add iplt.text (#246)

* init text

* `eval_xy` caching and param excluding

* text docstring

* text docs

* fix param excluder when None passed

* fix linking

Author: ianhi

docs/examples/text-annotations.ipynb

@@ -0,0 +1,172 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "ddddb250-faff-496c-8f0e-6935196ec14a",
+   "metadata": {},
+   "source": [
+    "# Text and Annotations\n",
+    "\n",
+    "\n",
+    "```{note}\n",
+    "Support for modifying text is not complete as none of the function implemented support updating `fontdict` or other text properties like size and color. However, the core functionality is there to place text, change it's position, or change what it reads. see https://github.com/ianhi/mpl-interactions/issues/247 for updates.\n",
+    "```"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "ec2f6996-5f39-4009-a94d-e3a3fda108d9",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "%matplotlib ipympl\n",
+    "import matplotlib.pyplot as plt\n",
+    "import numpy as np\n",
+    "\n",
+    "from mpl_interactions import ipyplot as iplt"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "692989d9-07f1-4969-81d8-fc330f0aa5d4",
+   "metadata": {},
+   "source": [
+    "## Working with text strings.\n",
+    "\n",
+    "There are two ways to dynamically update text strings in mpl-interactions.\n",
+    "1. Use a function to return a string\n",
+    "2. Use a named string formatting\n",
+    "\n",
+    "\n",
+    "You can also combine these and have your function return a string that then gets formatted.\n",
+    "\n",
+    "\n",
+    "In the example below the `xlabel` is generated using a function and the `title` is generated using the formatting approach."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "d97390af-872e-42f5-a939-03b734b1cf4f",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "fig, ax = plt.subplots()\n",
+    "\n",
+    "x = np.linspace(0, np.pi, 100)\n",
+    "\n",
+    "\n",
+    "def y(x, volts, tau):\n",
+    "    return np.sin(x * tau) * volts\n",
+    "\n",
+    "\n",
+    "ctrls = iplt.plot(x, y, volts=(0.5, 10), tau=(1, 10, 100))\n",
+    "\n",
+    "\n",
+    "def xlabel_func(tau):\n",
+    "    # you can do arbitrary python here to make a more\n",
+    "    # complicated string\n",
+    "    return f\"Time with a max tau of {np.round(tau, 3)}\"\n",
+    "\n",
+    "\n",
+    "with ctrls[\"tau\"]:\n",
+    "    iplt.xlabel(xlabel_func)\n",
+    "with ctrls:\n",
+    "    # directly using string formatting\n",
+    "    # the formatting is performed in the update\n",
+    "    iplt.title(title=\"The voltage is {volts:.2f}\")"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "1e152d5d-6c6f-4e87-b5d6-f6755f4bed17",
+   "metadata": {},
+   "source": [
+    "## Arbitrarily placed text\n",
+    "\n",
+    "For this you can use {func}`.interactive_text`. Currently `plt.annotation` is not supported. \n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "1ccdd8c4-91fa-440a-9a2d-dbea694ee92d",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "fig, ax = plt.subplots()\n",
+    "\n",
+    "theta = np.linspace(0, 2 * np.pi, 100)\n",
+    "\n",
+    "\n",
+    "def gen_string(theta):\n",
+    "    return f\"angle = {np.round(np.rad2deg(theta))}\"\n",
+    "\n",
+    "\n",
+    "def fx(theta):\n",
+    "    return np.cos(theta)\n",
+    "\n",
+    "\n",
+    "def fy(x, theta):\n",
+    "    return np.sin(theta)\n",
+    "\n",
+    "\n",
+    "ctrls = iplt.text(fx, fy, gen_string, theta=theta)\n",
+    "ax.set_xlim([-1.25, 1.25])\n",
+    "_ = ax.set_ylim([-1.25, 1.25])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "e2aafbc0-7958-410e-a3b8-ce0a8a75ef30",
+   "metadata": {
+    "jp-MarkdownHeadingCollapsed": true,
+    "tags": []
+   },
+   "source": [
+    "Since the `x` and `y` positions are scalars you can also do nifty things like directly define them by a slider shorthand in the function.\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "8eb7da4d-3e48-4b28-85a8-080ff85eee0d",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "fig, ax = plt.subplots()\n",
+    "ctrls = iplt.text((0, 1, 100), (0.25, 1, 100), \"{x:.2f}, {y:.2f}\")"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.9.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

