adapt histograms to float/int (#2247)

* adapt histograms to float/int

* changelog and black

* fix logic in bokeh

* define ticks from bin edges after calling hist

* black

CHANGELOG.md

@@ -9,6 +9,7 @@
 ### Maintenance and fixes
 
 - Fixes for creating numpy object array ([2233](https://github.com/arviz-devs/arviz/pull/2233) and [2239](https://github.com/arviz-devs/arviz/pull/2239))
+- Adapt histograms generated by plot_dist to input dtype ([2247](https://github.com/arviz-devs/arviz/pull/2247))
 
 ### Deprecation
 

arviz/plots/backends/bokeh/distplot.py

@@ -141,6 +141,8 @@ def _histplot_bokeh_op(values, values2, rotated, ax, hist_kwargs, is_circular):
     if hist_kwargs.pop("cumulative", False):
         hist = np.cumsum(hist)
         hist /= hist[-1]
+    if values.dtype.kind == "i":
+        edges = edges.astype(float) - 0.5
 
     if is_circular:
 
@@ -174,7 +176,6 @@ def _histplot_bokeh_op(values, values2, rotated, ax, hist_kwargs, is_circular):
         )
 
         ax = set_bokeh_circular_ticks_labels(ax, hist, labels)
-
     elif rotated:
         ax.quad(top=edges[:-1], bottom=edges[1:], left=0, right=hist, **hist_kwargs)
     else:

arviz/plots/backends/matplotlib/distplot.py

@@ -67,7 +67,6 @@ def plot_dist(
         hist_kwargs.setdefault("color", color)
         hist_kwargs.setdefault("label", label)
         hist_kwargs.setdefault("rwidth", 0.9)
-        hist_kwargs.setdefault("align", "left")
         hist_kwargs.setdefault("density", True)
 
         if rotated:
@@ -151,12 +150,22 @@ def _histplot_mpl_op(values, values2, rotated, ax, hist_kwargs, is_circular):
     if bins is None:
         bins = get_bins(values)
 
+    if values.dtype.kind == "i":
+        hist_kwargs.setdefault("align", "left")
+    else:
+        hist_kwargs.setdefault("align", "mid")
+
     n, bins, _ = ax.hist(np.asarray(values).flatten(), bins=bins, **hist_kwargs)
 
+    if values.dtype.kind == "i":
+        ticks = bins[:-1]
+    else:
+        ticks = (bins[1:] + bins[:-1]) / 2
+
     if rotated:
-        ax.set_yticks(bins[:-1])
+        ax.set_yticks(ticks)
     elif not is_circular:
-        ax.set_xticks(bins[:-1])
+        ax.set_xticks(ticks)
 
     if is_circular:
         ax.set_ylim(0, 1.5 * n.max())