readgssi.arrayops (array manipulation)

readgssi.arrayops.distance_normalize(header, ar, gps, verbose=False)

Distance normalization algorithm. Uses a GPS array to calculate expansion and contraction needed to convert from time-triggered to distance-normalized sampling interval. Then, the samples per meter is recalculated and inserted into the header for proper plotting.

Usage described in the Distance normalization section of the tutorial.

Parameters
Return type

header (dict), radar array (numpy.ndarray), gps (False or pandas.DataFrame)

readgssi.arrayops.flip(ar, verbose=False)

Read the array backwards. Used to reverse line direction. Usage covered in the Reversing tutorial section.

Parameters
  • ar (numpy.ndarray) – Input data array

  • verbose (bool) – Verbose, defaults to False

Return type

radar array (numpy.ndarray)

readgssi.arrayops.reducex(ar, header, by=1, chnum=1, number=1, verbose=False)

Reduce the number of traces in the array by a number. Not the same as stack() since it doesn’t sum adjacent traces, however stack() uses it to resize the array prior to stacking.

Used by stack() and distance_normalize() but not accessible from the command line or readgssi.readgssi().

Parameters
  • ar (numpy.ndarray) – Input data array

  • by (int) – Factor to reduce by. Default is 1.

  • chnum (int) – Chunk number to display in console. Default is 1.

  • number (int) – Number of chunks to display in console. Default is 1.

  • verbose (bool) – Verbose, defaults to False.

Return type

radar array (numpy.ndarray)

readgssi.arrayops.stack(ar, header, stack='auto', verbose=False)

Stacking algorithm. Stacking is the process of summing adjacent traces in order to reduce noise — the thought being that random noise around zero will cancel out and data will either add or subtract, making it easier to discern.

It is also useful for displaying long lines on a computer screen. Usage is covered in the Stacking section of the tutorial.

stack='auto' results in an approximately 2.5:1 x:y axis ratio. stack=3 sums three adjacent traces into a single trace across the width of the array.

Parameters
  • ar (numpy.ndarray) – Input data array

  • by (int) – Factor to stack by. Default is “auto”.

Return type

radar array (numpy.ndarray)