Basic usage

Notebook setup

[1]:

%matplotlib inline
%load_ext autoreload
%autoreload 2

[2]:

import sys

sys.path.append("../..")

[3]:

from s1etad import Sentinel1Etad

Sentinel1Etad product

[4]:

filename = (
    "data/"
    "S1B_IW_ETA__AXDV_20200124T221416_20200124T221444_019964_025C43_0A63.SAFE"
)

[5]:

eta = Sentinel1Etad(filename)

[6]:

eta

[6]:

Sentinel1Etad("data/S1B_IW_ETA__AXDV_20200124T221416_20200124T221444_019964_025C43_0A63.SAFE")  # 0x7abdc4281520
Number of Sentinel-1 slices: 1
Sentinel-1 products list:
  S1B_IW_SLC__1ADV_20200124T221416_20200124T221444_019964_025C43_95FB.SAFE
Number of swaths: 3
Swath list: IW1, IW2, IW3
Azimuth time:
  min: 2020-01-24 22:14:16.480938
  max: 2020-01-24 22:14:44.428152
Range time:
  min: 0.005328684957372668
  max: 0.006383362874313361
Grid sampling:
  x: 8.131672451354599e-07
  y: 0.02932551319648094
  unit: s
Grid spacing:
  x: 200.0
  y: 200.0
  unit: m
Processing settings:
  troposphericDelayCorrection: True
  ionosphericDelayCorrection: True
  solidEarthTideCorrection: True
  bistaticAzimuthCorrection: True
  dopplerShiftRangeCorrection: True
  FMMismatchAzimuthCorrection: True

Check which corrections have been enabled

[7]:

eta.processing_setting()

[7]:

{'troposphericDelayCorrection': True,
 'ionosphericDelayCorrection': True,
 'solidEarthTideCorrection': True,
 'bistaticAzimuthCorrection': True,
 'dopplerShiftRangeCorrection': True,
 'FMMismatchAzimuthCorrection': True}

The burst catalogue

It is a pandas dataframe to allow easy filtering.

See also use cases in the “Use case 1: Selecting the bursts” section for a more complete explanation on the burst catalogue and the query mechanism.

[8]:

eta.burst_catalogue.head()

[8]:

	bIndex	pIndex	sIndex	productID	swathID	azimuthTimeMin	azimuthTimeMax
0	1	1	1	S1B_IW_SLC__1ADV_20200124T221416_20200124T2214...	IW1	2020-01-24 22:14:16.480938000	2020-01-24 22:14:19.618767912
1	4	1	1	S1B_IW_SLC__1ADV_20200124T221416_20200124T2214...	IW1	2020-01-24 22:14:19.237536240	2020-01-24 22:14:22.375366152
2	7	1	1	S1B_IW_SLC__1ADV_20200124T221416_20200124T2214...	IW1	2020-01-24 22:14:21.994134480	2020-01-24 22:14:25.131964392
3	10	1	1	S1B_IW_SLC__1ADV_20200124T221416_20200124T2214...	IW1	2020-01-24 22:14:24.750732721	2020-01-24 22:14:27.888562633
4	13	1	1	S1B_IW_SLC__1ADV_20200124T221416_20200124T2214...	IW1	2020-01-24 22:14:27.507330961	2020-01-24 22:14:30.645160873

Tip: the total number of bursts in a product can be retrieved as follows:

[9]:

print("Total number of bursts:", len(eta.burst_catalogue))

Total number of bursts: 28

Swath objects

How many swaths are stored in a product?

[10]:

print("Number of swaths:", eta.number_of_swath)
print("Swath list:", eta.swath_list)

Number of swaths: 3
Swath list: ['IW1', 'IW2', 'IW3']

How to retrieve a Sentinel1EtadSwath object

[11]:

swath = eta["IW2"]

[12]:

swath

[12]:

Sentinel1EtadSwath("/IW2")  0x7abdac0b96a0
Swaths ID: IW2
Number of bursts: 9
Burst list: [2, 5, 8, 11, 14, 17, 20, 23, 26]
Sampling start:
  x: 0.00031062988764174633
  y: 0.9384164222873892
  units: s
Sampling:
  x: 8.131672451354599e-07
  y: 0.02932551319648094
  units: s

Burst objects

[13]:

burst = swath[2]

[14]:

burst

[14]:

