Feat/add dijkerman1988

docs/src/ptf-catalog/sources/dijkerman1988.md

@@ -0,0 +1,101 @@
+---
+# @generated by ptfkit-codegen; DO NOT EDIT.
+
+title: PTF source dijkerman1988
+nav-title: dijkerman1988
+---
+
+# Dijkerman (1988), texture-based gravimetric water retention for Sierra Leone soils.
+
+## Source
+
+Dijkerman, J. C. (1988). An Ustult-Aquult-Tropept catena in Sierra Leone, West Africa, II. Land qualities and land evaluation. Geoderma, 42, 29-49.
+
+[DOI: 10.1016/0016-7061(88)90021-3](https://doi.org/10.1016/0016-7061(88)90021-3)
+
+## Scope
+
+**Territory:** Sierra Leone, West Africa
+
+**Dataset:** 166 soil samples from 42 soil profiles reported by Odell et al. (1974). Samples with organic carbon greater than 4% were excluded from the regressions.
+
+## Functions
+
+### `calc_ptf_dijkerman1988`
+
+Estimate gravimetric water contents at 15 bar and one-third bar from texture.
+
+**Status:** `ready-for-implementation`
+
+**Prediction target:** Gravimetric water contents at 15 bar and one-third bar.
+
+#### Inputs
+
+| Name | Type | Unit | Domain | Description |
+| --- | --- | --- | --- | --- |
+| `clay` | `number` | % | 1.3 <= clay <= 66.6 | Clay content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. |
+| `sand` | `number` | % | 0.5 <= sand <= 96.4 | Sand content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. |
+
+#### Outputs
+
+| Name | Unit | Domain | Description |
+| --- | --- | --- | --- |
+| `water_content_15_bar` | % | — | Gravimetric moisture content at 15 bar, in weight percentage. |
+| `water_content_one_third_bar` | % | — | Gravimetric moisture content at one-third bar, in weight percentage. |
+
+!!! note
+
+    Sand, silt, and clay percentages must sum to 100; sand plus clay must not exceed 100.
+
+!!! note
+
+    The regression dataset excludes samples containing more than 4% organic carbon.
+
+!!! note
+
+    These are two point predictions, not a continuous retention curve.
+
+!!! warning
+
+    The paper describes these relationships as rough guides.
+
+!!! warning
+
+    One-third-bar moisture content may underestimate field capacity and available moisture in these soils.
+
+!!! warning
+
+    The observed marginal calibration ranges do not establish validity for every joint texture combination.
+
+### `calc_ptf_dijkerman1988_available_water`
+
+Estimate the gravimetric available moisture between one-third bar and 15 bar.
+
+**Status:** `ready-for-implementation`
+
+**Prediction target:** Gravimetric available moisture between one-third bar and 15 bar.
+
+#### Inputs
+
+| Name | Type | Unit | Domain | Description |
+| --- | --- | --- | --- | --- |
+| `clay` | `number` | % | 1.3 <= clay <= 66.6 | Clay content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. |
+| `silt` | `number` | % | 0 <= silt <= 100; 0.5 <= 100 - clay - silt <= 96.4 | Silt content by mass; sand, silt, and clay sum to 100%. No separate observed silt calibration range is supplied. |
+
+#### Outputs
+
+| Name | Unit | Domain | Description |
+| --- | --- | --- | --- |
+| `available_water` | % | — | Difference in gravimetric moisture contents, in weight percentage points. |
+
+!!! note
+
+    This estimates a gravimetric difference, not profile water storage or a volumetric fraction.
+
+!!! note
+
+    Use soil material with organic carbon at most 4% and physically consistent texture percentages.
+
+!!! warning
+
+    Available moisture estimated using one-third bar may be somewhat low according to the paper.

docs/src/ptf-catalog/sources/index.md

@@ -17,6 +17,7 @@ Each page describes the source, scope, inputs, outputs, status, and limitations
 | [Clapp and Hornberger (1978) representative soil hydraulic parameters by texture.](./clapp1978.md) | United States | 1 |
 | [Cosby et al. (1984), United States.](./cosby1984.md) | United States | 1 |
 | [Dharumarajan et al. (2019) hydraulic PTFs for the Karnataka Plateau.](./dharumarajan2019.md) | Karnataka Plateau, India | 5 |
+| [Dijkerman (1988), texture-based gravimetric water retention for Sierra Leone soils.](./dijkerman1988.md) | Sierra Leone, West Africa | 2 |
 | [Ferrer Julià et al. (2004), saturated-conductivity PTFs for Spanish soils.](./ferrerjulia2004.md) | Spanish mainland on the Iberian Peninsula | 41 |
 | [Point water-retention regressions for tropical Sri Lankan soils.](./gunarathna2019.md) | Tropical Sri Lanka. | 11 |
 | [Hodnett & Tomasella (2002), tropical-soil regressions for four van Genuchten parameters.](./hodnett2002.md) | Tropical soils between approximately 25 degrees N and 25 degrees S. | 1 |

