From 64b7bddb48eb06268fc127e5a92f71cfe36b3549 Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Tue, 16 Sep 2025 20:35:37 +0200
Subject: [PATCH 01/11] Fixes from mkdocs warnings

---
 docs/SUMMARY.md                                             | 4 ++--
 docs/getting-started.md                                     | 2 +-
 .../Mathematical Notation/Effects, Penalty & Objective.md   | 2 +-
 docs/user-guide/Mathematical Notation/Flow.md               | 4 ++--
 docs/user-guide/Mathematical Notation/LinearConverter.md    | 2 +-
 docs/user-guide/Mathematical Notation/Storage.md            | 2 +-
 flixopt/core.py                                             | 1 -
 flixopt/plotting.py                                         | 6 +++---
 flixopt/results.py                                          | 4 ++--
 flixopt/solvers.py                                          | 6 ++++--
 mkdocs.yml                                                  | 1 -
 scripts/gen_ref_pages.py                                    | 2 +-
 12 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/docs/SUMMARY.md b/docs/SUMMARY.md
index d13dd8387..c7abf017a 100644
--- a/docs/SUMMARY.md
+++ b/docs/SUMMARY.md
@@ -1,7 +1,7 @@
 - [Home](index.md)
 - [Getting Started](getting-started.md)
-- [User Guide](user-guide/)
-- [Examples](examples/)
+- [User Guide](user-guide/index.md)
+- [Examples](examples/index.md)
 - [Contribute](contribute.md)
 - [API-Reference](api-reference/)
 - [Release Notes](changelog.md)
diff --git a/docs/getting-started.md b/docs/getting-started.md
index d163c156f..ecf4bad5e 100644
--- a/docs/getting-started.md
+++ b/docs/getting-started.md
@@ -38,5 +38,5 @@ Working with FlixOpt follows a general pattern:
 Now that you've installed FlixOpt and understand the basic workflow, you can:
 
 - Learn about the [core concepts of FlixOpt](user-guide/index.md)
-- Explore some [examples](examples/)
+- Explore some [examples](examples/index.md)
 - Check the [API reference](api-reference/index.md) for detailed documentation
diff --git a/docs/user-guide/Mathematical Notation/Effects, Penalty & Objective.md b/docs/user-guide/Mathematical Notation/Effects, Penalty & Objective.md
index 9e306394a..03983360c 100644
--- a/docs/user-guide/Mathematical Notation/Effects, Penalty & Objective.md	
+++ b/docs/user-guide/Mathematical Notation/Effects, Penalty & Objective.md	
@@ -113,7 +113,7 @@ With:
 - $\mathcal{T}$ being the set of all timesteps
 - $s_{l \rightarrow \Phi}$ being the share of element $l$ to the penalty
 
-At the moment, penalties only occur in [Buses](#buses)
+At the moment, penalties only occur in [Buses](Bus.md)
 
 ## Objective
 
diff --git a/docs/user-guide/Mathematical Notation/Flow.md b/docs/user-guide/Mathematical Notation/Flow.md
index 142904a1d..3afe21971 100644
--- a/docs/user-guide/Mathematical Notation/Flow.md	
+++ b/docs/user-guide/Mathematical Notation/Flow.md	
@@ -21,6 +21,6 @@ $$
 $$
 
 
-This mathematical Formulation can be extended or changed when using [OnOffParameters](#onoffparameters)
-to define the On/Off state of the Flow, or [InvestParameters](#investments),
+This mathematical Formulation can be extended or changed when using OnOffParameters
+to define the On/Off state of the Flow, or InvestParameters,
 which changes the size of the Flow from a constant to an optimization variable.
diff --git a/docs/user-guide/Mathematical Notation/LinearConverter.md b/docs/user-guide/Mathematical Notation/LinearConverter.md
index 124d37c8c..81f8c2abc 100644
--- a/docs/user-guide/Mathematical Notation/LinearConverter.md	
+++ b/docs/user-guide/Mathematical Notation/LinearConverter.md	
@@ -1,4 +1,4 @@
-[`LinearConverters`][flixopt.components.LinearConverter] define a ratio between incoming and outgoing [Flows](#flows).
+[`LinearConverters`][flixopt.components.LinearConverter] define a ratio between incoming and outgoing [Flows](Flow.md).
 
