diff options
| -rwxr-xr-x | python/slope.py | 27 |
1 files changed, 12 insertions, 15 deletions
diff --git a/python/slope.py b/python/slope.py index c545b9f..e0ca3e1 100755 --- a/python/slope.py +++ b/python/slope.py @@ -122,11 +122,10 @@ def detach_display(): fig.canvas.callbacks.disconnect(cid) #print(xMarker) -def plot_curve(MY, PX): +def plot_curve(PX): """ Fit straight line to channel elevation data. Pixel size PX is - used to convert pixel indices to co-ordinate values. The maximum - co-ordinate value in the y-direction is MY. + used to convert pixel indices to co-ordinate values. """ # sort markers by y value #yx = list(zip(yMarker, xMarker)) @@ -161,14 +160,13 @@ def plot_curve(MY, PX): # Add to list. Repeat. # Fit with polyfit - m, c = np.polyfit([MY - y*PX for y in ych], zch, 1) + m, c = np.polyfit([(0.5 + y)*PX for y in ych], zch, 1) print('gradient =', m, 'intercept =', c) - # print('MY =', MY) fig, ax = plt.subplots() - line1, = ax.plot([MY - y*PX for y in ych], zch) - line2, = ax.plot([MY - y*PX for y in ych], - [c + m*MY - m*y*PX for y in ych], '--') + line1, = ax.plot([(0.5 + y)*PX for y in ych], zch) + line2, = ax.plot([(0.5 + y)*PX for y in ych], + [c + m*(0.5 + y)*PX for y in ych], '--') ax.set_xlabel('Distance / m') ax.set_ylabel('Height / m') ax.set_title('Channel profile') @@ -181,18 +179,17 @@ def plot_curve(MY, PX): #fig.canvas.draw() #fig.canvas.flush_events() -def save_xyz(MY, PX): +def save_xyz(PX): """ Write channel elevation data to file. Pixel size PX is used to - convert pixel indices to co-ordinate values. The maximum - co-ordinate value in the y-direction is MY. + convert pixel indices to co-ordinate values. """ with open('1D.txt', 'w') as f: for xitem, yitem, zitem in zip(reversed(xch), reversed(ych), reversed(zch)): - f.write('{:.2f} {:.2f} {:.4f}\n'.format(PX/2.0+xitem*PX, - MY-yitem*PX, + f.write('{:.2f} {:.2f} {:.4f}\n'.format((0.5 + xitem)*PX, + (0.5 + yitem)*PX, zitem)) @@ -217,8 +214,8 @@ while (True): elif(input_str == "m"): detach_display() elif(input_str == "p"): - plot_curve(ytp[-1], DY) + plot_curve(DY) elif(input_str == "s"): - save_xyz(ytp[-1], DY) + save_xyz(DY) #print("End.") |