Bug fix: Use np.isclose for float equality in number line elongated ticks (#3392)

* use np.isclose for float equality in number line elongated ticks

* use offsets relative to x_min to tell if we need to elongate a tick

* forgot to subtract to create list of offsets

* add test for elongated ticks float equality

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Remove unused import

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: hari387

manim/mobject/graphing/number_line.py

@@ -277,9 +277,10 @@ def add_ticks(self):
         via ``self.ticks``."""
         ticks = VGroup()
         elongated_tick_size = self.tick_size * self.longer_tick_multiple
+        elongated_tick_offsets = self.numbers_with_elongated_ticks - self.x_min
         for x in self.get_tick_range():
             size = self.tick_size
-            if x in self.numbers_with_elongated_ticks:
+            if np.any(np.isclose(x - self.x_min, elongated_tick_offsets)):
                 size = elongated_tick_size
             ticks.add(self.get_tick(x, size))
         self.add(ticks)

tests/module/mobject/graphing/test_ticks.py

@@ -13,6 +13,27 @@ def test_duplicate_ticks_removed_for_axes():
     assert np.unique(ticks).size == ticks.size
 
 
+def test_elongated_ticks_float_equality():
+    nline = NumberLine(
+        x_range=[1 + 1e-5, 1 + 2e-5, 1e-6],
+        numbers_with_elongated_ticks=[
+            1 + 12e-6,
+            1 + 17e-6,
+        ],  # Elongate the 3rd and 8th tick
+        include_ticks=True,
+    )
+
+    tick_heights = {tick.height for tick in nline.ticks}
+    default_tick_height, elongated_tick_height = min(tick_heights), max(tick_heights)
+
+    assert all(
+        tick.height == elongated_tick_height
+        if ind in [2, 7]
+        else tick.height == default_tick_height
+        for ind, tick in enumerate(nline.ticks)
+    )
+
+
 def test_ticks_not_generated_on_origin_for_axes():
     axes = Axes(
         x_range=[-10, 10],