]]
 name = "io_file"
-source-dir = "tests/io"
+source-dir = "test/io"
 main = "test_io_file.f90"
 [[test]]
 name = "io_set_color"
-source-dir = "tests/io"
+source-dir = "test/io"
 main = "test_io_set_color.f90"
 
 ## [linalg] tests
 [[test]]
+name = "linalg_diff"
+source-dir = "test/linalg"
+main = "test_linalg_diff.f90"
+[[test]]
 name = "linalg_i"
-source-dir = "tests/linalg"
+source-dir = "test/linalg"
 main = "test_linalg_i.f90"
 [[test]]
 name = "linalg_linspace"
-source-dir = "tests/linalg"
+source-dir = "test/linalg"
 main = "test_linalg_linspace.f90"
 [[test]]
 name = "linalg_tri"
-source-dir = "tests/linalg"
+source-dir = "test/linalg"
 main = "test_linalg_tri.f90"
 [[test]]
 name = "linalg_x"
-source-dir = "tests/linalg"
+source-dir = "test/linalg"
 main = "test_linalg_x.f90"
 
 ## [math] tests
 [[test]]
 name = "math_angle"
-source-dir = "tests/math"
+source-dir = "test/math"
 main = "test_math_angle.f90"
 [[test]]
 name = "math_degcir"
-source-dir = "tests/math"
+source-dir = "test/math"
 main = "test_math_degcir.f90"
 
 ## [stats] tests
 [[test]]
 name = "stats_rand"
-source-dir = "tests/stats"
+source-dir = "test/stats"
 main = "test_stats_rand.f90"
 [[test]]
 name = "stats_var"
-source-dir = "tests/stats"
+source-dir = "test/stats"
 main = "test_stats_var.f90"
 
 ## [strings] tests
 [[test]]
 name = "strings_format_string"
-source-dir = "tests/strings"
+source-dir = "test/strings"
 main = "test_strings_format_string.f90"
 
 ## [sorting] tests
 [[test]]
 name = "sorting_sort"
-source-dir = "tests/sorting"
+source-dir = "test/sorting"
 main = "test_sorting_sort.f90"
 
 ## [time] tests
 [[test]]
 name = "time_tioc"
-source-dir = "tests/time"
+source-dir = "test/time"
 main = "test_time_tioc.f90"

meta-src/forlab_.f95

@@ -2154,76 +2154,9 @@ subroutine deg2utm1(lat, lon, east, north, zn, zl)
         return
     end subroutine deg2utm1
 
-    ! diff
-    !-----------------------------------------------------------------------
-    ! diff computes differences of arrays
-    !
-    ! Syntax
-    !-----------------------------------------------------------------------
-    ! y = diff(x)
-    ! y = diff(x, n)
-    ! B = diff(A)
-    ! B = diff(A, n)
-    ! B = diff(A, dim)
-    ! B = diff(A, n, dim)
-    !
-    ! Description
-    !-----------------------------------------------------------------------
-    ! y = diff(x) returns differences between adjacent elements of vector x.
-    !
-    ! y = diff(x, n) returns the nth difference by applying the diff(x)
-    ! operator recursively n times.
-    !
-    ! B = diff(A) returns differences between adjacent elements of array A
-    ! along the first dimension.
-    !
-    ! B = diff(A, n) returns the nth difference by applying the diff(A)
-    ! operator recursively n times.
-    !
-    ! B = diff(A, dim) returns differences between adjacent elements of
-    ! array A along the dimension given by dim.
-    !
-    ! B = diff(A, n, dim) returns the nth difference along the dimension
-    ! given by dim by applying the diff(A, dim) operator recursively
-    ! n times.
-
-    function diff1(x, n)
-        real(kind=RPRE), dimension(:), allocatable :: diff1
-        real(kind=RPRE), dimension(:), intent(in) :: x
-        integer(kind=IPRE), intent(in), optional :: n
-        integer(kind=IPRE) :: opt_n, i
-
-        opt_n = 1
-        if (present(n)) opt_n = n
-
-        diff1 = x
-        do i = 1, opt_n
-            diff1 = diff1(2:) - diff1(:size(diff1) - 1)
-        end do
-        return
-    end function diff1
-
-    function diff2(A, n, dim)
-        real(kind=RPRE), dimension(:, :), allocatable :: diff2
-        real(kind=RPRE), dimension(:, :), intent(in) :: A
-        integer(kind=IPRE), intent(in), optional :: n, dim
-        integer(kind=IPRE) :: opt_n, i
 
-        opt_n = 1
-        if (present(n)) opt_n = n
 
-        diff2 = A
-        if ((.not. present(dim)) .or. (dim == 1)) then
-            do i = 1, opt_n
-                diff2 = diff2(2:, :) - diff2(:size(diff2, 1) - 1, :)
-            end do
-        elseif (dim == 2) then
-            do i = 1, opt_n
-                diff2 = diff2(:, 2:) - diff2(:, :size(diff2, 2) - 1)
-            end do
-        end if
-        return
-    end function diff2
+
 
     ! find
     !-----------------------------------------------------------------------