docs/src/reference/c/functions.md

@@ -34,6 +34,8 @@ title: C function index
 | [`calc_ptf_dharumarajan2019_nkp_clay`](headers/dharumarajan2019.md#function-calc_ptf_dharumarajan2019_nkp_clay) | Estimate Northern Karnataka field capacity and wilting point from clay. | [`<ptfkit/dharumarajan2019.h>`](headers/dharumarajan2019.md) |
 | [`calc_ptf_dharumarajan2019_skp`](headers/dharumarajan2019.md#function-calc_ptf_dharumarajan2019_skp) | Estimate field capacity and wilting point for Southern Karnataka soils. | [`<ptfkit/dharumarajan2019.h>`](headers/dharumarajan2019.md) |
 | [`calc_ptf_dharumarajan2019_skp_clay`](headers/dharumarajan2019.md#function-calc_ptf_dharumarajan2019_skp_clay) | Estimate Southern Karnataka field capacity and wilting point from clay. | [`<ptfkit/dharumarajan2019.h>`](headers/dharumarajan2019.md) |
+| [`calc_ptf_dijkerman1988`](headers/dijkerman1988.md#function-calc_ptf_dijkerman1988) | Estimate gravimetric water contents at 15 bar and one-third bar from texture. | [`<ptfkit/dijkerman1988.h>`](headers/dijkerman1988.md) |
+| [`calc_ptf_dijkerman1988_available_water`](headers/dijkerman1988.md#function-calc_ptf_dijkerman1988_available_water) | Estimate the gravimetric available moisture between one-third bar and 15 bar. | [`<ptfkit/dijkerman1988.h>`](headers/dijkerman1988.md) |
 | [`calc_ptf_ferrerjulia2004_calcaric_fluvisol_sand`](headers/ferrerjulia2004.md#function-calc_ptf_ferrerjulia2004_calcaric_fluvisol_sand) | Estimate saturated conductivity for Calcaric Fluvisol from sand content. | [`<ptfkit/ferrerjulia2004.h>`](headers/ferrerjulia2004.md) |
 | [`calc_ptf_ferrerjulia2004_calcaric_fluvisol_texture_organic_matter`](headers/ferrerjulia2004.md#function-calc_ptf_ferrerjulia2004_calcaric_fluvisol_texture_organic_matter) | Estimate saturated conductivity for Calcaric Fluvisol from texture and organic matter. | [`<ptfkit/ferrerjulia2004.h>`](headers/ferrerjulia2004.md) |
 | [`calc_ptf_ferrerjulia2004_calcaric_regosol_sand`](headers/ferrerjulia2004.md#function-calc_ptf_ferrerjulia2004_calcaric_regosol_sand) | Estimate saturated conductivity for Calcaric Regosol from sand content. | [`<ptfkit/ferrerjulia2004.h>`](headers/ferrerjulia2004.md) |

