From d8eabe769380c4f2db86d14ed592e3a614a2492b Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Tue, 10 Feb 2026 22:30:21 +0800
Subject: [PATCH 01/23] Add the Frame/Axis class for setting frame and axes

---
 pygmt/params/__init__.py         |   1 +
 pygmt/params/frame.py            | 120 +++++++++++++++++++++++++++++++
 pygmt/tests/test_params_frame.py |  88 +++++++++++++++++++++++
 3 files changed, 209 insertions(+)
 create mode 100644 pygmt/params/frame.py
 create mode 100644 pygmt/tests/test_params_frame.py

diff --git a/pygmt/params/__init__.py b/pygmt/params/__init__.py
index d1a00a7f5f2..43b83ab0131 100644
--- a/pygmt/params/__init__.py
+++ b/pygmt/params/__init__.py
@@ -3,5 +3,6 @@
 """
 
 from pygmt.params.box import Box
+from pygmt.params.frame import Axis, Frame
 from pygmt.params.pattern import Pattern
 from pygmt.params.position import Position
diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
new file mode 100644
index 00000000000..9281765d12c
--- /dev/null
+++ b/pygmt/params/frame.py
@@ -0,0 +1,120 @@
+"""
+The Axes, Axis, and Frame classes for specifying the frame.
+"""
+
+import dataclasses
+
+from pygmt.alias import Alias
+from pygmt.exceptions import GMTParameterError
+from pygmt.params.base import BaseParam
+
+
+@dataclasses.dataclass(repr=False)
+class Axis(BaseParam):
+    """
+    Class for setting up one axis of a plot.
+    """
+
+    # Specify the intervals for annotations, ticks, and gridlines.
+    annot: float | None = None
+    tick: float | None = None
+    grid: float | None = None
+    # The label for the axis [Default is no label].
+    label: str | None = None
+
+    @property
+    def _aliases(self):
+        return [
+            Alias(self.annot, name="annot", prefix="a"),
+            Alias(self.tick, name="tick", prefix="f"),
+            Alias(self.grid, name="grid", prefix="g"),
+            Alias(self.label, name="label", prefix="+l"),
+        ]
+
+
+@dataclasses.dataclass(repr=False)
+class _Axes(BaseParam):
+    """
+    A private class to build the Axes part of the Frame class.
+    """
+
+    # Refer to the Frame class for full documentation.
+    axes: str | None = None
+    title: str | None = None
+
+    @property
+    def _aliases(self):
+        return [
+            Alias(self.axes, name="axes"),
+            Alias(self.title, name="title", prefix="+t"),
+        ]
+
+
+@dataclasses.dataclass(repr=False)
+class Frame(BaseParam):
+    """
+    Class for setting up the frame of a plot.
+    """
+
+    #: Specify which axes to draw and their attributes.
+    axes: str | None = None
+
+    #: The title string centered above the plot frame [Default is no title].
+    title: str | None = None
+
+    #: Specify the attributes for axes.
+    #:
+    #: The attributes for each axis can be specified in two ways:
+    #: #. specifying the same attributes for all axes using the ``axis`` parameter
+    #: #. specifying the attributes for each axis separately using the ``xaxis``,
+    #: ``yaxis``, ``zaxis`` parameter for the x-, y, and z-axes, respectively.
+    #:
+    #: GMT uses the notion of primary (the default) and secondary axes, while secondary
+    #: axes are optional and mostly used for time axes annotations. To specify the
+    #: attributes for the secondary axes, use the ``xaxis2``, ``yaxis2``, and ``zaxis2``
+    #: parameters.
+    axis: Axis | None = None
+    xaxis: Axis | None = None
+    yaxis: Axis | None = None
+    zaxis: Axis | None = None
+    xaxis2: Axis | None = None
+    yaxis2: Axis | None = None
+    zaxis2: Axis | None = None
+
+    def _validate(self):
+        """
+        Validate the parameters of the Frame class.
+        """
+        if self.axis is not None and any(
+            [self.xaxis, self.yaxis, self.zaxis, self.xaxis2, self.yaxis2, self.zaxis2]
+        ):
+            raise GMTParameterError(
+                conflicts_with=(
+                    "axis",
+                    ["xaxis", "yaxis", "zaxis", "xaxis2", "yaxis2", "zaxis2"],
+                ),
+                reason="Either 'axis' or the individual axis parameters can be set, but not both.",
+            )
+
+    @property
+    def _aliases(self):
+        return [
+            Alias(_Axes(axes=self.axes, title=self.title)),
+            Alias(self.axis, name="axis"),
+            Alias(self.xaxis, name="xaxis", prefix="px" if self.xaxis2 else "x"),
+            Alias(self.yaxis, name="yaxis", prefix="py" if self.yaxis2 else "y"),
+            Alias(self.zaxis, name="zaxis", prefix="pz" if self.zaxis2 else "z"),
+            Alias(self.xaxis2, name="xaxis2", prefix="sx"),
+            Alias(self.yaxis2, name="yaxis2", prefix="sy"),
+            Alias(self.zaxis2, name="zaxis2", prefix="sz"),
+        ]
+
+    def __iter__(self):
+        """
+        Iterate over the aliases of the class.
+
+        Yields
+        ------
+        The value of each alias in the class. None are excluded.
+        """
+        yield from (alias._value for alias in self._aliases if alias._value is not None)
diff --git a/pygmt/tests/test_params_frame.py b/pygmt/tests/test_params_frame.py
new file mode 100644
index 00000000000..f2471b5bece
--- /dev/null
+++ b/pygmt/tests/test_params_frame.py
@@ -0,0 +1,88 @@
+"""
+Test the Frame and Axis classes.
+"""
+
+from pygmt.params import Axis, Frame
+
+
+def test_params_axis():
+    """
+    Test the Axis class.
+    """
+    assert str(Axis(annot=True)) == "a"
+    assert str(Axis(annot=True, tick=True, grid=True)) == "afg"
+    assert str(Axis(annot=30, tick=15, grid=5)) == "a30f15g5"
+    assert str(Axis(annot=30, label="LABEL")) == "a30+lLABEL"
+
+
+def test_params_frame_only():
+    """
+    Test the Frame class.
+    """
+    assert str(Frame("WSen")) == "WSen"
+    assert str(Frame(axes="WSEN", title="My Title")) == "WSEN+tMy Title"
+
+
+def test_params_frame_axis():
+    """
+    Test the Frame class with uniform axis setting.
+    """
+    frame = Frame(axes="lrtb", title="My Title", axis=Axis(annot=30, tick=15, grid=10))
+    assert list(frame) == ["lrtb+tMy Title", "a30f15g10"]
+
+    frame = Frame(
+        axes="WSEN",
+        title="My Title",
+        axis=Axis(annot=True, tick=True, grid=True, label="LABEL"),
+    )
+    assert list(frame) == ["WSEN+tMy Title", "afg+lLABEL"]
+
+
+def test_params_frame_separate_axes():
+    """
+    Test the Frame class with separate axis settings.
+    """
+    frame = Frame(
+        axes="lrtb",
+        title="My Title",
+        xaxis=Axis(annot=10, tick=5, grid=2),
+        yaxis=Axis(annot=20, tick=10, grid=4),
+    )
+    assert list(frame) == ["lrtb+tMy Title", "xa10f5g2", "ya20f10g4"]
+
+    frame = Frame(
+        axes="WSEN",
+        title="My Title",
+        xaxis=Axis(annot=True, tick=True, grid=True, label="X-LABEL"),
+        yaxis=Axis(annot=True, tick=True, grid=True, label="Y-LABEL"),
+    )
+    assert list(frame) == ["WSEN+tMy Title", "xafg+lX-LABEL", "yafg+lY-LABEL"]
+
+
+def test_params_frame_separate_axis_secondary():
+    """
+    Test the Frame class with separate axis settings including secondary axes.
+    """
+    frame = Frame(
+        axes="lrtb",
+        title="My Title",
+        xaxis=Axis(annot=10, tick=5, grid=2),
+        xaxis2=Axis(annot=15, tick=7, grid=3),
+        yaxis=Axis(annot=20, tick=10, grid=4),
+        yaxis2=Axis(annot=25, tick=12, grid=5),
+    )
+    assert list(frame) == [
+        "lrtb+tMy Title",
+        "pxa10f5g2",
+        "pya20f10g4",
+        "sxa15f7g3",
+        "sya25f12g5",
+    ]
+
+    frame = Frame(
+        axes="WSEN",
+        title="My Title",
+        xaxis=Axis(annot=True, tick=True, grid=True, label="X-LABEL"),
+        yaxis=Axis(annot=True, tick=True, grid=True, label="Y-LABEL"),
+    )
+    assert list(frame) == ["WSEN+tMy Title", "xafg+lX-LABEL", "yafg+lY-LABEL"]

