Python Minizinc gives sometimes a different result than Minizinc IDE - python
Depending on the input data I sometimes obtain a different result (different objective and solution) when using the Minizinc Python library or the Minizinc IDE.
My Python code is the following:
from minizinc import Instance, Model, Solver
import datetime
gecode = Solver.lookup("gecode")
model = Model()
model.add_file("./model.mzn")
model.add_file("./data.dzn", parse_data=True)
instance = Instance(gecode, model)
TIMELIMIT = datetime.timedelta(seconds=60)
result = instance.solve(timeout=TIMELIMIT)
print(result.status)
result.solution
As far as I can tell, my solver parameters are the same in the IDE, I use the same model and same data.
I can see the following command in the IDE:
Command: minizinc --json-stream --param-file-no-push /private/var/folders/hf/_75w1jh170x75y2_2vwt60lc0000gn/T/mzn_KneEzb.mpc model.mzn data.dzn
Configuration:
{
"intermediate-solutions": true,
"solver": "org.gecode.gecode#6.3.0",
"time-limit": 60000
}
In one specific input data instance, IDE finds an optimal at obj = 80, and Python finds obj = 104.
In another instance of input data, both IDE and Python find the same obj.
What can explain this different result?
Update: I am adding the MiniZinc model and data:
model.mzn
int: nNodes = nC+2*nV;
% ============== Vehicle Routing Problem ============= %
include "globals.mzn";
int: nC; int: nV; int: timeBudget;
set of int: VEHICLE = 1..nV;
set of int: CUSTOMER = 1..nC;
set of int: NODES = 1..nNodes;
set of int: START_DEPOT_NODES = nC+1..nC+nV;
set of int: END_DEPOT_NODES = nC+nV+1..nC+2*nV;
set of int: TIME = 0..timeBudget;
array[NODES] of int: serviceTime;
array[NODES, NODES] of int: distance;
% Time windows
% departure time must be between TimeWindows[client_i, 1] and TimeWindows[client_i, 2]
array[1..nC, 1..2] of int: TimeWindows;
% -------- variables ------------- %
array[NODES] of var VEHICLE: vehicle;
array[NODES] of var NODES: successor;
array[NODES] of var TIME: arrivalTime;
% -------- Start Nodes, End Nodes constraints ---------- %
