Merge branch 'master' into revival_string_list

Author: aman-godara

Diff for: README.md

@@ -98,7 +98,7 @@ The following combinations are known to work, but they are not tested in the CI:
 
 Name | Version | Platform | Architecture
 --- | --- | --- | ---
-GCC Fortran (MinGW) | 8.4.0, 9.3.0, 10.2.0 | Windows 10 | x86_64, i686
+GCC Fortran (MinGW) | 9.3.0, 10.2.0, 11.2.0 | Windows 10 | x86_64, i686
 
 We try to test as many available compilers and platforms as possible.
 A list of tested compilers which are currently not working and the respective issue are listed below.

Diff for: doc/specs/stdlib_ascii.md

@@ -212,42 +212,4 @@ program demo_reverse
     implicit none
     print'(a)', reverse("Hello, World!") ! returns "!dlroW ,olleH"
 end program demo_reverse
-```
-
-### `to_string`
-
-#### Status
-
-Experimental
-
-#### Description
-
-Create a character string representing the value of the provided variable.
-
-#### Syntax
-
-`res = [[stdlib_ascii(module):to_string(interface)]] (string)`
-
-#### Class
-
-Pure function.
-
-#### Argument
-
-`val`: shall be an intrinsic integer or logical type. It is an `intent(in)` argument.
-
-#### Result value
-
-The result is an intrinsic character type.
-
-#### Example
-
-```fortran
-program demo_string_value
-    use stdlib_ascii, only : to_string
-    implicit none
-    print'(a)', to_string(-3) ! returns "-3"
-    print'(a)', to_string(.true.) ! returns "T"
-    print'(a)', to_string(42) ! returns "42"
-end program demo_string_value
-```
+```

Diff for: doc/specs/stdlib_math.md

@@ -275,3 +275,71 @@ program demo_logspace_rstart_cbase
 
 end program demo_logspace_rstart_cbase
 ```
+## `arange`
+
+### Status
+
+Experimental
+
+### Class
+
+Pure function.
+
+### Description
+
+Creates a one-dimensional `array` of the `integer/real` type with fixed-spaced values of given spacing, within a given interval.
+
+### Syntax
+
+`result = [[stdlib_math(module):arange(interface)]](start [, end, step])`
+
+### Arguments
+
+All arguments should be the same type and kind.
+
+`start`: Shall be an `integer/real` scalar.
+This is an `intent(in)` argument.  
+The default `start` value is `1`.
+
+`end`: Shall be an `integer/real` scalar.
+This is an `intent(in)` and `optional` argument.  
+The default `end` value is the inputted `start` value.
+
+`step`: Shall be an `integer/real` scalar and large than `0`. 
+This is an `intent(in)` and `optional` argument.   
+The default `step` value is `1`.
+
+#### Warning
+If `step = 0`, the `step` argument will be corrected to `1/1.0` by the internal process of the `arange` function.   
+If `step < 0`, the `step` argument will be corrected to `abs(step)` by the internal process of the `arange` function. 
+
+### Return value
+
+Returns a one-dimensional `array` of fixed-spaced values.
+
+For `integer` type arguments, the length of the result vector is `(end - start)/step + 1`.  
+For `real` type arguments, the length of the result vector is `floor((end - start)/step) + 1`.
+
+### Example
+
+```fortran
+program demo_math_arange
+    use stdlib_math, only: arange
+
+    print *, arange(3)                 !! [1,2,3]
+    print *, arange(-1)                !! [1,0,-1]
+    print *, arange(0,2)               !! [0,1,2]
+    print *, arange(1,-1)              !! [1,0,-1]
+    print *, arange(0, 2, 2)           !! [0,2]
+
+    print *, arange(3.0)               !! [1.0,2.0,3.0]
+    print *, arange(0.0,5.0)           !! [0.0,1.0,2.0,3.0,4.0,5.0]
+    print *, arange(0.0,6.0,2.5)       !! [0.0,2.5,5.0]
+
+    print *, (1.0,1.0)*arange(3)       !! [(1.0,1.0),(2.0,2.0),[3.0,3.0]]
+
+    print *, arange(0.0,2.0,-2.0)      !! [0.0,2.0].     Not recommended: `step` argument is negative!
+    print *, arange(0.0,2.0,0.0)       !! [0.0,1.0,2.0]. Not recommended: `step` argument is zero!
+
+end program demo_math_arange
+```

Diff for: doc/specs/stdlib_strings.md

@@ -538,3 +538,72 @@ program demo_count
 
 end program demo_count
 ```
+
+<!-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -->
+### `to_string`
+
+#### Description
+
+Format or transfer a `integer/real/complex/logical` scalar as a string.  
+Input a wrong `format` that cause the internal-IO to fail, the result value is a string of `[*]`.
+
+#### Syntax
+
+`string = [[stdlib_strings(module):to_string(interface)]] (value [, format])`
+
+#### Status
+
+Experimental
+
+#### Class
+
+Pure function.
+
+#### Argument
+
+- `value`: Shall be an `integer/real/complex/logical` scalar.
+  This is an `intent(in)` argument.
+- `format`: Shall be a `character(len=*)` scalar like `'(F6.2)'` or just `'F6.2'`.
+  This is an `intent(in)` and `optional` argument.  
+  Contains the edit descriptor to format `value` into a string, for example `'(F6.2)'` or `'(f6.2)'`. 
+  `to_string` will automatically enclose `format` in a set of parentheses, so passing `F6.2` or `f6.2` as `format` is possible as well.
+  
+#### Result value
+
+The result is an `allocatable` length `character` scalar with up to `128` cached `character` length.
+
+#### Example
+
+```fortran
+program demo_to_string
+    use stdlib_strings, only: to_string
+
+    !> Example for `complex` type
+    print *, to_string((1, 1))              !! "(1.00000000,1.00000000)"
+    print *, to_string((1, 1), '(F6.2)')    !! "(  1.00,  1.00)"
+    print *, to_string((1000, 1), '(ES0.2)'), to_string((1000, 1), '(SP,F6.3)')     
+                    !! "(1.00E+3,1.00)""(******,+1.000)"
+                    !! Too narrow formatter for real number
+                    !! Normal demonstration(`******` from Fortran Standard)
+
+    !> Example for `integer` type
+    print *, to_string(-3)                  !! "-3"
+    print *, to_string(42, '(I4)')          !! "  42"
+    print *, to_string(1, '(I0.4)'), to_string(2, '(B4)')           !! "0001""  10"  
+
+    !> Example for `real` type
+    print *, to_string(1.)                  !! "1.00000000"
+    print *, to_string(1., '(F6.2)')        !! "  1.00" 
+    print *, to_string(1., 'F6.2')          !! "  1.00" 
+    print *, to_string(1., '(SP,ES9.2)'), to_string(1, '(F7.3)')    !! "+1.00E+00""[*]"
+                    !! 1 wrong demonstration (`[*]` from `to_string`)
+
+    !> Example for `logical` type
+    print *, to_string(.true.)              !! "T"
+    print *, to_string(.true., '(L2)')      !! " T"
+    print *, to_string(.true., 'L2')        !! " T"
+    print *, to_string(.false., '(I5)')     !! "[*]"
+                    !! 1 wrong demonstrations(`[*]` from `to_string`)
+
+end program demo_to_string
+```