 $$ \label{eq:Linear-Transformer-Ratio}
     \sum_{f_{\text{in}} \in \mathcal F_{in}} \text a_{f_{\text{in}}}(\text{t}_i) \cdot p_{f_\text{in}}(\text{t}_i) = \sum_{f_{\text{out}} \in \mathcal F_{out}}  \text b_{f_\text{out}}(\text{t}_i) \cdot p_{f_\text{out}}(\text{t}_i)
diff --git a/docs/user-guide/Mathematical Notation/Storage.md b/docs/user-guide/Mathematical Notation/Storage.md
index 577f12150..63f01d198 100644
--- a/docs/user-guide/Mathematical Notation/Storage.md	
+++ b/docs/user-guide/Mathematical Notation/Storage.md	
@@ -1,5 +1,5 @@
 # Storages
-**Storages** have one incoming and one outgoing **[Flow](#flows)** with a charging and discharging efficiency.
+**Storages** have one incoming and one outgoing **[Flow](Flow.md)** with a charging and discharging efficiency.
 A storage has a state of charge $c(\text{t}_i)$ which is limited by its `size` $\text C$ and relative bounds $\eqref{eq:Storage_Bounds}$.
 
 $$ \label{eq:Storage_Bounds}
diff --git a/flixopt/core.py b/flixopt/core.py
index f002713f2..002fbab48 100644
--- a/flixopt/core.py
+++ b/flixopt/core.py
@@ -595,7 +595,6 @@ def create_time_series(
             data: The data to create the TimeSeries from.
             name: The name of the TimeSeries.
             needs_extra_timestep: Whether to create an additional timestep at the end of the timesteps.
-            The data to create the TimeSeries from.
 
         Returns:
             The created TimeSeries.
diff --git a/flixopt/plotting.py b/flixopt/plotting.py
index e4c440aaf..7dc5d872e 100644
--- a/flixopt/plotting.py
+++ b/flixopt/plotting.py
@@ -517,11 +517,11 @@ def heat_map_plotly(
         data: A DataFrame with the data to be visualized. The index will be used for the y-axis, and columns will be used for the x-axis.
             The values in the DataFrame will be represented as colors in the heatmap.
         color_map: The color scale to use for the heatmap. Default is 'viridis'. Plotly supports various color scales like 'Cividis', 'Inferno', etc.
+        title: The title of the heatmap. Default is an empty string.
+        xlabel: The label for the x-axis. Default is 'Period'.
+        ylabel: The label for the y-axis. Default is 'Step'.
         categorical_labels: If True, the x and y axes are treated as categorical data (i.e., the index and columns will not be interpreted as continuous data).
             Default is True. If False, the axes are treated as continuous, which may be useful for time series or numeric data.
-        show: Wether to show the figure after creation. (This includes saving the figure)
-        save: Wether to save the figure after creation (without showing)
-        path: Path to save the figure.
 
     Returns:
         A Plotly figure object containing the heatmap. This can be further customized and saved
diff --git a/flixopt/results.py b/flixopt/results.py
index 223e3708e..aaa2ff161 100644
--- a/flixopt/results.py
+++ b/flixopt/results.py
@@ -59,7 +59,7 @@ class CalculationResults:
     """
 
     @classmethod
-    def from_file(cls, folder: Union[str, pathlib.Path], name: str):
+    def from_file(cls, folder: Union[str, pathlib.Path], name: str) -> 'CalculationResults':
         """Create CalculationResults instance by loading from saved files.
 
         This method loads the calculation results from previously saved files,
@@ -100,7 +100,7 @@ def from_file(cls, folder: Union[str, pathlib.Path], name: str):
         )
 
     @classmethod
-    def from_calculation(cls, calculation: 'Calculation'):
+    def from_calculation(cls, calculation: 'Calculation') -> 'CalculationResults':
         """Create CalculationResults directly from a Calculation object.
 