constraint forall (n in START_DEPOT_NODES) % associate each start
( vehicle[n] = n-nC ); % node with a vehicle
constraint forall (n in END_DEPOT_NODES) % associate each end
( vehicle[n] = n-nC-nV ); % node with a vehicle
% -------- Successor Nodes constraints ---------- %
constraint forall (n in nC+nV+1..nC+2*nV-1) % successors of end nodes
( successor[n] = n-nV+1 ); % are start nodes
constraint successor[nC+2*nV] = nC+1;
constraint forall (n in START_DEPOT_NODES) % vehicles leave the
( arrivalTime[n] = 0 ); % depot at time zero
constraint circuit(successor); % hamiltonian circuit
constraint forall (n in CUSTOMER) % use the same vehicle
( vehicle[successor[n]] = vehicle[n] ); % along a subtour
constraint forall (n in 1..nC+nV)
( arrivalTime[n] + serviceTime[n] + distance[n,successor[n]]
<= arrivalTime[successor[n]] ); % time constraints
% -------- Time windows constraints -------------- %
constraint
forall(i in 1..nC)(
TimeWindows[i, 1] <= arrivalTime[i]
);
constraint
forall(i in 1..nC)(
TimeWindows[i, 2] >= arrivalTime[i]
);
% -------- objective ------------ %
% minimize distance (could be travel time in hours)
var int: obj = (sum (n in NODES) (distance[n,successor[n]]));
solve minimize obj; % expected overall travel time of each vehicle
% -------- output ------------ %
output ["obj = \(obj) \n"];
data.dzn
nV =5; nC = 40; timeBudget = 5000;
serviceTime = [ 6, 7, 3, 10, 2, 5, 2, 9, 7, 6, 5, 7, 7, 9, 9, 3, 7, 9, 1, 2, 5, 4, 7, 6, 3, 4, 6, 6, 2, 1, 10, 1, 5, 4, 10, 2, 10, 9, 2, 10, 5, 6, 4, 9, 9, 10, 6, 6, 6, 5];
distance = [| 0, 3, 7, 2, 10, 1, 6, 1, 10, 7, 3, 9, 5, 10, 5, 6, 2, 4, 3, 6, 5, 4, 4, 8, 7, 8, 8, 7, 8, 8, 9, 5, 2, 2, 9, 1, 2, 3, 1, 6, 6, 1, 1, 5, 3, 1, 5, 1, 4, 9
|5, 0, 7, 7, 6, 9, 1, 2, 2, 7, 10, 1, 9, 7, 5, 9, 4, 9, 8, 8, 4, 2, 10, 6, 1, 2, 7, 7, 4, 6, 5, 7, 9, 1, 10, 8, 6, 9, 1, 8, 6, 10, 7, 5, 7, 4, 10, 6, 8, 2
|7, 7, 0, 8, 10, 10, 6, 5, 9, 7, 5, 3, 2, 8, 10, 6, 10, 9, 8, 2, 1, 9, 10, 7, 4, 6, 1, 5, 8, 8, 9, 1, 2, 2, 6, 3, 2, 7, 1, 3, 6, 9, 7, 3, 6, 6, 6, 3, 3, 8