From a184f48876cf98ce1c15b774d789ca7aa6906006 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 20:31:10 +0800
Subject: [PATCH 02/23] Add to doc index

---
 doc/api/index.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/doc/api/index.rst b/doc/api/index.rst
index cce3f68f19d..3f874a9a2c2 100644
--- a/doc/api/index.rst
+++ b/doc/api/index.rst
@@ -216,7 +216,9 @@ Class-style Parameters
     :toctree: generated
     :template: autosummary/params.rst
 
+    Axis
     Box
+    Frame
     Pattern
     Position
 

From 3e1ad10d0f6ad9c93906a5659af087aa6f3caab9 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 21:30:58 +0800
Subject: [PATCH 03/23] Improve docstrings for 'axes'

---
 pygmt/params/frame.py | 52 ++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 47 insertions(+), 5 deletions(-)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index 9281765d12c..b99b8c90b28 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -15,13 +15,20 @@ class Axis(BaseParam):
     Class for setting up one axis of a plot.
     """
 
-    # Specify the intervals for annotations, ticks, and gridlines.
+    #: Specify the intervals for annotations, ticks, and gridlines.
     annot: float | None = None
     tick: float | None = None
     grid: float | None = None
-    # The label for the axis [Default is no label].
+    #: Label for the axis [Default is no label].
     label: str | None = None
 
+    #: A leading text prefix for the axis annotations (e.g., dollar sign for plots
+    #: related to money) [For Cartesian plots only].
+    prefix: str | None = None
+
+    #: Unix to append to the axis annotations [For Cartesian plots only].
+    unit: str | None = None
+
     @property
     def _aliases(self):
         return [
@@ -29,6 +36,8 @@ def _aliases(self):
             Alias(self.tick, name="tick", prefix="f"),
             Alias(self.grid, name="grid", prefix="g"),
             Alias(self.label, name="label", prefix="+l"),
+            Alias(self.prefix, name="prefix", prefix="+p"),
+            Alias(self.unit, name="unit", prefix="+u"),
         ]
 
 
@@ -38,7 +47,6 @@ class _Axes(BaseParam):
     A private class to build the Axes part of the Frame class.
     """
 
-    # Refer to the Frame class for full documentation.
     axes: str | None = None
     title: str | None = None
 
@@ -53,10 +61,44 @@ def _aliases(self):
 @dataclasses.dataclass(repr=False)
 class Frame(BaseParam):
     """
-    Class for setting up the frame of a plot.
+    Class for setting up the frame and axes of a plot.
     """
 
