Naive implementation to estimate the duration of a print

duration.py

+#!/usr/bin/env python
+from math import sqrt
+
+of=open("../PrusaMendel/stl/calibration_export.gcode")
+g=[i.replace("\n","").replace("\r","") for i in of]
+of.close
+
+def get_value(axis, parts):
+    for i in parts:
+        if (axis in i):
+            return float(i[1:])
+    return None
+
+
+total_duration = 0
+starting_velocity = 0
+global_feedrate = 0
+initial_feedrate = 0
+X_last_position = 0
+Y_last_position = 0
+for i in g:
+    if "G1" in i and ("X" in i or "Y" in i or "F" in i):
+        parts = i.split(" ")
+        X = get_value("X", parts[1:])
+        Y = get_value("Y", parts[1:])
+        F = get_value("F", parts[1:])
+
+        if (X is None and Y is None and F is not None):
+            global_feedrate = F
+            continue
+        
+        feedrate = 0
+        if (F is None):
+            feedrate = global_feedrate
+        else:
+            feedrate = F
+
+        distance = 0
+        if (X is not None and Y is None):
+            distance = X - X_last_position
+            X_last_position = X
+        elif (X is None and Y is not None):
+            distance = Y - Y_last_position
+            Y_last_position = Y
+        elif (X is not None and Y is not None):
+            X_distance = X - X_last_position
+            Y_distance = Y - Y_last_position
+            distance = sqrt(X_distance * X_distance + Y_distance * Y_distance)
+            X_last_position = X
+            Y_last_position = Y        
+
+        time_for_move = distance / (feedrate / 60)
+        acceleration = (feedrate - initial_feedrate) / time_for_move
+
+        halfway_feedrate = initial_feedrate + acceleration * time_for_move / 2
+
+        duration = 0
+        if (halfway_feedrate == feedrate):
+            time_full_feedrate = (feedrate - initial_feedrate) / acceleration
+            distance_full_feedrate = (0.5 * (feedrate + initial_feedrate)) * time_full_feedrate
+            duration = time_full_feedrate * 2 + (distance - distance_full_feedrate * 2) / feedrate
+        else:
+            duration = (halfway_feedrate * 2 - initial_feedrate) / acceleration
+
+        total_duration += duration
+    
+    
+print ("Total duration (in minutes): {0}".format(total_duration / 60))