         This method extracts the solution, flow system, and other relevant
diff --git a/flixopt/solvers.py b/flixopt/solvers.py
index aaf1641ce..40cc20df8 100644
--- a/flixopt/solvers.py
+++ b/flixopt/solvers.py
@@ -57,12 +57,14 @@ def _options(self) -> Dict[str, Any]:
 
 class HighsSolver(_Solver):
     """
+    HiGHS solver configuration.
+
     Args:
         mip_gap (float): Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
             and the lower bound, which is the theoretically optimal solution (LP)
         time_limit_seconds (int): Solver's time limit in seconds.
-        threads (int): Number of threads to use.
-        extra_options (str): Filename for saving the solver log.
+        extra_options (Dict[str, Any]): Additional solver options.
+        threads (Optional[int]): Number of threads to use. Defaults to None.
     """
 
     threads: Optional[int] = None
diff --git a/mkdocs.yml b/mkdocs.yml
index 6d1a476ff..98747d987 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -85,7 +85,6 @@ plugins:
   - include-markdown
   - mike:
       version_selector: true
-      default_version: latest
   - gen-files:
       scripts:
       - scripts/gen_ref_pages.py
diff --git a/scripts/gen_ref_pages.py b/scripts/gen_ref_pages.py
index 13894d10a..f2de8a701 100644
--- a/scripts/gen_ref_pages.py
+++ b/scripts/gen_ref_pages.py
@@ -47,7 +47,7 @@
     index_file.write('# API Reference\n\n')
     index_file.write(
         'This section contains the documentation for all modules and classes in flixopt.\n'
-        'For more information on how to use the classes and functions, see the [Concepts & Math](../concepts-and-math/index.md) section.\n'
+        'For more information on how to use the classes and functions, see the [User Guide](../user-guide/index.md) section.\n'
     )
 
 with mkdocs_gen_files.open(f'{api_dir}/SUMMARY.md', 'w') as nav_file:

From 9c01f88b82ac6d02cb6be259a64d7a7a24064c89 Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Tue, 16 Sep 2025 20:38:58 +0200
Subject: [PATCH 02/11] Fixes from mkdocs warnings

---
 flixopt/solvers.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/flixopt/solvers.py b/flixopt/solvers.py
index 40cc20df8..97cd7ae37 100644
--- a/flixopt/solvers.py
+++ b/flixopt/solvers.py
@@ -59,7 +59,7 @@ class HighsSolver(_Solver):
     """
     HiGHS solver configuration.
 
-    Args:
+    Attributes:
         mip_gap (float): Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
             and the lower bound, which is the theoretically optimal solution (LP)
         time_limit_seconds (int): Solver's time limit in seconds.

From cda3334dc5eba84f0c7082ae1e211a643b6ed83c Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Tue, 16 Sep 2025 20:41:21 +0200
Subject: [PATCH 03/11] Fixes from mkdocs warnings

---
 flixopt/solvers.py | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/flixopt/solvers.py b/flixopt/solvers.py
index 97cd7ae37..0cefb3d3e 100644
--- a/flixopt/solvers.py
+++ b/flixopt/solvers.py
@@ -14,10 +14,11 @@ class _Solver:
     """
     Abstract base class for solvers.
 
-    Attributes:
-        mip_gap (float): Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
+    Args:
+        mip_gap: Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
             and the lower bound, which is the theoretically optimal solution (LP)
-        logfile_name (str): Filename for saving the solver log.
+        time_limit_seconds: Solver's time limit in seconds.
+        extra_options: Additional solver options.
     """
 
     name: ClassVar[str]
@@ -39,10 +40,10 @@ def _options(self) -> Dict[str, Any]:
 class GurobiSolver(_Solver):
     """
     Args:
-        mip_gap (float): Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
+        mip_gap: Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
             and the lower bound, which is the theoretically optimal solution (LP)
-        time_limit_seconds (int): Solver's time limit in seconds.
-        extra_options (str): Filename for saving the solver log.
+        time_limit_seconds: Solver's time limit in seconds.
+        extra_options: Additional solver options.
     """
 
     name: ClassVar[str] = 'gurobi'
@@ -60,10 +61,10 @@ class HighsSolver(_Solver):
     HiGHS solver configuration.
 