Diff for: src/CMakeLists.txt

@@ -32,7 +32,11 @@ set(fppFiles
     stdlib_math.fypp
     stdlib_math_linspace.fypp
     stdlib_math_logspace.fypp
+    stdlib_math_arange.fypp
     stdlib_string_type.fypp
+    stdlib_string_type_constructor.fypp
+    stdlib_strings_to_string.fypp
+    stdlib_strings.fypp
 )
 
 
@@ -51,7 +55,6 @@ set(SRC
     stdlib_error.f90
     stdlib_kinds.f90
     stdlib_logger.f90
-    stdlib_strings.f90
     stdlib_system.F90
     stdlib_specialfunctions.f90
     stdlib_specialfunctions_legendre.f90

Diff for: src/Makefile.manual

@@ -1,4 +1,4 @@
-SRCFYPP =\
+SRCFYPP = \
         stdlib_ascii.fypp \
         stdlib_bitsets_64.fypp \
         stdlib_bitsets_large.fypp \
@@ -7,6 +7,7 @@ SRCFYPP =\
         stdlib_linalg.fypp \
         stdlib_linalg_diag.fypp \
         stdlib_linalg_outer_product.fypp \
+        stdlib_math_arange.fypp \
         stdlib_optval.fypp \
         stdlib_quadrature.fypp \
         stdlib_quadrature_trapz.fypp \
@@ -26,10 +27,13 @@ SRCFYPP =\
         stdlib_stats_moment_scalar.fypp \
         stdlib_stats_var.fypp \
         stdlib_math.fypp \
-		stdlib_math_linspace.fypp \
-		stdlib_math_logspace.fypp \
+	stdlib_math_linspace.fypp \
+	stdlib_math_logspace.fypp \
         stdlib_stats_distribution_PRNG.fypp \
-        stdlib_string_type.fypp
+        stdlib_string_type.fypp \
+        stdlib_string_type_constructor.fypp \
+        stdlib_strings.fypp \
+        stdlib_strings_to_string.fypp
 