-    #: Specify which axes to draw and their attributes.
+    #: Controls which axes are drawn and whether they are annotated, using a combination
+    #: of the codes below. Axis ommitted from the set will not be drawn.
+    #:
+    #: For a 2-D plot, there are four axes: west, east, south, and north (or left,
+    #: right, bottom, top if you prefer); For a 3-D plot, there is an extra Z-axis.
+    #: They can be denoted by the following codes:
+    #:
+    #: - **W** (west), **E** (east), **S** (south), **N** (north), **Z**: Draw axes with
+    #:   both tick marks and annotations.
+    #: - **w** (west), **e** (east), **s** (south), **n** (north), **z**: Draw axes with
+    #:   tick marks but without annotations.
+    #: - **l** (left), **r** (right), **b** (bottom), **t** (top), **u** (up): Draw axes
+    #:   without tick marks or annotations.
+    #:
+    #: For examples:
+    #:
+    #: - ``"WS"``: Draw the west and south axes with both tick marks and annotations,
+    #:   but do not draw the east and north axes.
+    #: - ``"WSen"``: Draw the west and south axes with both tick marks and annotations,
+    #:    draw the east and north axes with tick marks but without annotations.
+    #: - ``"WSrt"``: Draw the west and south axes with both tick marks and annotations,
+    #:   draw the east and north axes without tick marks or annotations.
+    #: - ``"WSrtZ"``: Draw the west and south axes with both tick marks and annotations,
+    #:   draw the east and north axes without tick marks or annotations, and draw the
+    #:   z-axis with both tick marks and annotations.
+    #:
+    #: For a 3-D plot, if the z-axis code is specified, a single vertical axis will be
+    #: drawn at the most suitable corner by default. Append any combination of the
+    #: corner IDs from 1 to 4 to draw one or more vertical axes at the corresponding
+    #: corners. For example, `"WSrtZ1234"`.
+    #:
+    #: - **1**: the south-western (lower-left) corner
+    #: - **2**: the south-eastern (lower-right) corner
+    #: - **3**: the north-eastern (upper-right) corner
+    #: - **4**: the north-western (upper-left) corner
     axes: str | None = None
 
     #: The title string centered above the plot frame [Default is no title].

From 8f3a67ce765f88f992cfb7c522a17cba480f5a3e Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 21:40:27 +0800
Subject: [PATCH 04/23] Fix docstrings

---
 pygmt/params/frame.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index b99b8c90b28..69352b341a0 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -83,7 +83,7 @@ class Frame(BaseParam):
     #: - ``"WS"``: Draw the west and south axes with both tick marks and annotations,
     #:   but do not draw the east and north axes.
     #: - ``"WSen"``: Draw the west and south axes with both tick marks and annotations,
-    #:    draw the east and north axes with tick marks but without annotations.
+    #:   draw the east and north axes with tick marks but without annotations.
     #: - ``"WSrt"``: Draw the west and south axes with both tick marks and annotations,
     #:   draw the east and north axes without tick marks or annotations.
     #: - ``"WSrtZ"``: Draw the west and south axes with both tick marks and annotations,
@@ -93,7 +93,7 @@ class Frame(BaseParam):
     #: For a 3-D plot, if the z-axis code is specified, a single vertical axis will be
     #: drawn at the most suitable corner by default. Append any combination of the
     #: corner IDs from 1 to 4 to draw one or more vertical axes at the corresponding
-    #: corners. For example, `"WSrtZ1234"`.
+    #: corners (e.g., ``"WSrtZ1234"``):
     #:
     #: - **1**: the south-western (lower-left) corner
     #: - **2**: the south-eastern (lower-right) corner

From 5fbe28b87fe197eb42b7b6c9c033df3327038a3f Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 21:47:59 +0800
Subject: [PATCH 05/23] Add docstrings for annot/grid/tick

---
 pygmt/params/frame.py | 28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index 69352b341a0..77b20699952 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -15,10 +15,20 @@ class Axis(BaseParam):
     Class for setting up one axis of a plot.
     """
 
-    #: Specify the intervals for annotations, ticks, and gridlines.
-    annot: float | None = None
-    tick: float | None = None
-    grid: float | None = None
+    #: Specify the interval for annoations. It can be ``True`` to let GMT decide the
+    #: interval automatically; or a value to set a specific interval in the format of
+    #: *stride*[±*phase*][*unit*], where, *stride* is the interval, *phase* is the
+    #: offset to shift the annotations by that amount, and *unit* is one of the
+    #: :gmt-docs:`18 supported unit codes <reference/options.html#tbl-units>` related to
+    #: time intervals.
+    annot: float | bool = False
+
+    #: Specify the interval for ticks. Same format as ``annot``.
+    tick: float | bool = False
+
+    #: Specify the interval for gridlines. Same format as ``annot``.
+    grid: float | bool = False
+
     #: Label for the axis [Default is no label].
     label: str | None = None
 
@@ -104,12 +114,12 @@ class Frame(BaseParam):
     #: The title string centered above the plot frame [Default is no title].
     title: str | None = None
 
-    #: Specify the attributes for axes.
+    #: Specify the attributes for axes by an :class:`Axis` object.
     #:
-    #: The attributes for each axis can be specified in two ways:
-    #: #. specifying the same attributes for all axes using the ``axis`` parameter
-    #: #. specifying the attributes for each axis separately using the ``xaxis``,
-    #: ``yaxis``, ``zaxis`` parameter for the x-, y, and z-axes, respectively.
+    #: The attributes for each axis can be specified in two ways: (1) specifying the
+    #: same attributes for all axes using the ``axis`` parameter; (2) specifying the
+    #: attributes for each axis separately using the ``xaxis``, ``yaxis``, ``zaxis``
+    #: parameter for the x-, y, and z-axes, respectively.
     #:
     #: GMT uses the notion of primary (the default) and secondary axes, while secondary
     #: axes are optional and mostly used for time axes annotations. To specify the

From d320711ac5838cc04564c5606873fb014e513a59 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 21:52:05 +0800
Subject: [PATCH 06/23] Add one more test

