Make the size of a heatmap bigger with seaborn
I create a heatmap with seaborn
df1.index = pd.to_datetime(df1.index)
df1 = df1.set_index('TIMESTAMP')
df1 = df1.resample('30min').mean()
ax = sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5)
But the probleme is when there is lot of data in the dataframe the heatmap will be too small and the value inside begin not clear like in the attached image.
How can I change the size of the heatmap to be more bigger ?
Thank you
EDIT
I try :
df1.index = pd.to_datetime(df1.index)
fig, ax = plt.subplots(figsize=(10,10)) # Sample figsize in inches
sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5, ax=ax)
df1 = df1.set_index('TIMESTAMP')
df1 = df1.resample('1d').mean()
ax = sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5)
But I get this error :
KeyError Traceback (most recent call last)
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\indexes\base.py in get_loc(self, key, method, tolerance)
1944 try:
-> 1945 return self._engine.get_loc(key)
1946 except KeyError:
pandas\index.pyx in pandas.index.IndexEngine.get_loc (pandas\index.c:4154)()
pandas\index.pyx in pandas.index.IndexEngine.get_loc (pandas\index.c:4018)()
pandas\hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas\hashtable.c:12368)()
pandas\hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas\hashtable.c:12322)()
KeyError: 'TIMESTAMP'
During handling of the above exception, another exception occurred:
KeyError Traceback (most recent call last)
<ipython-input-779-acaf05718dd8> in <module>()
2 fig, ax = plt.subplots(figsize=(10,10)) # Sample figsize in inches
3 sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5, ax=ax)
----> 4 df1 = df1.set_index('TIMESTAMP')
5 df1 = df1.resample('1d').mean()
6 ax = sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5)
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.py in set_index(self, keys, drop, append, inplace, verify_integrity)
2835 names.append(None)
2836 else:
-> 2837 level = frame[col]._values
2838 names.append(col)
2839 if drop:
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.py in __getitem__(self, key)
1995 return self._getitem_multilevel(key)
1996 else:
-> 1997 return self._getitem_column(key)
1998
1999 def _getitem_column(self, key):
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\frame.py in _getitem_column(self, key)
2002 # get column
2003 if self.columns.is_unique:
-> 2004 return self._get_item_cache(key)
2005
2006 # duplicate columns & possible reduce dimensionality
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\generic.py in _get_item_cache(self, item)
1348 res = cache.get(item)
1349 if res is None:
-> 1350 values = self._data.get(item)
1351 res = self._box_item_values(item, values)
1352 cache[item] = res
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\core\internals.py in get(self, item, fastpath)
3288
3289 if not isnull(item):
-> 3290 loc = self.items.get_loc(item)
3291 else:
3292 indexer = np.arange(len(self.items))[isnull(self.items)]
C:\Users\Demonstrator\Anaconda3\lib\site-packages\pandas\indexes\base.py in get_loc(self, key, method, tolerance)
1945 return self._engine.get_loc(key)
1946 except KeyError:
-> 1947 return self._engine.get_loc(self._maybe_cast_indexer(key))
1948
1949 indexer = self.get_indexer([key], method=method, tolerance=tolerance)
pandas\index.pyx in pandas.index.IndexEngine.get_loc (pandas\index.c:4154)()
pandas\index.pyx in pandas.index.IndexEngine.get_loc (pandas\index.c:4018)()
pandas\hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas\hashtable.c:12368)()
pandas\hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas\hashtable.c:12322)()
KeyError: 'TIMESTAMP'
EDIT
TypeError Traceback (most recent call last)
<ipython-input-890-86bff697504a> in <module>()
2 df2.resample('30min').mean()
3 fig, ax = plt.subplots()
----> 4 ax = sns.heatmap(df2.iloc[:, 1:6:], annot=True, linewidths=.5)
5 ax.set_yticklabels([i.strftime("%Y-%m-%d %H:%M:%S") for i in df2.index], rotation=0)
C:\Users\Demonstrator\Anaconda3\lib\site-packages\seaborn\matrix.py in heatmap(data, vmin, vmax, cmap, center, robust, annot, fmt, annot_kws, linewidths, linecolor, cbar, cbar_kws, cbar_ax, square, ax, xticklabels, yticklabels, mask, **kwargs)
483 plotter = _HeatMapper(data, vmin, vmax, cmap, center, robust, annot, fmt,
484 annot_kws, cbar, cbar_kws, xticklabels,
--> 485 yticklabels, mask)
486
487 # Add the pcolormesh kwargs here
C:\Users\Demonstrator\Anaconda3\lib\site-packages\seaborn\matrix.py in __init__(self, data, vmin, vmax, cmap, center, robust, annot, fmt, annot_kws, cbar, cbar_kws, xticklabels, yticklabels, mask)
165 # Determine good default values for the colormapping
166 self._determine_cmap_params(plot_data, vmin, vmax,
--> 167 cmap, center, robust)
168
169 # Sort out the annotations
C:\Users\Demonstrator\Anaconda3\lib\site-packages\seaborn\matrix.py in _determine_cmap_params(self, plot_data, vmin, vmax, cmap, center, robust)
202 cmap, center, robust):
203 """Use some heuristics to set good defaults for colorbar and range."""
--> 204 calc_data = plot_data.data[~np.isnan(plot_data.data)]
205 if vmin is None:
206 vmin = np.percentile(calc_data, 2) if robust else calc_data.min()
TypeError: ufunc 'isnan' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe''
Solution 1:
You could alter the figsize by passing a tuple showing the width, height parameters you would like to keep.
import matplotlib.pyplot as plt
fig, ax = plt.subplots(figsize=(10,10)) # Sample figsize in inches
sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5, ax=ax)
EDIT
I remember answering a similar question of yours where you had to set the index as TIMESTAMP. So, you could then do something like below:
df = df.set_index('TIMESTAMP')
df.resample('30min').mean()
fig, ax = plt.subplots()
ax = sns.heatmap(df.iloc[:, 1:6:], annot=True, linewidths=.5)
ax.set_yticklabels([i.strftime("%Y-%m-%d %H:%M:%S") for i in df.index], rotation=0)
For the head of the dataframe you posted, the plot would look like:
Solution 2:
add plt.figure(figsize=(16,5)) before the sns.heatmap and play around with the figsize numbers till you get the desired size
...
plt.figure(figsize = (16,5))
ax = sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5)
Solution 3:
I do not know how to solve this using code, but I do manually adjust the control panel at the right bottom in the plot figure, and adjust the figure size like:
f, ax = plt.subplots(figsize=(16, 12))
at the meantime until you get a matched size colobar. This worked for me.