Custom Formatting for Seaborn Annotations

remove_leading_zeros_heatmap.py

## Because Seaborn doesn't allow custom formatting for annotations, you have to do this crazy workaround to access the text:

def formatFloat(fmt, val):
  ret = fmt % val
  if ret.startswith("0."):
    return ret[1:]
  if ret.startswith("-0."):
    return "-" + ret[2:]
  return ret

ax = sns.heatmap(df_to_plot, vmin=-1, vmax=1, annot=True, cmap='seismic', square=True)#, fmt='.1g')# lambda x: formatFloat('%.2f', x))

texts = list(ax.texts)
for t in texts:
    t.set_visible(False)

for t in texts:
    text = t.get_text()
    s = formatFloat('%.1f', float(text))
    x = t._x
    y = t._y
    c = t._color
    ax.text(x, y, s, color=c, ha="center", va="center")