---
 pygmt/tests/test_params_frame.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pygmt/tests/test_params_frame.py b/pygmt/tests/test_params_frame.py
index f2471b5bece..55a5f58f36b 100644
--- a/pygmt/tests/test_params_frame.py
+++ b/pygmt/tests/test_params_frame.py
@@ -13,6 +13,7 @@ def test_params_axis():
     assert str(Axis(annot=True, tick=True, grid=True)) == "afg"
     assert str(Axis(annot=30, tick=15, grid=5)) == "a30f15g5"
     assert str(Axis(annot=30, label="LABEL")) == "a30+lLABEL"
+    assert str(Axis(annot=30, prefix="$", unit="m")) == "a30+p$+um"
 
 
 def test_params_frame_only():

From 0ba431dba7b373d3702d97d78ef06952a6fc134b Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 21:56:57 +0800
Subject: [PATCH 07/23] Add doctest

---
 pygmt/params/frame.py | 51 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index 77b20699952..6e05266d869 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -13,6 +13,20 @@
 class Axis(BaseParam):
     """
     Class for setting up one axis of a plot.
+
+    Examples
+    --------
+    To specify the same attributes for all axes, with intervals of 4 for annotations,
+    2 for ticks, and 1 for gridlines:
+
+    >>> import pygmt
+    >>> fig = pygmmt.Figure()
+    >>> fig.basemap(
+    ...     region=[0, 10, 0, 20],
+    ...     projection="X10c/10c",
+    ...     frame=Axis(annot=4, tick=2, grid=1),
+    ... )
+    >>> fig.show()
     """
 
     #: Specify the interval for annoations. It can be ``True`` to let GMT decide the
@@ -72,6 +86,43 @@ def _aliases(self):
 class Frame(BaseParam):
     """
     Class for setting up the frame and axes of a plot.
+
+    Examples
+    --------
+    To specify the west and south axes with both tick marks and annotations, draw the
+    east and north axes with tick marks but without annotations:
+
+    >>> import pygmt
+    >>> fig = pygmt.Figure()
+    >>> fig.basemap(
+    ...     region=[0, 10, 0, 20], projection="X10c/10c", frame=Frame(axes="WSen")
+    ... )
+    >>> fig.show()
+
+    To specify the same attributes for all axes, with intervals of 4 for annotations,
+    2 for ticks, and 1 for gridlines:
+
+    >>> fig = pygmt.Figure()
+    >>> fig.basemap(
+    ...     region=[0, 10, 0, 20],
+    ...     projection="X10c/10c",
+    ...     frame=Frame(axes="WSrt", axis=Axis(annot=4, tick=2, grid=1)),
+    ... )
+    ... fig.show()
+
+    To specify the attributes for each axis separately:
+
+    >>> fig = pygmt.Figure()
+    >>> fig.basemap(
+    ...     region=[0, 10, 0, 20],
+    ...     projection="X10c/10c",
+    ...     frame=Frame(
+    ...         axes="WSrt",
+    ...         xaxis=Axis(annot=4, tick=2, grid=1, label="X-axis"),
+    ...         yaxis=Axis(annot=5, tick=2.5, grid=1, label="Y-axis"),
+    ...     ),
+    ... )
+    ... fig.show()
     """
 
     #: Controls which axes are drawn and whether they are annotated, using a combination

From b61639a448a58ed2df6af56001e2cd10c0619422 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 21:59:33 +0800
Subject: [PATCH 08/23] Add doctests

---
 pygmt/params/frame.py | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index 6e05266d869..e0ff162ec47 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -8,6 +8,8 @@
 from pygmt.exceptions import GMTParameterError
 from pygmt.params.base import BaseParam
 
+__doctest_skip__ = ["Axis", "Frame"]
+
 
 @dataclasses.dataclass(repr=False)
 class Axis(BaseParam):
@@ -20,7 +22,7 @@ class Axis(BaseParam):
     2 for ticks, and 1 for gridlines:
 
     >>> import pygmt
-    >>> fig = pygmmt.Figure()
+    >>> fig = pygmt.Figure()
     >>> fig.basemap(
     ...     region=[0, 10, 0, 20],
     ...     projection="X10c/10c",
@@ -108,7 +110,7 @@ class Frame(BaseParam):
     ...     projection="X10c/10c",
     ...     frame=Frame(axes="WSrt", axis=Axis(annot=4, tick=2, grid=1)),
     ... )
-    ... fig.show()
+    >>> fig.show()
 
     To specify the attributes for each axis separately:
 
@@ -118,11 +120,11 @@ class Frame(BaseParam):
     ...     projection="X10c/10c",
     ...     frame=Frame(
     ...         axes="WSrt",
-    ...         xaxis=Axis(annot=4, tick=2, grid=1, label="X-axis"),
-    ...         yaxis=Axis(annot=5, tick=2.5, grid=1, label="Y-axis"),
+    ...         xaxis=Axis(annot=4, tick=2, grid=1, label="X Label"),
+    ...         yaxis=Axis(annot=5, tick=2.5, grid=1, label="Y Label"),
     ...     ),
     ... )
-    ... fig.show()
+    >>> fig.show()
     """
 
     #: Controls which axes are drawn and whether they are annotated, using a combination

From 3a33364089416a4b84c1ef1f45729bc47b8a991f Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 22:05:28 +0800
Subject: [PATCH 09/23] Fix docstrings

---
 pygmt/params/frame.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index e0ff162ec47..514c2e518f5 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -33,7 +33,7 @@ class Axis(BaseParam):
 
     #: Specify the interval for annoations. It can be ``True`` to let GMT decide the
     #: interval automatically; or a value to set a specific interval in the format of
-    #: *stride*[±*phase*][*unit*], where, *stride* is the interval, *phase* is the
+    #: *stride*\ [±\ *phase*][*unit*], where, *stride* is the interval, *phase* is the
     #: offset to shift the annotations by that amount, and *unit* is one of the
     #: :gmt-docs:`18 supported unit codes <reference/options.html#tbl-units>` related to
     #: time intervals.