     Attributes:
-        mip_gap (float): Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
+        mip_gap: Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
             and the lower bound, which is the theoretically optimal solution (LP)
-        time_limit_seconds (int): Solver's time limit in seconds.
-        extra_options (Dict[str, Any]): Additional solver options.
+        time_limit_seconds: Solver's time limit in seconds.
+        extra_options: Additional solver options.
         threads (Optional[int]): Number of threads to use. Defaults to None.
     """
 

From 352fbfaa68b53dde748294a7c64c6c2d0e48e03e Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Fri, 19 Sep 2025 09:39:02 +0200
Subject: [PATCH 04/11] Improve solver docstrings

---
 flixopt/solvers.py | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/flixopt/solvers.py b/flixopt/solvers.py
index 0cefb3d3e..2c14f9ff1 100644
--- a/flixopt/solvers.py
+++ b/flixopt/solvers.py
@@ -15,10 +15,9 @@ class _Solver:
     Abstract base class for solvers.
 
     Args:
-        mip_gap: Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
-            and the lower bound, which is the theoretically optimal solution (LP)
-        time_limit_seconds: Solver's time limit in seconds.
-        extra_options: Additional solver options.
+        mip_gap: Acceptable relative optimality gap in [0.0, 1.0].
+        time_limit_seconds: Time limit in seconds.
+        extra_options: Additional solver options merged into `options`.
     """
 
     name: ClassVar[str]
@@ -39,11 +38,12 @@ def _options(self) -> Dict[str, Any]:
 
 class GurobiSolver(_Solver):
     """
+    Gurobi solver configuration.
+
     Args:
-        mip_gap: Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
-            and the lower bound, which is the theoretically optimal solution (LP)
-        time_limit_seconds: Solver's time limit in seconds.
-        extra_options: Additional solver options.
+        mip_gap: Acceptable relative optimality gap in [0.0, 1.0]; mapped to Gurobi `MIPGap`.
+        time_limit_seconds: Time limit in seconds; mapped to Gurobi `TimeLimit`.
+        extra_options: Additional solver options merged into `options`.
     """
 
     name: ClassVar[str] = 'gurobi'
@@ -61,11 +61,10 @@ class HighsSolver(_Solver):
     HiGHS solver configuration.
 
     Attributes:
-        mip_gap: Solver's mip gap setting. The MIP gap describes the accepted (MILP) objective,
-            and the lower bound, which is the theoretically optimal solution (LP)
-        time_limit_seconds: Solver's time limit in seconds.
-        extra_options: Additional solver options.
-        threads (Optional[int]): Number of threads to use. Defaults to None.
+        mip_gap: Acceptable relative optimality gap in [0.0, 1.0]; mapped to HiGHS `mip_rel_gap`.
+        time_limit_seconds: Time limit in seconds; mapped to HiGHS `time_limit`.
+        extra_options: Additional solver options merged into `options`.
+        threads (Optional[int]): Number of threads to use. If None, HiGHS chooses.
     """
 
     threads: Optional[int] = None

From e57741a3989db838d71b4ccd7fb5c55ffc8fd306 Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Fri, 19 Sep 2025 10:30:00 +0200
Subject: [PATCH 05/11] Typos in Docs