Sentinel1EtadBurst("/IW2/Burst0002")  0x7abd6f5a29f0
Swaths ID: IW2
Burst index: 2
Shape: (109, 476)
Sampling start:
  x: 0.00031062988764174633
  y: 0.9384164222873892
  units: s
Sampling:
  x: 8.131672451354599e-07
  y: 0.02932551319648094
  units: s

NOTE: one can only get bursts whose index is present in the “burst list” of the swath

[15]:

swath.burst_list

[15]:

[2, 5, 8, 11, 14, 17, 20, 23, 26]

[16]:

try:
    swath[1]
except IndexError as exc:
    print("ERROR: Ops someting went wrong:", repr(exc))

ERROR: Ops someting went wrong: IndexError('Burst0001 not found in /IW2')

String representation

Please note that the string representation of Sentinel1Etad object is a “one-line” string providing only basic information:

[17]:

print("Product:", str(eta))
print("Swath:", str(swath))
print("Burst:", str(burst))

Product: Sentinel1Etad("S1B_IW_ETA__AXDV_20200124T221416_20200124T221444_019964_025C43_0A63.SAFE")
Swath: Sentinel1EtadSwath("/IW2")  0x7abdac0b96a0
Burst: Sentinel1EtadBurst("/IW2/Burst0002")  0x7abd6f5a29f0

Anyway in Jupyter environments a richer representation is also available:

[18]:

eta

[18]:

Sentinel1Etad("data/S1B_IW_ETA__AXDV_20200124T221416_20200124T221444_019964_025C43_0A63.SAFE")  # 0x7abdc4281520
Number of Sentinel-1 slices: 1
Sentinel-1 products list:
  S1B_IW_SLC__1ADV_20200124T221416_20200124T221444_019964_025C43_95FB.SAFE
Number of swaths: 3
Swath list: IW1, IW2, IW3
Azimuth time:
  min: 2020-01-24 22:14:16.480938
  max: 2020-01-24 22:14:44.428152
Range time:
  min: 0.005328684957372668
  max: 0.006383362874313361
Grid sampling:
  x: 8.131672451354599e-07
  y: 0.02932551319648094
  unit: s
Grid spacing:
  x: 200.0
  y: 200.0
  unit: m
Processing settings:
  troposphericDelayCorrection: True
  ionosphericDelayCorrection: True
  solidEarthTideCorrection: True
  bistaticAzimuthCorrection: True
  dopplerShiftRangeCorrection: True
  FMMismatchAzimuthCorrection: True

Iteration

It is possible to iterate over products and swats in the same way one does it with any other python container.

[19]:

for swath in eta:
    print(swath)
    for burst in swath:
        print(burst.burst_index, burst.swath_id, burst)
    print()

Sentinel1EtadSwath("/IW1")  0x7abd6f5a3410
1 IW1 Sentinel1EtadBurst("/IW1/Burst0001")  0x7abd6f5a34a0
4 IW1 Sentinel1EtadBurst("/IW1/Burst0004")  0x7abd6f5a0ce0
7 IW1 Sentinel1EtadBurst("/IW1/Burst0007")  0x7abd6f5a2f00
10 IW1 Sentinel1EtadBurst("/IW1/Burst0010")  0x7abd6f5a3bf0
13 IW1 Sentinel1EtadBurst("/IW1/Burst0013")  0x7abd6f5a2e10
16 IW1 Sentinel1EtadBurst("/IW1/Burst0016")  0x7abd6f5a38f0
19 IW1 Sentinel1EtadBurst("/IW1/Burst0019")  0x7abd6f5a3a10
22 IW1 Sentinel1EtadBurst("/IW1/Burst0022")  0x7abd6f5a3710
25 IW1 Sentinel1EtadBurst("/IW1/Burst0025")  0x7abd6f5a27e0
28 IW1 Sentinel1EtadBurst("/IW1/Burst0028")  0x7abd6f5a3560

