Reading coordinates in and using them in an array-CodePudding

I have ajson which I have pulled a list of coordinates of 10 sided polygons (attached an example).

I need to create an array from these coordinates that will plot them on a 128 x 128 square as filled in polygons so that I can multiply it with another array.

f=open('139cm_2000_frame27.json')
data=json.load(f)
shapes=data["shapes"]   
for i in shapes:
    for c in i["points"]:
        print(c)

This code prints the coordinates as such:

[59.10047478151446, 18.879430437885873]
[58.04359793578868, 16.37330203102605]
[58.661631924538575, 13.724584936383643]
[60.71850877026435, 11.94499905752918]
[63.42857142857143, 11.714285714285715]
[65.75666807562841, 13.120569562114127]
[66.81354492135418, 15.62669796897395]
[66.19551093260428, 18.275415063616357]
[64.13863408687851, 20.05500094247082]
[88.71428571428572, 82.42857142857143]
[85.63470409582908, 81.33512050565437]
[83.78598455752919, 78.6403674679397]
[83.8742751273506, 75.3736163845474]
[85.86585180850763, 72.78265513654777]
[89.0, 71.85714285714285]
.............

The first 10 make one polygon , the second 10 another... I need to get these coordinates of these polygons and put them on a 128x128 array. Essentially it will look like this, but in an array form, this is just plotted using matplotlib

CodePudding user response：

You can use the json library to work with json objects. If you need to load the json from a file use json.load() like so:

import json
with open('example.json', 'r') as f:
    versions = json.load(f)['versions']

and use loads when from a string:

import json
json_str = '{"versions": 10}'
versions = json.loads(json_str)['versions']

CodePudding user response：

Ok, you’ve managed to get some way. You now have to navigate the ‘dicts within lists within dicts’. This code will simply print out all the coordinates of all the shapes:

f=open('139cm_2000_frame27.json') 
data=json.load(f) 
shapes=data["shapes"] 
for i in shapes: 
    print(i[‘label’])   # prints the label first
    for c in i[‘points’]:
        print(c)       # a list containing coordinates

(Sorry, but the single quoted strings are malformed. I’ll have to fix those later)