---
 docs/SUMMARY.md                                    |  2 +-
 docs/getting-started.md                            |  2 +-
 .../Effects, Penalty & Objective.md                | 14 +++++++-------
 docs/user-guide/Mathematical Notation/Flow.md      |  6 +++---
 .../Mathematical Notation/LinearConverter.md       |  4 ++--
 5 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/docs/SUMMARY.md b/docs/SUMMARY.md
index c7abf017a..603694aac 100644
--- a/docs/SUMMARY.md
+++ b/docs/SUMMARY.md
@@ -3,5 +3,5 @@
 - [User Guide](user-guide/index.md)
 - [Examples](examples/index.md)
 - [Contribute](contribute.md)
-- [API-Reference](api-reference/)
+- [API Reference](api-reference/index.md)
 - [Release Notes](changelog.md)
diff --git a/docs/getting-started.md b/docs/getting-started.md
index ecf4bad5e..9af389755 100644
--- a/docs/getting-started.md
+++ b/docs/getting-started.md
@@ -19,7 +19,7 @@ This provides the core functionality with the HiGHS solver included.
 For all features including interactive network visualizations and time series aggregation:
 
 ```bash
-pip install "flixopt[full]""
+pip install "flixopt[full]"
 ```
 
 ## Basic Workflow
diff --git a/docs/user-guide/Mathematical Notation/Effects, Penalty & Objective.md b/docs/user-guide/Mathematical Notation/Effects, Penalty & Objective.md
index 03983360c..7da311c37 100644
--- a/docs/user-guide/Mathematical Notation/Effects, Penalty & Objective.md	
+++ b/docs/user-guide/Mathematical Notation/Effects, Penalty & Objective.md	
@@ -1,15 +1,15 @@
 ## Effects
-[`Effects`][flixopt.effects.Effect] are used to allocate things like costs, emissions, or other "effects" occuring in the system.
+[`Effects`][flixopt.effects.Effect] are used to allocate things like costs, emissions, or other "effects" occurring in the system.
 These arise from so called **Shares**, which originate from **Elements** like [Flows](Flow.md).
 
 **Example:**
 
 [`Flows`][flixopt.elements.Flow] have an attribute called `effects_per_flow_hour`, defining the effect amount of per flow hour.
-Assiziated effects could be:
+Associated effects could be:
 - costs - given in [€/kWh]...
 - ...or emissions - given in [kg/kWh].
 -
-Effects are allocated seperatly for investments and operation.
+Effects are allocated separately for investments and operation.
 
 ### Shares to Effects
 
@@ -43,7 +43,7 @@ For example, the Effect "CO$_2$ emissions" (unit: kg)
 can cause an additional share to Effect "monetary costs" (unit: €).
 In this case, the factor $\text a_{x \rightarrow e}$ is the specific CO$_2$ price in €/kg. However, circular references have to be avoided.
 
-The overall sum of investment shares of an Effect $e$ is given by $\eqref{Effect_invest}$
+The overall sum of investment shares of an Effect $e$ is given by $\eqref{eq:Effect_invest}$
 
 $$ \label{eq:Effect_invest}
 E_{e, \text{inv}} =
@@ -68,8 +68,8 @@ With:
 
 - $\mathcal{L}$ being the set of all elements in the FlowSystem
 - $\mathcal{E}$ being the set of all effects in the FlowSystem
-- $\text r_{x \rightarrow e, \text{inv}}$ being the factor between the operation part of Effect $x$ and Effect $e$
-- $\text r_{x \rightarrow e, \text{op}}(\text{t}_i)$ being the factor between the invest part of Effect $x$ and Effect $e$
+- $\text r_{x \rightarrow e, \text{inv}}$ being the factor between the invest part of Effect $x$ and Effect $e$
+- $\text r_{x \rightarrow e, \text{op}}(\text{t}_i)$ being the factor between the operation part of Effect $x$ and Effect $e$
 
 - $\text{t}_i$ being the time step
 - $s_{l \rightarrow e, \text{inv}}$ being the share of element $l$ to the investment part of effect $e$
@@ -128,5 +128,5 @@ With:
 - $\Phi$ being the [Penalty](#penalty)
 
