Add docstrings and tests to gmtinfo

gmt/modules.py

@@ -10,12 +10,32 @@ def info(fname, **kwargs):
     """
     Get information about data tables.
 
+    Reads from files and finds the extreme values in each of the columns.
+    It recognizes NaNs and will print warnings if the number of columns vary
+    from record to record. As an option, it will find the extent of the first
+    n columns rounded up and down to the nearest multiple of the supplied
+    increments. By default, this output will be in the form *-Rw/e/s/n*,
+    or the output will be in column form for as many columns as there are
+    increments provided. The *T* option will provide a *-Tzmin/zmax/dz* string
+    for makecpt.
+
     {gmt_module_docs}
 
     Parameters
     ----------
     fname : str
         The file name of the input data table file.
+    C : bool
+        Report the min/max values per column in separate columns.
+    I : str
+        ``'[b|p|f|s]dx[/dy[/dz...]]'``.
+        Report the min/max of the first n columns to the nearest multiple of
+        the provided increments and output results in the form *-Rw/e/s/n*
+        (unless *C* is set).
+    T : str
+        ``'dz[+ccol]'``
+        Report the min/max of the first (0'th) column to the nearest multiple
+        of dz and output this as the string *-Tzmin/zmax/dz*.
     """
     assert isinstance(fname, str), 'Only accepts file names.'
 

gmt/tests/test_info.py

@@ -0,0 +1,44 @@
+"""
+Tests for gmtinfo
+"""
+import os
+
+from .. import info
+
+TEST_DATA_DIR = os.path.join(os.path.dirname(__file__), 'data')
+POINTS_DATA = os.path.join(TEST_DATA_DIR, 'points.txt')
+
+
+def test_info():
+    "Make sure info works"
+    output = info(fname=POINTS_DATA)
+    expected_output = ('{}: N = 20 '
+                       '<11.5309/61.7074> '
+                       '<-2.9289/7.8648> '
+                       '<0.1412/0.9338>\n').format(POINTS_DATA)
+
+    assert output == expected_output
+
+
+def test_info_c():
+    "Make sure the C option works"
+    output = info(fname=POINTS_DATA, C=True)
+    assert output == '11.5309 61.7074 -2.9289 7.8648 0.1412 0.9338\n'
+
+
+def test_info_i():
+    "Make sure the I option works"
+    output = info(fname=POINTS_DATA, I=0.1)
+    assert output == '-R11.5/61.8/-3/7.9\n'
+
+
+def test_info_c_i():
+    "Make sure the C and I options work together"
+    output = info(fname=POINTS_DATA, C=True, I=0.1)
+    assert output == '11.5 61.8 -3 7.9 0.1412 0.9338\n'
+
+
+def test_info_t():
+    "Make sure the T option works"
+    output = info(fname=POINTS_DATA, T=0.1)
+    assert output == '-T11.5/61.8/0.1\n'