i.pca: added tests for the module (#3550)

* Add test_pca.py

* Add assertRasterFitsInfo assertion

* Add tests for r.univar results [i.pca] & save expected results in files

* i.pca: clear maps after testing is done

* Add header to test_pca.py

* remove data directory and save results in script

* Update imagery/i.pca/testsuite/test_pca.py

---------

Co-authored-by: Stefan Blumentrath <stefan.blumentrath@gmx.de>

imagery/i.pca/testsuite/test_pca.py

@@ -0,0 +1,174 @@
+"""
+Name:       i.pca test
+Purpose:    Tests i.pca.
+
+Author:     Hamed Elgizery - hamedashraf2004@gmail.com
+Copyright:  (C) 2024 by Hamed Elgizery and the GRASS Development Team
+Licence:    This program is free software under the GNU General Public
+                License (>=v2). Read the file COPYING that comes with GRASS
+                for details.
+"""
+from grass.gunittest.case import TestCase
+
+
+class TestReport(TestCase):
+    @classmethod
+    def setUpClass(cls):
+        """Use temporary region settings"""
+        cls.runModule("g.region", raster="lsat7_2002_10@PERMANENT")
+        cls.use_temp_region()
+
+    @classmethod
+    def tearDownClass(cls):
+        cls.runModule(
+            "g.remove",
+            flags="f",
+            type="raster",
+            name="lsat7_2002_pca.1,lsat7_2002_pca.2,lsat7_2002_pca.3,lsat7_2002_pca.4,lsat7_2002_pca.6",
+        )
+        cls.del_temp_region()
+
+    def test_pca_sample(self):
+        """Testing pca sample"""
+        self.assertModule(
+            "i.pca",
+            input="lsat7_2002_10,lsat7_2002_20,lsat7_2002_30,lsat7_2002_40,lsat7_2002_50,lsat7_2002_70",
+            output="lsat7_2002_pca",
+        )
+
+        lsat7_2002_pca_info_out = """north=228513
+            south=214975.5
+            east=645012
+            west=629992.5
+            nsres=28.5
+            ewres=28.5
+            rows=475
+            cols=527
+            cells=250325
+            datatype=CELL
+            ncats=0
+            comments=\"Eigen values, (vectors), and [percent importance]:PC1   4334.35 ( 0.2824, 0.3342, 0.5092,-0.0087, 0.5264, 0.5217) [83.04%]PC2    588.31 ( 0.2541, 0.1885, 0.2923,-0.7428,-0.5110,-0.0403) [11.27%]PC3    239.22 ( 0.3801, 0.3819, 0.2681, 0.6238,-0.4000,-0.2980) [ 4.58%]PC4     32.85 ( 0.1752,-0.0191,-0.4053, 0.1593,-0.4435, 0.7632) [ 0.63%]PC5     20.73 (-0.6170,-0.2514, 0.6059, 0.1734,-0.3235, 0.2330) [ 0.40%]PC6      4.08 (-0.5475, 0.8021,-0.2282,-0.0607,-0.0208, 0.0252) [ 0.08%]i.pca input=\"lsat7_2002_10,lsat7_2002_20,lsat7_2002_30,lsat7_2002_40\,lsat7_2002_50,lsat7_2002_70\" output=\"lsat7_2002_pca\" rescale=0,255 \percent=99" """
+
+        lsat7_2002_pca_univar_out = [
+            """n=250325
+            null_cells=0
+            cells=250325
+            min=0
+            max=255
+            range=255
+            mean=60.6958074503146
+            mean_of_abs=60.6958074503146
+            stddev=32.8850846003739
+            variance=1081.42878917375
+            coeff_var=54.1801583697417
+            sum=15193678
+            first_quartile=36
+            median=51
+            third_quartile=77
+            percentile_90=101""",
+            """n=250325
+            null_cells=0
+            cells=250325
+            min=0
+            max=255
+            range=255
+            mean=106.099418755618
+            mean_of_abs=106.099418755618
+            stddev=26.4487056926998
+            variance=699.534032819051
+            coeff_var=24.928228639612
+            sum=26559337
+            first_quartile=88
+            median=104
+            third_quartile=121
+            percentile_90=137""",
+            """n=250325
+            null_cells=0
+            cells=250325
+            min=0
+            max=255
+            range=255
+            mean=74.1768980325577
+            mean_of_abs=74.1768980325577
+            stddev=14.1956266450161
+            variance=201.515815844691
+            coeff_var=19.1375307158104
+            sum=18568332
+            first_quartile=67
+            median=74
+            third_quartile=81
+            percentile_90=88""",
+            """n=250325
+            null_cells=0
+            cells=250325
+            min=0
+            max=255
+            range=255
+            mean=113.285145311096
+            mean_of_abs=113.285145311096
+            stddev=10.689092045444
+            variance=114.256688755974
+            coeff_var=9.43556369733241
+            sum=28358104
+            first_quartile=109
+            median=114
+            third_quartile=118
+            percentile_90=122""",
+            """n=250325
+            null_cells=0
+            cells=250325
+            min=0
+            max=255
+            range=255
+            mean=110.346713272745
+            mean_of_abs=110.346713272745
+            stddev=8.43087149474902
+            variance=71.0795941609716
+            coeff_var=7.64034672596938
+            sum=27622541
+            first_quartile=106
+            median=110
+            third_quartile=114
+            percentile_90=118""",
+            """n=250325
+            null_cells=0
+            cells=250325
+            min=0
+            max=255
+            range=255
+            mean=115.238465994208
+            mean_of_abs=115.238465994208
+            stddev=8.97064489504434
+            variance=80.4724698329851
+            coeff_var=7.78441887233665
+            sum=28847069
+            first_quartile=110
+            median=115
+            third_quartile=121
+            percentile_90=126""",
+        ]
+
+        for i in range(1, 7):
+            # Asserting the results givien from r.info
+            self.assertRasterFitsInfo(
+                raster=f"lsat7_2002_pca.{i}",
+                reference=lsat7_2002_pca_info_out,
+                precision=3,
+            )
+
+            # Asserting the results givien from r.univar
+            univar_out = lsat7_2002_pca_univar_out[i - 1]
+            self.assertModuleKeyValue(
+                "r.univar",
+                flags="eg",
+                map=f"lsat7_2002_pca.{i}",
+                reference=univar_out,
+                precision=3,
+                sep="=",
+            )
+
+
+if __name__ == "__main__":
+    from grass.gunittest.main import test
+
+    test()