 SRC = f18estop.f90 \
       stdlib_error.f90 \
@@ -77,84 +81,91 @@ stdlib_error.o: stdlib_optval.o
 stdlib_specialfunctions.o: stdlib_kinds.o
 stdlib_specialfunctions_legendre.o: stdlib_kinds.o stdlib_specialfunctions.o
 stdlib_io.o: \
-	stdlib_ascii.o \
-	stdlib_error.o \
-	stdlib_optval.o \
-	stdlib_kinds.o
+    stdlib_ascii.o \
+    stdlib_error.o \
+    stdlib_optval.o \
+    stdlib_kinds.o \
+    stdlib_ascii.o
 stdlib_linalg.o: \
-	stdlib_kinds.o
+    stdlib_kinds.o
 stdlib_linalg_diag.o: \
-	stdlib_linalg.o \
-	stdlib_kinds.o
+    stdlib_linalg.o \
+    stdlib_kinds.o
 stdlib_logger.o: stdlib_ascii.o stdlib_optval.o
 stdlib_optval.o: stdlib_kinds.o
 stdlib_quadrature.o: stdlib_kinds.o
-
 stdlib_quadrature_gauss.o: stdlib_kinds.o stdlib_quadrature.o
-
 stdlib_quadrature_simps.o: \
-	stdlib_quadrature.o \
-	stdlib_error.o \
-	stdlib_kinds.o
+    stdlib_quadrature.o \
+    stdlib_error.o \
+    stdlib_kinds.o
 stdlib_quadrature_trapz.o: \
-	stdlib_quadrature.o \
-	stdlib_error.o \
-	stdlib_kinds.o
+    stdlib_quadrature.o \
+    stdlib_error.o \
+    stdlib_kinds.o
 stdlib_sorting.o: \
-	stdlib_kinds.o \
-	stdlib_string_type.o
+    stdlib_kinds.o \
+    stdlib_string_type.o
 stdlib_sorting_ord_sort.o: \
-	stdlib_sorting.o
+    stdlib_sorting.o
 stdlib_sorting_sort.o: \
-	stdlib_sorting.o
+    stdlib_sorting.o
 stdlib_sorting_sort_index.o: \
-	stdlib_sorting.o
+    stdlib_sorting.o
 stdlib_stats.o: \
-	stdlib_kinds.o
+    stdlib_kinds.o
 stdlib_stats_corr.o: \
-	stdlib_optval.o \
-	stdlib_kinds.o \
-	stdlib_stats.o
+    stdlib_optval.o \
+    stdlib_kinds.o \
+    stdlib_stats.o
 stdlib_stats_cov.o: \
-	stdlib_optval.o \
-	stdlib_kinds.o \
-	stdlib_stats.o
+    stdlib_optval.o \
+    stdlib_kinds.o \
+    stdlib_stats.o
 stdlib_stats_mean.o: \
-	stdlib_optval.o \
-	stdlib_kinds.o \
-	stdlib_stats.o
+    stdlib_optval.o \
+    stdlib_kinds.o \
+    stdlib_stats.o
 stdlib_stats_median.o: \
-	stdlib_optval.o \
-	stdlib_kinds.o \
-	stdlib_sorting.o \
-	stdlib_stats.o
+    stdlib_optval.o \
+    stdlib_kinds.o \
+    stdlib_sorting.o \
+    stdlib_stats.o
 stdlib_stats_moment.o: \
-	stdlib_optval.o \
-	stdlib_kinds.o \
-	stdlib_stats.o
+    stdlib_optval.o \
+    stdlib_kinds.o \
+    stdlib_stats.o
 stdlib_stats_moment_all.o: \
-	stdlib_stats_moment.o
+    stdlib_stats_moment.o
 stdlib_stats_moment_mask.o: \
-	stdlib_stats_moment.o
+    stdlib_stats_moment.o
 stdlib_stats_moment_scalar.o: \
-	stdlib_stats_moment.o
+    stdlib_stats_moment.o
 stdlib_stats_var.o: \
-	stdlib_optval.o \
-	stdlib_kinds.o \
-	stdlib_stats.o
+    stdlib_optval.o \
+    stdlib_kinds.o \
+    stdlib_stats.o
 stdlib_stats_distribution_PRNG.o: \
-        stdlib_kinds.o \
-	stdlib_error.o
+    stdlib_kinds.o \
+    stdlib_error.o
 stdlib_string_type.o: stdlib_ascii.o \
     stdlib_kinds.o
+stdlib_string_type_constructor.o: stdlib_string_type.o \
+    stdlib_strings_to_string.o \
+    stdlib_strings.o
 stdlib_strings.o: stdlib_ascii.o \
     stdlib_string_type.o \
-	stdlib_optval.o
-stdlib_math.o: stdlib_kinds.o
+    stdlib_optval.o \
+    stdlib_kinds.o
+stdlib_strings_to_string.o: stdlib_strings.o
+stdlib_math.o: stdlib_kinds.o \
+    stdlib_optval.o
 stdlib_math_linspace.o: \
-	stdlib_math.o
+    stdlib_math.o
 stdlib_math_logspace.o: \
-	stdlib_math_linspace.o
+    stdlib_math_linspace.o
+stdlib_math_arange.o: \
+    stdlib_math.o
 stdlib_linalg_outer_product.o: stdlib_linalg.o
 stdlib_stringlist_type.o: stdlib_string_type.o \
     stdlib_math.o \