Sentinel1EtadSwath("/IW2")  0x7abdac0b96a0
2 IW2 Sentinel1EtadBurst("/IW2/Burst0002")  0x7abd6f5a29f0
5 IW2 Sentinel1EtadBurst("/IW2/Burst0005")  0x7abd6f5a37d0
8 IW2 Sentinel1EtadBurst("/IW2/Burst0008")  0x7abd6f5a2c60
11 IW2 Sentinel1EtadBurst("/IW2/Burst0011")  0x7abd6f5a2ba0
14 IW2 Sentinel1EtadBurst("/IW2/Burst0014")  0x7abd6f5a3c50
17 IW2 Sentinel1EtadBurst("/IW2/Burst0017")  0x7abd6f5a28d0
20 IW2 Sentinel1EtadBurst("/IW2/Burst0020")  0x7abd6f5a1640
23 IW2 Sentinel1EtadBurst("/IW2/Burst0023")  0x7abd6f5a30e0
26 IW2 Sentinel1EtadBurst("/IW2/Burst0026")  0x7abd6f5a3740

Sentinel1EtadSwath("/IW3")  0x7abd6f5a03b0
3 IW3 Sentinel1EtadBurst("/IW3/Burst0003")  0x7abd6f5a3470
6 IW3 Sentinel1EtadBurst("/IW3/Burst0006")  0x7abd6f5a3cb0
9 IW3 Sentinel1EtadBurst("/IW3/Burst0009")  0x7abd6f5a3950
12 IW3 Sentinel1EtadBurst("/IW3/Burst0012")  0x7abd6f5a3b90
15 IW3 Sentinel1EtadBurst("/IW3/Burst0015")  0x7abd6f5a18e0
18 IW3 Sentinel1EtadBurst("/IW3/Burst0018")  0x7abd6f5a3d40
21 IW3 Sentinel1EtadBurst("/IW3/Burst0021")  0x7abd6f5a3260
24 IW3 Sentinel1EtadBurst("/IW3/Burst0024")  0x7abd6f5a3da0
27 IW3 Sentinel1EtadBurst("/IW3/Burst0027")  0x7abd6f5a3e30

How to iterate only on selected items

It is also possible to iterate on a sub-set of the products swaths (or a sub-set of the swath bursts):

[20]:

for swath in eta.iter_swaths(["IW1", "IW2"]):  # no 'IW3'
    # list of bursts
    odd_bursts = [idx for idx in swath.burst_list if idx % 2 != 0]
    for burst in swath.iter_bursts(odd_bursts):
        print(f"{burst.burst_index:2} {burst.swath_id} {burst}")

 1 IW1 Sentinel1EtadBurst("/IW1/Burst0001")  0x7abd6f5a34a0
 7 IW1 Sentinel1EtadBurst("/IW1/Burst0007")  0x7abd6f5a2f00
13 IW1 Sentinel1EtadBurst("/IW1/Burst0013")  0x7abd6f5a2e10
19 IW1 Sentinel1EtadBurst("/IW1/Burst0019")  0x7abd6f5a3a10
25 IW1 Sentinel1EtadBurst("/IW1/Burst0025")  0x7abd6f5a27e0
 5 IW2 Sentinel1EtadBurst("/IW2/Burst0005")  0x7abd6f5a37d0
11 IW2 Sentinel1EtadBurst("/IW2/Burst0011")  0x7abd6f5a2ba0
17 IW2 Sentinel1EtadBurst("/IW2/Burst0017")  0x7abd6f5a28d0
23 IW2 Sentinel1EtadBurst("/IW2/Burst0023")  0x7abd6f5a30e0

How to iterate on query results

The query mechanism is explained extensively in the following.

Queries can be performed using the Sentinel1Etad.query_burst method.

A simple example is a query for a specific swath:

[21]:

query_result = eta.query_burst(swath="IW3")

for swath in eta.iter_swaths(query_result):
    for burst in swath.iter_bursts(query_result):
        print(burst)

Sentinel1EtadBurst("/IW3/Burst0003")  0x7abd6f5a3470
Sentinel1EtadBurst("/IW3/Burst0006")  0x7abd6f5a3cb0
Sentinel1EtadBurst("/IW3/Burst0009")  0x7abd6f5a3950
Sentinel1EtadBurst("/IW3/Burst0012")  0x7abd6f5a3b90
Sentinel1EtadBurst("/IW3/Burst0015")  0x7abd6f5a18e0
Sentinel1EtadBurst("/IW3/Burst0018")  0x7abd6f5a3d40
Sentinel1EtadBurst("/IW3/Burst0021")  0x7abd6f5a3260
Sentinel1EtadBurst("/IW3/Burst0024")  0x7abd6f5a3da0
Sentinel1EtadBurst("/IW3/Burst0027")  0x7abd6f5a3e30