docs/src/reference/c/headers/dijkerman1988.md

@@ -0,0 +1,117 @@
+---
+title: "dijkerman1988.h"
+---
+
+<!-- @generated by ptfkit-codegen; DO NOT EDIT. -->
+
+# `<ptfkit/dijkerman1988.h>`
+
+```c
+#include <ptfkit/dijkerman1988.h>
+```
+
+Dijkerman (1988), texture-based gravimetric water retention for Sierra Leone soils.
+
+## Source
+
+Dijkerman, J. C. (1988). An Ustult-Aquult-Tropept catena in Sierra Leone, West Africa, II. Land qualities and land evaluation. Geoderma, 42, 29-49.
+
+[DOI: 10.1016/0016-7061(88)90021-3](https://doi.org/10.1016/0016-7061(88)90021-3)
+
+## Scope
+
+**Territory:** Sierra Leone, West Africa
+
+**Dataset:** 166 soil samples from 42 soil profiles reported by Odell et al. (1974). Samples with organic carbon greater than 4% were excluded from the regressions.
+
+[PTF catalog page](../../../ptf-catalog/sources/dijkerman1988.md)
+
+## `dijkerman1988_water_content`
+
+```c
+typedef struct {
+    double water_content_15_bar;
+    double water_content_one_third_bar;
+ } dijkerman1988_water_content;
+```
+
+| Field | Description |
+| --- | --- |
+| `water_content_15_bar` | Gravimetric moisture content at 15 bar, in weight percentage. (%) |
+| `water_content_one_third_bar` | Gravimetric moisture content at one-third bar, in weight percentage. (%) |
+
+## Functions
+
+### `calc_ptf_dijkerman1988` {#function-calc_ptf_dijkerman1988}
+
+Estimate gravimetric water contents at 15 bar and one-third bar from texture.
+
+```c
+static inline dijkerman1988_water_content calc_ptf_dijkerman1988(double clay, double sand);
+```
+
+#### Parameters
+
+| Name | Direction | Description |
+| --- | --- | --- |
+| `clay` | in | Clay content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. (%) |
+| `sand` | in | Sand content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. (%) |
+
+#### Returns
+
+A `dijkerman1988_water_content` value.
+
+!!! note
+
+    Sand, silt, and clay percentages must sum to 100; sand plus clay must not exceed 100.
+
+!!! note
+
+    The regression dataset excludes samples containing more than 4% organic carbon.
+
+!!! note
+
+    These are two point predictions, not a continuous retention curve.
+
+!!! warning
+
+    The paper describes these relationships as rough guides.
+
+!!! warning
+
+    One-third-bar moisture content may underestimate field capacity and available moisture in these soils.
+
+!!! warning
+
+    The observed marginal calibration ranges do not establish validity for every joint texture combination.
+
+### `calc_ptf_dijkerman1988_available_water` {#function-calc_ptf_dijkerman1988_available_water}
+
+Estimate the gravimetric available moisture between one-third bar and 15 bar.
+
+```c
+static inline double calc_ptf_dijkerman1988_available_water(double clay, double silt);
+```
+
+#### Parameters
+
+| Name | Direction | Description |
+| --- | --- | --- |
+| `clay` | in | Clay content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. (%) |
+| `silt` | in | Silt content by mass; sand, silt, and clay sum to 100%. No separate observed silt calibration range is supplied. (%) |
+
+#### Returns
+
+Difference in gravimetric moisture contents, in weight percentage points. (%)
+
+!!! note
+
+    This estimates a gravimetric difference, not profile water storage or a volumetric fraction.
+
+!!! note
+
+    Use soil material with organic carbon at most 4% and physically consistent texture percentages.
+
+!!! warning
+
+    Available moisture estimated using one-third bar may be somewhat low according to the paper.

docs/src/reference/c/headers/ptfkit.md

@@ -21,6 +21,7 @@ This umbrella header aggregates every public ptfkit source header. Include an in
 - [`<ptfkit/clapp1978.h>`](clapp1978.md) — Clapp and Hornberger (1978) representative soil hydraulic parameters by texture.
 - [`<ptfkit/cosby1984.h>`](cosby1984.md) — Cosby et al. (1984), United States.
 - [`<ptfkit/dharumarajan2019.h>`](dharumarajan2019.md) — Dharumarajan et al. (2019) hydraulic PTFs for the Karnataka Plateau.
+- [`<ptfkit/dijkerman1988.h>`](dijkerman1988.md) — Dijkerman (1988), texture-based gravimetric water retention for Sierra Leone soils.
 - [`<ptfkit/ferrerjulia2004.h>`](ferrerjulia2004.md) — Ferrer Julià et al. (2004), saturated-conductivity PTFs for Spanish soils.
 - [`<ptfkit/gunarathna2019.h>`](gunarathna2019.md) — Point water-retention regressions for tropical Sri Lankan soils.
 - [`<ptfkit/hodnett2002.h>`](hodnett2002.md) — Hodnett & Tomasella (2002), tropical-soil regressions for four van Genuchten parameters.