 This approach allows for a multi-criteria optimization using both...
- - ... the **Weigted Sum**Method, as the chosen **Objective Effect** can incorporate other Effects.
+ - ... the **Weighted Sum** method, as the chosen **Objective Effect** can incorporate other Effects.
  - ... the ($\epsilon$-constraint method) by constraining effects.
diff --git a/docs/user-guide/Mathematical Notation/Flow.md b/docs/user-guide/Mathematical Notation/Flow.md
index 3afe21971..ecf0b48c8 100644
--- a/docs/user-guide/Mathematical Notation/Flow.md	
+++ b/docs/user-guide/Mathematical Notation/Flow.md	
@@ -21,6 +21,6 @@ $$
 $$
 
 
-This mathematical Formulation can be extended or changed when using OnOffParameters
-to define the On/Off state of the Flow, or InvestParameters,
-which changes the size of the Flow from a constant to an optimization variable.
+This mathematical formulation can be extended by using [OnOffParameters](#onoffparameters)
+to define the on/off state of the Flow, or by using [InvestParameters](#investparameters)
+to change the size of the Flow from a constant to an optimization variable.
diff --git a/docs/user-guide/Mathematical Notation/LinearConverter.md b/docs/user-guide/Mathematical Notation/LinearConverter.md
index 81f8c2abc..bf1279c32 100644
--- a/docs/user-guide/Mathematical Notation/LinearConverter.md	
+++ b/docs/user-guide/Mathematical Notation/LinearConverter.md	
@@ -16,6 +16,6 @@ $$ \label{eq:Linear-Transformer-Ratio-simple}
     \text a(\text{t}_i) \cdot p_{f_\text{in}}(\text{t}_i) = p_{f_\text{out}}(\text{t}_i)
 $$
 
-where $\text a$ can be interpreted as the conversion efficiency of the **LinearTransformer**.
-#### Piecewise Concersion factors
+where $\text a$ can be interpreted as the conversion efficiency of the **LinearConverter**.
+#### Piecewise Conversion factors
 The conversion efficiency can be defined as a piecewise linear approximation. See [Piecewise](Piecewise.md) for more details.

From cf65be746a961b3e47758be36024ff0ff68ec16f Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Fri, 19 Sep 2025 10:31:03 +0200
Subject: [PATCH 06/11] Other typos

---
 flixopt/plotting.py | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/flixopt/plotting.py b/flixopt/plotting.py
index 7dc5d872e..38e564fa7 100644
--- a/flixopt/plotting.py
+++ b/flixopt/plotting.py
@@ -230,6 +230,7 @@ def with_plotly(
             - A dictionary mapping column names to colors (e.g., {'Column1': '#ff0000'})
         title: The title of the plot.
         ylabel: The label for the y-axis.
+        xlabel: The label for the x-axis.
         fig: A Plotly figure object to plot on. If not provided, a new figure will be created.
 
     Returns:
@@ -455,6 +456,9 @@ def heat_map_matplotlib(
         data: A DataFrame containing the data to be visualized. The index will be used for the y-axis, and columns will be used for the x-axis.
             The values in the DataFrame will be represented as colors in the heatmap.
         color_map: The colormap to use for the heatmap. Default is 'viridis'. Matplotlib supports various colormaps like 'plasma', 'inferno', 'cividis', etc.
+        title: The title of the plot.
+        xlabel: The label for the x-axis.
+        ylabel: The label for the y-axis.
         figsize: The size of the figure to create. Default is (12, 6), which results in a width of 12 inches and a height of 6 inches.
 
     Returns:
@@ -617,7 +621,7 @@ def heat_map_data_from_df(
     """
     Reshapes a DataFrame with a DateTime index into a 2D array for heatmap plotting,
     based on a specified sample rate.
-    If a non-valid combination of periods and steps per period is used, falls back to numerical indices
+    Only specific combinations of `periods` and `steps_per_period` are supported; invalid combinations raise an assertion.
 
