fixup! Use extension 1 in rotation calculations

Author: achaikou

python/examples/make-rotated-rev2.py

@@ -9,10 +9,10 @@ def product(f):
 
 # this program turns the rev1 file into rev2 file with CDP values set to
 # different set of cdp-x and cdp-y coordinates in standard and ext1 headers.
-# values are taken from make-rotated-copies.py script
+# The formulas are taken from make-rotated-copies.py script
 
 def main():
-    if len(sys.argv) < 2:
+    if len(sys.argv) != 3:
         sys.exit(
             "Usage: {} [source-file] [destination-file]".format(sys.argv[0]))
 
@@ -45,13 +45,13 @@ def main():
     with segyio.open(dstfile, 'r+') as dst:
         for i, (x, y) in enumerate(product(src)):
             trh = dst.traceheader[i][0]
-            # right
+            # "right" rotation formula
             trh.cdp_x = y
             trh.cdp_y = 100 - x
             trh.co_scal = 1
 
             trh = dst.traceheader[i][1]
-            # left
+            # "left" rotation formula
             trh.cdp_x = (100 - y) * 21
             trh.cdp_y = x * 21
 

test-data/README.md

@@ -60,9 +60,9 @@ To recreate:
 File below is used to test revision 2 features and is created with:
 `python python/examples/make-rotated-rev2.py test-data/small.sgy test-data/rotated-small-rev2.sgy`
 
-| File                   | Purpose                                                                   |
-|------------------------|-------------------------------------------------------------------------- |
-| rotated-small-rev2.sgy | Revision 2 file with different values on standard and extension 1 levels. |
+| File                   | Purpose                                                                    |
+|------------------------|--------------------------------------------------------------------------- |
+| rotated-small-rev2.sgy | Revision 2 file with different values on standard and extension 1 headers. |
 
 ## Dimensions sorting test files