docs/src/reference/c/index.md

@@ -18,6 +18,7 @@ ptfkit's C API is organized around installed headers.
 - [`<ptfkit/clapp1978.h>`](headers/clapp1978.md) — Clapp and Hornberger (1978) representative soil hydraulic parameters by texture.
 - [`<ptfkit/cosby1984.h>`](headers/cosby1984.md) — Cosby et al. (1984), United States.
 - [`<ptfkit/dharumarajan2019.h>`](headers/dharumarajan2019.md) — Dharumarajan et al. (2019) hydraulic PTFs for the Karnataka Plateau.
+- [`<ptfkit/dijkerman1988.h>`](headers/dijkerman1988.md) — Dijkerman (1988), texture-based gravimetric water retention for Sierra Leone soils.
 - [`<ptfkit/ferrerjulia2004.h>`](headers/ferrerjulia2004.md) — Ferrer Julià et al. (2004), saturated-conductivity PTFs for Spanish soils.
 - [`<ptfkit/gunarathna2019.h>`](headers/gunarathna2019.md) — Point water-retention regressions for tropical Sri Lankan soils.
 - [`<ptfkit/hodnett2002.h>`](headers/hodnett2002.md) — Hodnett & Tomasella (2002), tropical-soil regressions for four van Genuchten parameters.

docs/src/reference/cpp/functions.md

@@ -34,6 +34,8 @@ title: C++ function index
 | [`ptfkit::dharumarajan2019::calc_ptf_dharumarajan2019_nkp_clay`](modules/dharumarajan2019.md#function-calc_ptf_dharumarajan2019_nkp_clay) | Estimate Northern Karnataka field capacity and wilting point from clay. | [`ptfkit.dharumarajan2019`](modules/dharumarajan2019.md) |
 | [`ptfkit::dharumarajan2019::calc_ptf_dharumarajan2019_skp`](modules/dharumarajan2019.md#function-calc_ptf_dharumarajan2019_skp) | Estimate field capacity and wilting point for Southern Karnataka soils. | [`ptfkit.dharumarajan2019`](modules/dharumarajan2019.md) |
 | [`ptfkit::dharumarajan2019::calc_ptf_dharumarajan2019_skp_clay`](modules/dharumarajan2019.md#function-calc_ptf_dharumarajan2019_skp_clay) | Estimate Southern Karnataka field capacity and wilting point from clay. | [`ptfkit.dharumarajan2019`](modules/dharumarajan2019.md) |
+| [`ptfkit::dijkerman1988::calc_ptf_dijkerman1988`](modules/dijkerman1988.md#function-calc_ptf_dijkerman1988) | Estimate gravimetric water contents at 15 bar and one-third bar from texture. | [`ptfkit.dijkerman1988`](modules/dijkerman1988.md) |
+| [`ptfkit::dijkerman1988::calc_ptf_dijkerman1988_available_water`](modules/dijkerman1988.md#function-calc_ptf_dijkerman1988_available_water) | Estimate the gravimetric available moisture between one-third bar and 15 bar. | [`ptfkit.dijkerman1988`](modules/dijkerman1988.md) |
 | [`ptfkit::ferrerjulia2004::calc_ptf_ferrerjulia2004_calcaric_fluvisol_sand`](modules/ferrerjulia2004.md#function-calc_ptf_ferrerjulia2004_calcaric_fluvisol_sand) | Estimate saturated conductivity for Calcaric Fluvisol from sand content. | [`ptfkit.ferrerjulia2004`](modules/ferrerjulia2004.md) |
 | [`ptfkit::ferrerjulia2004::calc_ptf_ferrerjulia2004_calcaric_fluvisol_texture_organic_matter`](modules/ferrerjulia2004.md#function-calc_ptf_ferrerjulia2004_calcaric_fluvisol_texture_organic_matter) | Estimate saturated conductivity for Calcaric Fluvisol from texture and organic matter. | [`ptfkit.ferrerjulia2004`](modules/ferrerjulia2004.md) |
 | [`ptfkit::ferrerjulia2004::calc_ptf_ferrerjulia2004_calcaric_regosol_sand`](modules/ferrerjulia2004.md#function-calc_ptf_ferrerjulia2004_calcaric_regosol_sand) | Estimate saturated conductivity for Calcaric Regosol from sand content. | [`ptfkit.ferrerjulia2004`](modules/ferrerjulia2004.md) |

docs/src/reference/cpp/index.md

@@ -18,6 +18,7 @@ ptfkit's C++ API is organized around C++23 modules.
 - [`ptfkit.clapp1978`](modules/clapp1978.md) — Clapp and Hornberger (1978) representative soil hydraulic parameters by texture.
 - [`ptfkit.cosby1984`](modules/cosby1984.md) — Cosby et al. (1984), United States.
 - [`ptfkit.dharumarajan2019`](modules/dharumarajan2019.md) — Dharumarajan et al. (2019) hydraulic PTFs for the Karnataka Plateau.
+- [`ptfkit.dijkerman1988`](modules/dijkerman1988.md) — Dijkerman (1988), texture-based gravimetric water retention for Sierra Leone soils.
 - [`ptfkit.ferrerjulia2004`](modules/ferrerjulia2004.md) — Ferrer Julià et al. (2004), saturated-conductivity PTFs for Spanish soils.
 - [`ptfkit.gunarathna2019`](modules/gunarathna2019.md) — Point water-retention regressions for tropical Sri Lankan soils.
 - [`ptfkit.hodnett2002`](modules/hodnett2002.md) — Hodnett & Tomasella (2002), tropical-soil regressions for four van Genuchten parameters.