     Args:
         df: A DataFrame with a DateTime index containing the data to reshape.
@@ -632,7 +636,7 @@ def heat_map_data_from_df(
         and columns representing each period.
     """
     assert pd.api.types.is_datetime64_any_dtype(df.index), (
-        'The index of the Dataframe must be datetime to transfrom it properly for a heatmap plot'
+        'The index of the DataFrame must be datetime to transform it properly for a heatmap plot'
     )
 
     # Define formats for different combinations of `periods` and `steps_per_period`
@@ -645,15 +649,15 @@ def heat_map_data_from_df(
         ('W', 'D'): ('%Y-w%W', '%w_%A'),  # week and day of week (with prefix for proper sorting)
         ('W', 'h'): ('%Y-w%W', '%w_%A %H:00'),
         ('D', 'h'): ('%Y-%m-%d', '%H:00'),  # Day and hour
-        ('D', '15min'): ('%Y-%m-%d', '%H:%MM'),  # Day and hour
+        ('D', '15min'): ('%Y-%m-%d', '%H:%M'),  # Day and minute
         ('h', '15min'): ('%Y-%m-%d %H:00', '%M'),  # minute of hour
         ('h', 'min'): ('%Y-%m-%d %H:00', '%M'),  # minute of hour
     }
 
-    minimum_time_diff_in_min = df.index.to_series().diff().min().total_seconds() / 60  # Smallest time_diff in minutes
+    diffs = df.index.to_series().diff().dropna()
+    minimum_time_diff_in_min = diffs.min().total_seconds() / 60 if not diffs.empty else float('inf')
     time_intervals = {'min': 1, '15min': 15, 'h': 60, 'D': 24 * 60, 'W': 7 * 24 * 60}
     if time_intervals[steps_per_period] > minimum_time_diff_in_min:
-        time_intervals[steps_per_period]
         logger.warning(
             f'To compute the heatmap, the data was aggregated from {minimum_time_diff_in_min:.2f} min to '
             f'{time_intervals[steps_per_period]:.2f} min. Mean values are displayed.'
@@ -675,7 +679,7 @@ def heat_map_data_from_df(
 
     resampled_data['period'] = resampled_data.index.strftime(period_format)
     resampled_data['step'] = resampled_data.index.strftime(step_format)
-    if '%w_%A' in step_format:  # SHift index of strings to ensure proper sorting
+    if '%w_%A' in step_format:  # Shift index of strings to ensure proper sorting
         resampled_data['step'] = resampled_data['step'].apply(
             lambda x: x.replace('0_Sunday', '7_Sunday') if '0_Sunday' in x else x
         )
@@ -1326,7 +1330,7 @@ def export_figure(
         elif save and show:
             plotly.offline.plot(fig, filename=str(filename))
         elif save and not show:
-            fig.write_html(filename)
+            fig.write_html(str(filename))
         return figure_like
 
     elif isinstance(figure_like, tuple):

From 08ee427dedaed5d6bcd8cbbbc4319c9510a65fa8 Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Fri, 19 Sep 2025 10:33:28 +0200
Subject: [PATCH 07/11] Fix docs link

---
 docs/SUMMARY.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/SUMMARY.md b/docs/SUMMARY.md
index 603694aac..753b137b3 100644
--- a/docs/SUMMARY.md
+++ b/docs/SUMMARY.md
@@ -1,6 +1,6 @@
 - [Home](index.md)
 - [Getting Started](getting-started.md)
-- [User Guide](user-guide/index.md)
+- [User Guide](user-guide/)
 - [Examples](examples/index.md)
 - [Contribute](contribute.md)
 - [API Reference](api-reference/index.md)

From 2a995f2a7ef3bcc7519d90f19e7a98506af4a1cc Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Sat, 20 Sep 2025 08:54:57 +0200
Subject: [PATCH 08/11] Fix docs link

---
 docs/user-guide/Mathematical Notation/Flow.md             | 4 ++--
 docs/user-guide/Mathematical Notation/InvestParameters.md | 3 +++
 docs/user-guide/Mathematical Notation/OnOffParameters.md  | 3 +++
 3 files changed, 8 insertions(+), 2 deletions(-)
 create mode 100644 docs/user-guide/Mathematical Notation/InvestParameters.md
 create mode 100644 docs/user-guide/Mathematical Notation/OnOffParameters.md

diff --git a/docs/user-guide/Mathematical Notation/Flow.md b/docs/user-guide/Mathematical Notation/Flow.md
index ecf0b48c8..78135e822 100644
--- a/docs/user-guide/Mathematical Notation/Flow.md	
+++ b/docs/user-guide/Mathematical Notation/Flow.md	
@@ -21,6 +21,6 @@ $$
 $$
 