|7, 3, 6, 0, 10, 5, 8, 2, 5, 7, 1, 10, 8, 2, 5, 6, 9, 7, 1, 2, 1, 3, 3, 10, 10, 3, 9, 7, 2, 3, 4, 10, 10, 7, 6, 4, 9, 9, 8, 4, 1, 5, 6, 3, 10, 4, 5, 9, 3, 7
|5, 4, 9, 4, 0, 9, 8, 1, 1, 4, 9, 2, 10, 4, 4, 9, 7, 6, 8, 10, 5, 5, 5, 7, 8, 10, 10, 7, 3, 1, 6, 2, 4, 6, 5, 3, 10, 1, 2, 7, 3, 1, 2, 8, 1, 5, 10, 1, 5, 5
|2, 4, 4, 4, 7, 0, 8, 9, 3, 2, 8, 7, 7, 7, 5, 9, 9, 8, 3, 2, 3, 8, 3, 2, 8, 4, 1, 6, 4, 3, 2, 3, 6, 4, 2, 10, 6, 5, 5, 5, 10, 6, 4, 10, 10, 10, 8, 3, 2, 4
|5, 3, 6, 3, 7, 1, 0, 9, 10, 5, 4, 10, 4, 8, 9, 8, 6, 4, 1, 9, 2, 1, 4, 4, 6, 6, 9, 1, 9, 1, 7, 2, 1, 5, 4, 3, 6, 4, 4, 10, 4, 10, 7, 10, 4, 7, 8, 1, 3, 4
|9, 1, 5, 4, 6, 5, 10, 0, 4, 8, 10, 7, 5, 10, 7, 5, 4, 4, 10, 7, 8, 6, 2, 7, 9, 6, 2, 3, 9, 8, 3, 9, 4, 6, 5, 1, 4, 6, 7, 6, 9, 1, 9, 5, 5, 5, 5, 6, 7, 1
|5, 6, 4, 2, 9, 1, 5, 4, 0, 3, 3, 3, 6, 1, 4, 10, 1, 10, 10, 4, 8, 4, 7, 2, 9, 4, 4, 4, 4, 10, 8, 9, 9, 7, 9, 3, 9, 9, 3, 7, 1, 9, 2, 1, 3, 9, 8, 4, 1, 8
|10, 5, 8, 5, 7, 2, 1, 1, 5, 0, 7, 2, 5, 10, 5, 7, 1, 7, 7, 8, 3, 1, 3, 3, 9, 10, 1, 7, 1, 3, 4, 1, 8, 8, 4, 4, 5, 3, 3, 2, 3, 9, 4, 2, 3, 8, 5, 7, 9, 9
|9, 5, 8, 1, 2, 3, 1, 5, 10, 4, 0, 8, 10, 9, 3, 5, 1, 2, 10, 4, 9, 2, 1, 1, 10, 1, 4, 7, 7, 8, 10, 2, 6, 7, 8, 7, 4, 3, 5, 7, 7, 8, 10, 2, 3, 4, 7, 6, 6, 7
|8, 10, 3, 2, 9, 4, 2, 3, 7, 4, 8, 0, 9, 5, 1, 6, 7, 7, 9, 5, 4, 2, 3, 8, 7, 1, 2, 10, 9, 5, 4, 4, 4, 9, 3, 4, 9, 9, 6, 9, 6, 10, 9, 3, 8, 3, 9, 3, 6, 2
|1, 1, 6, 3, 6, 1, 9, 3, 9, 2, 6, 1, 0, 5, 10, 5, 1, 7, 7, 5, 3, 1, 7, 3, 7, 3, 5, 10, 1, 8, 3, 6, 2, 6, 2, 1, 2, 5, 8, 8, 10, 4, 6, 1, 10, 2, 3, 3, 1, 1
|3, 5, 3, 4, 7, 7, 10, 9, 5, 3, 5, 3, 8, 0, 5, 6, 5, 9, 8, 8, 4, 1, 6, 8, 5, 9, 7, 5, 7, 5, 5, 1, 3, 6, 7, 9, 9, 10, 2, 3, 2, 6, 8, 9, 10, 3, 2, 1, 4, 5
|6, 5, 6, 8, 6, 5, 2, 9, 5, 3, 10, 8, 4, 6, 0, 10, 2, 2, 3, 3, 7, 5, 5, 9, 4, 2, 10, 10, 4, 4, 2, 3, 4, 8, 10, 6, 1, 1, 1, 9, 8, 1, 9, 5, 6, 9, 7, 5, 7, 8
|6, 9, 8, 1, 8, 10, 7, 1, 4, 2, 8, 1, 4, 3, 2, 0, 3, 7, 4, 9, 5, 2, 10, 2, 8, 9, 3, 3, 2, 8, 9, 4, 1, 10, 2, 10, 9, 6, 10, 2, 9, 9, 9, 2, 4, 8, 7, 9, 9, 5