docs/src/reference/cpp/modules/dijkerman1988.md

@@ -0,0 +1,122 @@
+---
+# @generated by ptfkit-codegen; DO NOT EDIT.
+
+title: C++ module ptfkit.dijkerman1988
+nav-title: ptfkit.dijkerman1988
+---
+
+# `ptfkit.dijkerman1988`
+
+```cpp
+import ptfkit.dijkerman1988;
+```
+
+**Exported namespace:** `ptfkit::dijkerman1988`
+
+Dijkerman (1988), texture-based gravimetric water retention for Sierra Leone soils.
+
+## Source
+
+Dijkerman, J. C. (1988). An Ustult-Aquult-Tropept catena in Sierra Leone, West Africa, II. Land qualities and land evaluation. Geoderma, 42, 29-49.
+
+[DOI: 10.1016/0016-7061(88)90021-3](https://doi.org/10.1016/0016-7061(88)90021-3)
+
+## Scope
+
+**Territory:** Sierra Leone, West Africa
+
+**Dataset:** 166 soil samples from 42 soil profiles reported by Odell et al. (1974). Samples with organic carbon greater than 4% were excluded from the regressions.
+
+[PTF catalog page](../../../ptf-catalog/sources/dijkerman1988.md)
+
+## `Dijkerman1988WaterContent`
+
+```cpp
+struct Dijkerman1988WaterContent {
+    double water_content_15_bar;
+    double water_content_one_third_bar;
+};
+```
+
+| Field | Description |
+| --- | --- |
+| `water_content_15_bar` | Gravimetric moisture content at 15 bar, in weight percentage. (%) |
+| `water_content_one_third_bar` | Gravimetric moisture content at one-third bar, in weight percentage. (%) |
+
+## Functions
+
+### `calc_ptf_dijkerman1988` {#function-calc_ptf_dijkerman1988}
+
+Estimate gravimetric water contents at 15 bar and one-third bar from texture.
+
+```cpp
+[[nodiscard]]
+inline Dijkerman1988WaterContent calc_ptf_dijkerman1988(double clay, double sand)
+```
+
+#### Parameters
+
+| Name | Description |
+| --- | --- |
+| `clay` | Clay content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. (%) |
+| `sand` | Sand content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. (%) |
+
+#### Returns
+
+A `Dijkerman1988WaterContent` value.
+
+!!! note
+
+    Sand, silt, and clay percentages must sum to 100; sand plus clay must not exceed 100.
+
+!!! note
+
+    The regression dataset excludes samples containing more than 4% organic carbon.
+
+!!! note
+
+    These are two point predictions, not a continuous retention curve.
+
+!!! warning
+
+    The paper describes these relationships as rough guides.
+
+!!! warning
+
+    One-third-bar moisture content may underestimate field capacity and available moisture in these soils.
+
+!!! warning
+
+    The observed marginal calibration ranges do not establish validity for every joint texture combination.
+
+### `calc_ptf_dijkerman1988_available_water` {#function-calc_ptf_dijkerman1988_available_water}
+
+Estimate the gravimetric available moisture between one-third bar and 15 bar.
+
+```cpp
+[[nodiscard]]
+inline double calc_ptf_dijkerman1988_available_water(double clay, double silt)
+```
+
+#### Parameters
+
+| Name | Description |
+| --- | --- |
+| `clay` | Clay content by mass. The supplied research notes report this observed calibration range from a reconstruction of Odell et al. (1974), Appendix B. (%) |
+| `silt` | Silt content by mass; sand, silt, and clay sum to 100%. No separate observed silt calibration range is supplied. (%) |
+
+#### Returns
+
+Difference in gravimetric moisture contents, in weight percentage points. (%)
+
+!!! note
+
+    This estimates a gravimetric difference, not profile water storage or a volumetric fraction.
+
+!!! note
+
+    Use soil material with organic carbon at most 4% and physically consistent texture percentages.
+
+!!! warning
+
+    Available moisture estimated using one-third bar may be somewhat low according to the paper.