From c1dadd6379132ae6afea80b34328dd715e01cc89 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Thu, 12 Feb 2026 16:22:18 +0800
Subject: [PATCH 10/23] Fix an edge case

---
 pygmt/params/frame.py            | 5 ++++-
 pygmt/tests/test_params_frame.py | 6 ++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index 514c2e518f5..63344f601b2 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -203,8 +203,11 @@ def _validate(self):
 
     @property
     def _aliases(self):
+        # _Axes() maps to an empty string, which becomes '-B' without arguments and is
+        # invalid when combined with individual axis settings (e.g., '-B -Bxaf -Byaf').
+        frame_settings = _Axes(axes=self.axes, title=self.title)
         return [
-            Alias(_Axes(axes=self.axes, title=self.title)),
+            Alias(frame_settings) if str(frame_settings) else Alias(None),
             Alias(self.axis, name="axis"),
             Alias(self.xaxis, name="xaxis", prefix="px" if self.xaxis2 else "x"),
             Alias(self.yaxis, name="yaxis", prefix="py" if self.yaxis2 else "y"),
diff --git a/pygmt/tests/test_params_frame.py b/pygmt/tests/test_params_frame.py
index 55a5f58f36b..6b80e7854f1 100644
--- a/pygmt/tests/test_params_frame.py
+++ b/pygmt/tests/test_params_frame.py
@@ -43,6 +43,12 @@ def test_params_frame_separate_axes():
     """
     Test the Frame class with separate axis settings.
     """
+    frame = Frame(
+        xaxis=Axis(annot=10, tick=5, grid=2.5),
+        yaxis=Axis(annot=20, tick=10, grid=5),
+    )
+    assert list(frame) == ["xa10f5g2.5", "ya20f10g5"]
+
     frame = Frame(
         axes="lrtb",
         title="My Title",

From 2dde989a4903f1cda7b553b0a26451cd10f0f266 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Thu, 12 Feb 2026 17:20:06 +0800
Subject: [PATCH 11/23] Allow setting annotation angles

---
 pygmt/params/frame.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index 63344f601b2..8abade14dbe 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -55,6 +55,9 @@ class Axis(BaseParam):
     #: Unix to append to the axis annotations [For Cartesian plots only].
     unit: str | None = None
 
+    #: Angle of the axis annotations.
+    angle: float | None = None
+
     @property
     def _aliases(self):
         return [
@@ -62,6 +65,7 @@ def _aliases(self):
             Alias(self.tick, name="tick", prefix="f"),
             Alias(self.grid, name="grid", prefix="g"),
             Alias(self.label, name="label", prefix="+l"),
+            Alias(self.angle, name="angle", prefix="+a"),
             Alias(self.prefix, name="prefix", prefix="+p"),
             Alias(self.unit, name="unit", prefix="+u"),
         ]

From e990cbdba7b2e14e9a9f1b9fe28da5b9ebff936a Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Tue, 10 Feb 2026 23:53:19 +0800
Subject: [PATCH 12/23] Figure.colorbar: Pythonic way to set labels and
 annotations

---
 pygmt/src/colorbar.py | 101 +++++++++++++++++++++++++++++++++++++-----
 1 file changed, 89 insertions(+), 12 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index a52c8d9336f..588a45f43c4 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -11,12 +11,58 @@
 from pygmt.exceptions import GMTValueError
 from pygmt.helpers import build_arg_list, fmt_docstring, use_alias
 from pygmt.helpers.utils import is_nonstr_iter
-from pygmt.params import Box, Position
+from pygmt.params import Axis, Box, Frame, Position
 from pygmt.src._common import _parse_position
 
 __doctest_skip__ = ["colorbar"]
 
 
+def _build_frame(
+    annot: float | None = None,
+    tick: float | None = None,
+    grid: float | None = None,
+    annot_angel: float | None = None,
+    annot_prefix: str | None = None,
+    annot_unit: str | None = None,
+    label: str | None = None,
+    unit: str | None = None,
+    frame=None,
+):
+    """
+    Create the list of Alias objects for the -B option.
+
+    >>> _build_frame(annot=1, tick=0.5, xlabel="Distance", ylabel="Depth")
+    Frame(xaxis=Axis(annot=1, tick=0.5, label='Distance'), yaxis=Axis(label='Depth'))
+    """
+    if frame is not None and frame is not False:
+        return frame
+
+    _xaxis_is_set = any(
+        v is not None
+        for v in {annot, tick, grid, annot_angel, annot_prefix, annot_unit, label}
+    )
+    _yaxis_is_set = unit is not None
+
+    # Need to return None if no parameters are give. Otherwise, it may return "".
+    if not (_xaxis_is_set or _yaxis_is_set):
+        return None
+
+    xaxis, yaxis = None, None
+    if _xaxis_is_set:
+        xaxis = Axis(
+            annot=annot,
+            tick=tick,
+            grid=grid,
+            # angle=annot_angel,
+            # prefix=annot_prefix,
+            # unit=annot_unit,
+            label=label,
+        )
+    if _yaxis_is_set:
+        yaxis = Axis(label=unit)
+    return Frame(xaxis=xaxis, yaxis=yaxis)
+
+
 def _alias_option_D(  # noqa: N802, PLR0913
     position=None,
     length=None,
@@ -153,6 +199,15 @@ def colorbar(  # noqa: PLR0913
     length: float | str | None = None,
     width: float | str | None = None,
     orientation: Literal["horizontal", "vertical"] | None = None,
+    label: str | None = None,
+    unit: str | None = None,
+    annot: float | None = None,
+    tick: float | None = None,
+    grid: float | None = None,
+    annot_angel: float | None = None,
+    annot_prefix: str | None = None,
+    annot_unit: str | None = None,
+    frame: str | Sequence[str] | bool = False,
     reverse: bool = False,
     nan: bool = False,
     nan_position: Literal["start", "end"] | None = None,
@@ -168,7 +223,6 @@ def colorbar(  # noqa: PLR0913
     scale: float | None = None,
     projection: str | None = None,
     region: Sequence[float | str] | str | None = None,
-    frame: str | Sequence[str] | bool = False,
     verbose: Literal["quiet", "error", "warning", "timing", "info", "compat", "debug"]
     | bool = False,
     panel: int | Sequence[int] | bool = False,
@@ -201,7 +255,6 @@ def colorbar(  # noqa: PLR0913
     Full GMT docs at :gmt-docs:`colorbar.html`.
 