docs/index.md

@@ -101,6 +101,7 @@ examples/custom-callbacks.ipynb
 examples/animations.ipynb
 examples/range-sliders.ipynb
 examples/scalar-arguments.ipynb
+examples/text-annotations.ipynb
 examples/tidbits.md
 ```
 

mpl_interactions/controller.py

@@ -467,9 +467,12 @@ def excluder(params, except_=None):
         Parameters
         ----------
         params : dict
-        except : str
+        except : str or list[str]
         """
-        return {k: v for k, v in params.items() if k not in added_kwargs or k == except_}
+        if isinstance(except_, str) or except_ is None:
+            except_ = [except_]
+
+        return {k: v for k, v in params.items() if k not in added_kwargs or k in except_}
 
     return excluder
 

mpl_interactions/helpers.py

@@ -238,29 +238,38 @@ def f(params):
 def eval_xy(x_, y_, params, cache=None):
     """
     for when y requires x as an argument and either, neither or both
-    of x and y may be a function.
+    of x and y may be a function. This will automatically do the param exclusion
+    for 'x' and 'y'.
 
     Returns
     -------
     x, y
         as numpy arrays
     """
-    if isinstance(x_, Callable):
+    if "x" in params:
+        # passed as a scalar with a slider
+        x = params["x"]
+    elif isinstance(x_, Callable):
         if cache is not None:
             if x_ in cache:
                 x = cache[x_]
             else:
                 x = x_(**params)
+                cache[x_] = x
         else:
             x = x_(**params)
     else:
         x = x_
-    if isinstance(y_, Callable):
+    if "y" in params:
+        # passed a scalar with a slider
+        y = params["y"]
+    elif isinstance(y_, Callable):
         if cache is not None:
             if y_ in cache:
                 y = cache[y_]
             else:
                 y = y_(x, **params)
+                cache[y_] = y
         else:
             y = y_(x, **params)
     else:

mpl_interactions/ipyplot.py

@@ -4,6 +4,7 @@
 from .pyplot import interactive_imshow as imshow
 from .pyplot import interactive_plot as plot
 from .pyplot import interactive_scatter as scatter
+from .pyplot import interactive_text as text
 from .pyplot import interactive_title as title
 from .pyplot import interactive_xlabel as xlabel
 from .pyplot import interactive_ylabel as ylabel

mpl_interactions/pyplot.py

@@ -42,6 +42,7 @@
     "interactive_title",
     "interactive_xlabel",
     "interactive_ylabel",
+    "interactive_text",
 ]
 
 
@@ -1247,3 +1248,92 @@ def update(params, indices, cache):
         **text_kwargs,
     )
     return controls
+
+
+def interactive_text(
+    x,
+    y,
+    s,
+    fontdict=None,
+    controls=None,
+    ax=None,
+    *,
+    slider_formats=None,
+    display_controls=True,
+    play_buttons=False,
+    force_ipywidgets=False,
+    **kwargs,
+):
+    """
+    Create a text object that will update interactively.
+    kwargs for `matplotlib.text.Text` will be passed through, other kwargs will be used to create interactive controls.
+
+    .. note::
+
+        fontdict properties are currently static - see https://github.com/ianhi/mpl-interactions/issues/247
+
+
+    Parameters
+    ----------
+    x, y : float or function
+        The text position.
+    s : str or function
+        The text. Can either be static text, a function returning a string or
+        can include {} style formatting. e.g. 'The voltage is {volts:.2f}'
+    fontdict : dict[str]
+        Passed through to the Text object. Currently not dynamically updateable. See
+        https://github.com/ianhi/mpl-interactions/issues/247
+    controls : mpl_interactions.controller.Controls
+        An existing controls object if you want to tie multiple plot elements to the same set of
+        controls
+    ax : matplotlib axis, optional
+        The axis on which to plot. If none the current axis will be used.
+    play_buttons : bool or str or dict, optional
+        Whether to attach an ipywidgets.Play widget to any sliders that get created.
+        If a boolean it will apply to all kwargs, if a dictionary you choose which sliders you
+        want to attach play buttons too.
+
+        - None: no sliders
+        - True: sliders on the lft
+        - False: no sliders
+        - 'left': sliders on the left
+        - 'right': sliders on the right
+
+    force_ipywidgets : boolean
+        If True ipywidgets will always be used, even if not using the ipympl backend.
+        If False the function will try to detect if it is ok to use ipywidgets
+        If ipywidgets are not used the function will fall back on matplotlib widgets
+
+    Returns
+    -------
+    controls
+    """
+    ipympl = notebook_backend()
+    fig, ax = gogogo_figure(ipympl, ax)
+    ipympl or force_ipywidgets
+    slider_formats = create_slider_format_dict(slider_formats)
+
+    kwargs, text_kwargs = kwarg_popper(kwargs, Text_kwargs_list)
+    funcs, extra_ctrls, param_excluder = prep_scalars(kwargs, x=x, y=y)
+    x = funcs["x"]
+    y = funcs["y"]
+    controls, params = gogogo_controls(
+        kwargs, controls, display_controls, slider_formats, play_buttons, extra_ctrls
+    )
+
+    def update(params, indices, cache):
+        x_, y_ = eval_xy(x, y, param_excluder(params, ["x", "y"]), cache)
+        text.set_x(x_)
+        text.set_y(y_)
+        text.set_text(callable_else_value_no_cast(s, params, cache).format(**params))
+
+    controls._register_function(update, fig, params)
+    x_, y_ = eval_xy(x, y, param_excluder(params, ["x", "y"]))
+    text = ax.text(
+        x_,
+        y_,
+        callable_else_value_no_cast(s, params).format(**params),
+        fontdict=fontdict,
+        **text_kwargs,
+    )
+    return controls