Say I have some data with timestamps, prices and amounts. This data can be quite large and matching conditions could occur anywhere in the group. A simple example shown below:
[{"date":1387496043,"price":19.379,"amount":1.000000}
{"date":1387496044,"price":20.20,"amount":2.00000}
{"date":1387496044,"price":10.00,"amount":0.10000}
{"date":1387496044,"price":20.20,"amount":0.300000}]
How could I sort this so I combine the amounts of any item that has the same timestamp and same price?
So the results look like (note the 2.0 and 0.3 amounts have been summed together):
[{"date":1387496043,"price":19.379,"amount":1.000000}
{"date":1387496044,"price":20.20,"amount":2.30000}
{"date":1387496044,"price":10.00,"amount":0.10000}]
I've tried a number of convoluted methods (using Python 2.7.3), but I don't know python very well. I'm sure there's a good way to find 2 matching values and then updating one with new amount and removing the duplicate.
FYI Here is the test data
L=[{"date":1387496043,"price":19.379,"amount":1.000000},{"date":1387496044,"price":20.20,"amount":2.00000},{"date":1387496044,"price":10.00,"amount":0.10000},{"date":1387496044,"price":20.20,"amount":0.300000}]