     $aliases
-       - B = frame
        - F = box
        - G = truncate
        - I = shading
@@ -217,6 +270,7 @@ def colorbar(  # noqa: PLR0913
     .. hlist::
        :columns: 1
 
+       - B = label, unit, annot, tick, grid, annot_angel, annot_prefix, annot_unit
        - D = position, **+w**: length/width, **+h**/**+v**: orientation,
          **+r**: reverse, **+n**: nan/nan_position,
          **+e**: fg_triangle/bg_triangle/triangle_height,
@@ -244,6 +298,26 @@ def colorbar(  # noqa: PLR0913
         given with unit ``%`` then it is in percentage of the bar length. [Length
         defaults to 80% of the corresponding plot side dimension, and width defaults
         to 4% of the bar length].
+    label
+    unit
+        Set the label and unit for the colorbar. The label is placed along the colorbar
+        and the unit is placed at the end of the colorbar.
+    annot
+    grid
+    tick
+        Intervals for annotations, grid lines, and ticks. Refer to
+        :class:`pygmt.params.Axis` for more details on how these parameters work.
+        Parameters ``annot_prefix``, ``annot_unit``, and ``annot_angel`` can be used to
+        further customize the annotations.
+    frame
+        Set colorbar boundary frame, labels, and axes attributes.
+
+        .. deprecated:: v0.19.0
+
+            Use ``annot``, ``tick``, ``grid``, ``annot_angel``, ``annot_prefix``,
+            ``annot_unit``, ``label``, and ``unit`` parameters to customize the colorbar
+            annotations and labels.
+
     orientation
         Set the colorbar orientation to either ``"horizontal"`` or ``"vertical"``.
         [Default is vertical, unless ``position`` is set to bottom-center or top-center
@@ -321,8 +395,6 @@ def colorbar(  # noqa: PLR0913
         requested colorbar length.
     $projection
     $region
-    frame
-        Set colorbar boundary frame, labels, and axes attributes.
     $verbose
     $panel
     $perspective
@@ -336,12 +408,7 @@ def colorbar(  # noqa: PLR0913
     >>> # Create a basemap
     >>> fig.basemap(region=[0, 10, 0, 3], projection="X10c/3c", frame=True)
     >>> # Call the colorbar method for the plot
-    >>> fig.colorbar(
-    ...     # Set cmap to the "roma" CPT
-    ...     cmap="SCM/roma",
-    ...     # Label the x-axis "Velocity" and the y-axis "m/s"
-    ...     frame=["x+lVelocity", "y+lm/s"],
-    ... )
+    >>> fig.colorbar(cmap="SCM/roma", label="Velocity", unit="m/s")
     >>> # Show the plot
     >>> fig.show()
     """
@@ -386,7 +453,17 @@ def colorbar(  # noqa: PLR0913
         Q=Alias(log, name="log"),
         W=Alias(scale, name="scale"),
     ).add_common(
-        B=frame,
+        B=_build_frame(
+            annot=annot,
+            tick=tick,
+            grid=grid,
+            annot_angel=annot_angel,
+            annot_prefix=annot_prefix,
+            annot_unit=annot_unit,
+            label=label,
+            unit=unit,
+            frame=frame,
+        ),
         J=projection,
         R=region,
         V=verbose,

From 3c75b9398554361de677442f6e537746b6dac6ba Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 11 Feb 2026 22:31:49 +0800
Subject: [PATCH 13/23] Fix doctest

---
 pygmt/src/colorbar.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index 588a45f43c4..ecb02e2cf3c 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -31,8 +31,8 @@ def _build_frame(
     """
     Create the list of Alias objects for the -B option.
 
-    >>> _build_frame(annot=1, tick=0.5, xlabel="Distance", ylabel="Depth")
-    Frame(xaxis=Axis(annot=1, tick=0.5, label='Distance'), yaxis=Axis(label='Depth'))
+    >>> list(_build_frame(annot=1, tick=0.5, label="Distance", unit="Depth"))
+    ['xa1f0.5+lDistance', 'y+lDepth']
     """
     if frame is not None and frame is not False:
         return frame

From c9461983782c922ca6866a9f97376f01c3ba5e54 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Thu, 12 Feb 2026 16:54:17 +0800
Subject: [PATCH 14/23] Fix typing issue

---
 pygmt/src/colorbar.py | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index ecb02e2cf3c..037bdefdca4 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -18,9 +18,9 @@
 
 
 def _build_frame(
-    annot: float | None = None,
-    tick: float | None = None,
-    grid: float | None = None,
+    annot: float | bool = False,
+    tick: float | bool = False,
+    grid: float | bool = False,
     annot_angel: float | None = None,
     annot_prefix: str | None = None,
     annot_unit: str | None = None,
@@ -201,9 +201,9 @@ def colorbar(  # noqa: PLR0913
     orientation: Literal["horizontal", "vertical"] | None = None,
     label: str | None = None,
     unit: str | None = None,
-    annot: float | None = None,
-    tick: float | None = None,
-    grid: float | None = None,
+    annot: float | bool = False,
+    tick: float | bool = False,
+    grid: float | bool = False,
     annot_angel: float | None = None,
     annot_prefix: str | None = None,
     annot_unit: str | None = None,

From de43548c37b3633d637bcd1294bd30ac117fbaa1 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Thu, 12 Feb 2026 16:59:14 +0800
Subject: [PATCH 15/23] Support angle/prefix/unit