 
-This mathematical formulation can be extended by using [OnOffParameters](#onoffparameters)
-to define the on/off state of the Flow, or by using [InvestParameters](#investparameters)
+This mathematical formulation can be extended by using [OnOffParameters](./OnOffParameters.md)
+to define the on/off state of the Flow, or by using [InvestParameters](./InvestParameters.md)
 to change the size of the Flow from a constant to an optimization variable.
diff --git a/docs/user-guide/Mathematical Notation/InvestParameters.md b/docs/user-guide/Mathematical Notation/InvestParameters.md
new file mode 100644
index 000000000..d3cd4f81e
--- /dev/null
+++ b/docs/user-guide/Mathematical Notation/InvestParameters.md	
@@ -0,0 +1,3 @@
+# InvestParameters
+
+This is a work in progress.
diff --git a/docs/user-guide/Mathematical Notation/OnOffParameters.md b/docs/user-guide/Mathematical Notation/OnOffParameters.md
new file mode 100644
index 000000000..ca22d7d33
--- /dev/null
+++ b/docs/user-guide/Mathematical Notation/OnOffParameters.md	
@@ -0,0 +1,3 @@
+# OnOffParameters
+
+This is a work in progress.

From 2e58d7198356a90491652b93c828ac33f6ee7b23 Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Sun, 21 Sep 2025 20:51:04 +0200
Subject: [PATCH 09/11] Revert some changes

---
 docs/SUMMARY.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/SUMMARY.md b/docs/SUMMARY.md
index 753b137b3..df8f39d9a 100644
--- a/docs/SUMMARY.md
+++ b/docs/SUMMARY.md
@@ -1,7 +1,7 @@
 - [Home](index.md)
 - [Getting Started](getting-started.md)
 - [User Guide](user-guide/)
-- [Examples](examples/index.md)
+- [Examples](examples/)
 - [Contribute](contribute.md)
-- [API Reference](api-reference/index.md)
+- [API Reference](api-reference/)
 - [Release Notes](changelog.md)

From 02c2bbb59df7ce938f76a22d7a98bfbd28636f16 Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Sun, 21 Sep 2025 20:58:56 +0200
Subject: [PATCH 10/11] Revert some changes

---
 flixopt/plotting.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/flixopt/plotting.py b/flixopt/plotting.py
index 38e564fa7..3abb30842 100644
--- a/flixopt/plotting.py
+++ b/flixopt/plotting.py
@@ -655,7 +655,7 @@ def heat_map_data_from_df(
     }
 
     diffs = df.index.to_series().diff().dropna()
-    minimum_time_diff_in_min = diffs.min().total_seconds() / 60 if not diffs.empty else float('inf')
+    minimum_time_diff_in_min = diffs.min().total_seconds() / 60
     time_intervals = {'min': 1, '15min': 15, 'h': 60, 'D': 24 * 60, 'W': 7 * 24 * 60}
     if time_intervals[steps_per_period] > minimum_time_diff_in_min:
         logger.warning(

From dbfcbe2344d4579323247afbf023cbf2e1ae2476 Mon Sep 17 00:00:00 2001
From: FBumann <117816358+FBumann@users.noreply.github.com>
Date: Sun, 21 Sep 2025 21:01:33 +0200
Subject: [PATCH 11/11] Add entry to CHANGELOG.md

---
 CHANGELOG.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e73ce1521..ed73c2d39 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -42,6 +42,8 @@ Until here -->
 ### Fixed
 - Fix color scheme selection in network_app; color pickers now update when a scheme is selected.
 - Fix error handling in network visualization if networkx is not installed.
+- Fix broken links in docs.
+- Fix missing args in docstrings in `plotting.py`, `solvers.py`, and `core.py`.
 
 ### Known Issues