Fix "pandas.Dataframe" to "pandas.DataFrame" in pygmt/datasets/sample…

…s.py (GenericMappingTools#1124)

Co-authored-by: Dongdong Tian <[email protected]>

pygmt/datasets/samples.py

@@ -7,7 +7,7 @@
 
 def load_japan_quakes():
  """
- Load a table of earthquakes around Japan as a pandas.Dataframe.
+ Load a table of earthquakes around Japan as a pandas.DataFrame.
 
  Data is from the NOAA NGDC database. This is the ``@tut_quakes.ngdc``
  dataset used in the GMT tutorials.
@@ -18,7 +18,7 @@ def load_japan_quakes():
 
  Returns
  -------
- data :  pandas.Dataframe
+ data : pandas.DataFrame
  The data table. Columns are year, month, day, latitude, longitude,
  depth (in km), and magnitude of the earthquakes.
  """
@@ -49,7 +49,7 @@ def load_ocean_ridge_points():
 
  Returns
  -------
- data :  pandas.Dataframe
+ data : pandas.DataFrame
  The data table. Columns are longitude and latitude.
  """
  fname = which("@ridge.txt", download="c")
@@ -72,7 +72,7 @@ def load_sample_bathymetry():
 
  Returns
  -------
- data :  pandas.Dataframe
+ data : pandas.DataFrame
  The data table. Columns are longitude, latitude, and bathymetry.
  """
  fname = which("@tut_ship.xyz", download="c")
@@ -84,7 +84,7 @@ def load_sample_bathymetry():
 
 def load_usgs_quakes():
  """
- Load a table of global earthquakes form the USGS as a pandas.Dataframe.
+ Load a table of global earthquakes form the USGS as a pandas.DataFrame.
 
  This is the ``@usgs_quakes_22.txt`` dataset used in the GMT tutorials.
 
@@ -94,7 +94,7 @@ def load_usgs_quakes():
 
  Returns
  -------
- data : pandas.Dataframe
+ data : pandas.DataFrame
  The data table. Use ``print(data.describe())`` to see the available
  columns.
  """