---
 pygmt/src/colorbar.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index 037bdefdca4..a9dfe08bd6a 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -34,6 +34,7 @@ def _build_frame(
     >>> list(_build_frame(annot=1, tick=0.5, label="Distance", unit="Depth"))
     ['xa1f0.5+lDistance', 'y+lDepth']
     """
+    # Using the old 'frame' parameter.
     if frame is not None and frame is not False:
         return frame
 
@@ -53,9 +54,9 @@ def _build_frame(
             annot=annot,
             tick=tick,
             grid=grid,
-            # angle=annot_angel,
-            # prefix=annot_prefix,
-            # unit=annot_unit,
+            angle=annot_angel,
+            prefix=annot_prefix,
+            unit=annot_unit,
             label=label,
         )
     if _yaxis_is_set:

From 072fde2385b166d677d547e6d59148426c6afda9 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Thu, 12 Feb 2026 17:19:03 +0800
Subject: [PATCH 16/23] Fix a typo

---
 pygmt/src/colorbar.py | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index a9dfe08bd6a..2fdeb081482 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -21,7 +21,7 @@ def _build_frame(
     annot: float | bool = False,
     tick: float | bool = False,
     grid: float | bool = False,
-    annot_angel: float | None = None,
+    annot_angle: float | None = None,
     annot_prefix: str | None = None,
     annot_unit: str | None = None,
     label: str | None = None,
@@ -40,7 +40,7 @@ def _build_frame(
 
     _xaxis_is_set = any(
         v is not None
-        for v in {annot, tick, grid, annot_angel, annot_prefix, annot_unit, label}
+        for v in {annot, tick, grid, annot_angle, annot_prefix, annot_unit, label}
     )
     _yaxis_is_set = unit is not None
 
@@ -54,7 +54,7 @@ def _build_frame(
             annot=annot,
             tick=tick,
             grid=grid,
-            angle=annot_angel,
+            angle=annot_angle,
             prefix=annot_prefix,
             unit=annot_unit,
             label=label,
@@ -205,7 +205,7 @@ def colorbar(  # noqa: PLR0913
     annot: float | bool = False,
     tick: float | bool = False,
     grid: float | bool = False,
-    annot_angel: float | None = None,
+    annot_angle: float | None = None,
     annot_prefix: str | None = None,
     annot_unit: str | None = None,
     frame: str | Sequence[str] | bool = False,
@@ -271,7 +271,7 @@ def colorbar(  # noqa: PLR0913
     .. hlist::
        :columns: 1
 
-       - B = label, unit, annot, tick, grid, annot_angel, annot_prefix, annot_unit
+       - B = label, unit, annot, tick, grid, annot_angle, annot_prefix, annot_unit
        - D = position, **+w**: length/width, **+h**/**+v**: orientation,
          **+r**: reverse, **+n**: nan/nan_position,
          **+e**: fg_triangle/bg_triangle/triangle_height,
@@ -308,14 +308,14 @@ def colorbar(  # noqa: PLR0913
     tick
         Intervals for annotations, grid lines, and ticks. Refer to
         :class:`pygmt.params.Axis` for more details on how these parameters work.
-        Parameters ``annot_prefix``, ``annot_unit``, and ``annot_angel`` can be used to
+        Parameters ``annot_prefix``, ``annot_unit``, and ``annot_angle`` can be used to
         further customize the annotations.
     frame
         Set colorbar boundary frame, labels, and axes attributes.
 
         .. deprecated:: v0.19.0
 
-            Use ``annot``, ``tick``, ``grid``, ``annot_angel``, ``annot_prefix``,
+            Use ``annot``, ``tick``, ``grid``, ``annot_angle``, ``annot_prefix``,
             ``annot_unit``, ``label``, and ``unit`` parameters to customize the colorbar
             annotations and labels.
 
@@ -458,7 +458,7 @@ def colorbar(  # noqa: PLR0913
             annot=annot,
             tick=tick,
             grid=grid,
-            annot_angel=annot_angel,
+            annot_angle=annot_angle,
             annot_prefix=annot_prefix,
             annot_unit=annot_unit,
             label=label,

From 7aa50bd83e0970e81696367093f793343760310d Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Thu, 12 Feb 2026 17:19:16 +0800
Subject: [PATCH 17/23] Add more doctests

---
 pygmt/src/colorbar.py | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index 2fdeb081482..72915174718 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -31,8 +31,25 @@ def _build_frame(
     """
     Create the list of Alias objects for the -B option.
 
-    >>> list(_build_frame(annot=1, tick=0.5, label="Distance", unit="Depth"))
-    ['xa1f0.5+lDistance', 'y+lDepth']
+    >>> list(_build_frame(annot=1, tick=0.5, label="Distance", unit="km"))
+    ['xa1f0.5+lDistance', 'y+lkm']
+
+    >>> list(
+    ...     _build_frame(
+    ...         annot=1,
+    ...         tick=0.5,
+    ...         grid=0.2,
+    ...         annot_angel=30,
+    ...         annot_prefix="m",
+    ...         annot_unit="s",
+    ...         label="Distance",
+    ...         unit="km",
+    ...     )
+    ... )
+    ['xa1f0.5g0.2a30+m+s+lDistance', 'y+lkm']
+    >>> list(_build_frame(frame=["xaf0.5+lDistance", "y+lkm"])))
+    ['xaf0.5+lDistance', 'y+lkm']
+
     """
     # Using the old 'frame' parameter.
     if frame is not None and frame is not False:

From 13f13bfaa1a0352181346a5e0f5e4ac1cbe9da44 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Thu, 12 Feb 2026 18:33:01 +0800
Subject: [PATCH 18/23] Fix a typo in doctest

---
 pygmt/src/colorbar.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index 72915174718..de9f63e3c02 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -39,7 +39,7 @@ def _build_frame(
     ...         annot=1,
     ...         tick=0.5,
     ...         grid=0.2,
-    ...         annot_angel=30,
+    ...         annot_angle=30,
     ...         annot_prefix="m",
     ...         annot_unit="s",
     ...         label="Distance",

From b0037260f590c1804b16417c7a0e7f58e57f8de0 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Thu, 12 Feb 2026 22:08:59 +0800
Subject: [PATCH 19/23] Fix doctest

---
 pygmt/src/colorbar.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index de9f63e3c02..89d24f1094d 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -40,14 +40,12 @@ def _build_frame(
     ...         tick=0.5,
     ...         grid=0.2,
     ...         annot_angle=30,
-    ...         annot_prefix="m",
-    ...         annot_unit="s",
     ...         label="Distance",
     ...         unit="km",
     ...     )
     ... )
-    ['xa1f0.5g0.2a30+m+s+lDistance', 'y+lkm']
-    >>> list(_build_frame(frame=["xaf0.5+lDistance", "y+lkm"])))
+    ['xa1f0.5g0.2+lDistance+a30', 'y+lkm']
+    >>> list(_build_frame(frame=["xaf0.5+lDistance", "y+lkm"]))
     ['xaf0.5+lDistance', 'y+lkm']
 
     """

From 68261edea321c3527167de05db7289f2cec33524 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 25 Feb 2026 13:05:49 +0800
Subject: [PATCH 20/23] Fix a typo

---
 pygmt/params/frame.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pygmt/params/frame.py b/pygmt/params/frame.py
index 8abade14dbe..e1181ecb5e9 100644
--- a/pygmt/params/frame.py
+++ b/pygmt/params/frame.py
@@ -52,7 +52,7 @@ class Axis(BaseParam):
     #: related to money) [For Cartesian plots only].
     prefix: str | None = None
 
-    #: Unix to append to the axis annotations [For Cartesian plots only].
+    #: Unit to append to the axis annotations [For Cartesian plots only].
     unit: str | None = None
 
     #: Angle of the axis annotations.

From 3f94e419509828319a99ff859a207b5646735970 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 25 Feb 2026 13:09:37 +0800
Subject: [PATCH 21/23] Fix merge conflicts

---
 pygmt/src/colorbar.py | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index 7fd1ed2bb4b..18439100600 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -326,7 +326,8 @@ def colorbar(  # noqa: PLR0913
         Parameters ``annot_prefix``, ``annot_unit``, and ``annot_angle`` can be used to
         further customize the annotations.
     frame
-        Set colorbar boundary frame, labels, and axes attributes.
+        Set colorbar boundary frame, labels, and axes attributes. If set to ``"none"``,
+        then no frame will be drawn.
 
         .. deprecated:: v0.19.0
 
@@ -411,12 +412,6 @@ def colorbar(  # noqa: PLR0913
         requested colorbar length.
     $projection
     $region
-    <<<<<<< HEAD
-    =======
-    frame
-        Set colorbar boundary frame, labels, and axes attributes. If set to ``"none"``,
-        then no frame will be drawn.
-    >>>>>>> class/frame-part1
     $verbose
     $panel
     $perspective

From 5498316f36b4aa2a1159a659f08679fbee384c51 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Wed, 25 Feb 2026 14:30:56 +0800
Subject: [PATCH 22/23] Allow frame='none' in colorbar

---
 pygmt/src/colorbar.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index 18439100600..b84d81fa890 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -48,13 +48,16 @@ def _build_frame(
     >>> list(_build_frame(frame=["xaf0.5+lDistance", "y+lkm"]))
     ['xaf0.5+lDistance', 'y+lkm']
 
+    >>> _build_frame(frame="none")
+    'none'
+    >>> _build_frame()  # Passing no parameters returns None
     """
     # Using the old 'frame' parameter.
     if frame is not None and frame is not False:
         return frame
 
     _xaxis_is_set = any(
-        v is not None
+        v is not None and v is not False
         for v in {annot, tick, grid, annot_angle, annot_prefix, annot_unit, label}
     )
     _yaxis_is_set = unit is not None

From e30070ffbba545a427102be2c6f0680dfa3d4b45 Mon Sep 17 00:00:00 2001
From: Dongdong Tian <seisman.info@gmail.com>
Date: Mon, 9 Mar 2026 10:40:08 +0800
Subject: [PATCH 23/23] Improve docstrings

---
 pygmt/src/colorbar.py | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/pygmt/src/colorbar.py b/pygmt/src/colorbar.py
index b84d81fa890..89a3e2d0d40 100644
--- a/pygmt/src/colorbar.py
+++ b/pygmt/src/colorbar.py
@@ -322,22 +322,19 @@ def colorbar(  # noqa: PLR0913
         Set the label and unit for the colorbar. The label is placed along the colorbar
         and the unit is placed at the end of the colorbar.
     annot
-    grid
     tick
-        Intervals for annotations, grid lines, and ticks. Refer to
+    grid
+        Intervals for annotations, ticks, and gridlines. Refer to
         :class:`pygmt.params.Axis` for more details on how these parameters work.
-        Parameters ``annot_prefix``, ``annot_unit``, and ``annot_angle`` can be used to
-        further customize the annotations.
+    annot_prefix
+    annot_unit
+    annot_angle
+        The prefix, unit and angle for the annotations. The prefix is placed before the
+        annotation text; the unit is placed after the annotation text; and the angle is
+        the angle of the annotation text.
     frame
         Set colorbar boundary frame, labels, and axes attributes. If set to ``"none"``,
         then no frame will be drawn.
-
-        .. deprecated:: v0.19.0
-
-            Use ``annot``, ``tick``, ``grid``, ``annot_angle``, ``annot_prefix``,
-            ``annot_unit``, ``label``, and ``unit`` parameters to customize the colorbar
-            annotations and labels.
-
     orientation
         Set the colorbar orientation to either ``"horizontal"`` or ``"vertical"``.
         [Default is vertical, unless ``position`` is set to bottom-center or top-center