|8, 3, 4, 5, 5, 5, 4, 6, 6, 2, 6, 6, 5, 3, 4, 6, 0, 7, 1, 7, 1, 8, 5, 10, 8, 8, 9, 6, 10, 3, 10, 6, 4, 6, 8, 9, 9, 9, 1, 7, 3, 5, 4, 7, 3, 7, 2, 10, 10, 7
|10, 7, 1, 4, 7, 6, 2, 5, 1, 9, 7, 9, 6, 9, 6, 2, 3, 0, 5, 4, 3, 4, 2, 5, 5, 1, 1, 1, 1, 10, 4, 5, 6, 2, 2, 7, 10, 9, 4, 3, 4, 3, 9, 2, 6, 10, 9, 6, 4, 2
|2, 10, 10, 8, 5, 4, 4, 2, 1, 7, 7, 9, 2, 2, 7, 1, 7, 4, 0, 9, 5, 3, 10, 4, 10, 9, 7, 3, 4, 1, 8, 6, 1, 8, 2, 6, 1, 1, 6, 7, 3, 3, 10, 1, 10, 5, 3, 1, 5, 9
|8, 4, 2, 6, 5, 5, 6, 2, 1, 3, 10, 10, 10, 4, 3, 3, 1, 4, 6, 0, 6, 4, 3, 10, 4, 5, 3, 10, 1, 6, 6, 8, 4, 8, 4, 7, 4, 5, 9, 1, 3, 6, 1, 5, 10, 3, 10, 7, 7, 5
|3, 9, 8, 5, 2, 7, 9, 9, 10, 4, 9, 10, 10, 2, 8, 2, 9, 2, 2, 8, 0, 2, 5, 3, 9, 10, 9, 8, 2, 2, 5, 4, 7, 6, 5, 7, 6, 1, 4, 10, 6, 4, 4, 8, 4, 5, 4, 3, 10, 5
|4, 2, 5, 7, 7, 5, 9, 8, 2, 9, 5, 6, 5, 4, 4, 1, 1, 5, 8, 8, 4, 0, 2, 10, 8, 6, 8, 8, 3, 8, 2, 4, 6, 7, 1, 4, 1, 1, 6, 3, 3, 10, 9, 7, 1, 8, 10, 4, 1, 7
|1, 10, 1, 5, 4, 8, 8, 5, 5, 9, 7, 9, 1, 8, 4, 7, 8, 3, 5, 6, 2, 4, 0, 1, 10, 3, 10, 7, 8, 4, 10, 4, 10, 1, 10, 5, 1, 9, 8, 5, 6, 7, 6, 7, 9, 10, 9, 5, 8, 2
|7, 1, 8, 8, 9, 4, 9, 10, 1, 5, 6, 8, 8, 10, 9, 7, 10, 5, 3, 4, 10, 6, 5, 0, 6, 2, 6, 8, 2, 5, 5, 3, 4, 7, 6, 6, 2, 1, 1, 7, 8, 7, 9, 3, 6, 5, 2, 10, 2, 4
|3, 6, 6, 8, 9, 8, 4, 9, 2, 4, 3, 5, 8, 4, 1, 4, 9, 9, 3, 8, 2, 5, 10, 2, 0, 4, 5, 8, 5, 7, 5, 4, 4, 5, 1, 5, 2, 3, 2, 8, 4, 6, 9, 3, 8, 4, 1, 7, 5, 8
|9, 2, 7, 6, 1, 4, 9, 2, 5, 7, 2, 5, 2, 5, 5, 3, 6, 4, 8, 4, 8, 6, 10, 1, 6, 0, 6, 4, 3, 3, 4, 3, 7, 3, 3, 7, 8, 10, 7, 1, 2, 5, 4, 5, 8, 4, 7, 7, 2, 9
|2, 10, 9, 3, 1, 9, 7, 10, 8, 5, 10, 8, 4, 6, 9, 2, 3, 9, 4, 10, 9, 8, 7, 4, 6, 8, 0, 8, 7, 2, 2, 9, 7, 6, 9, 4, 3, 8, 4, 2, 8, 1, 1, 9, 4, 10, 2, 8, 8, 2
|1, 4, 4, 8, 8, 8, 3, 6, 7, 8, 1, 2, 10, 2, 2, 5, 4, 4, 8, 8, 2, 8, 5, 5, 2, 9, 9, 0, 4, 6, 10, 8, 3, 5, 2, 8, 4, 7, 2, 3, 4, 6, 3, 9, 6, 3, 8, 10, 3, 2
|9, 10, 1, 9, 8, 9, 6, 3, 3, 8, 9, 8, 7, 6, 6, 7, 10, 8, 5, 6, 6, 4, 2, 6, 9, 2, 10, 10, 0, 5, 9, 4, 3, 10, 9, 8, 3, 1, 5, 8, 1, 9, 7, 5, 4, 6, 10, 10, 7, 2
|9, 4, 6, 2, 2, 2, 2, 6, 6, 5, 5, 1, 6, 5, 6, 4, 7, 6, 4, 9, 2, 10, 9, 10, 2, 4, 1, 9, 1, 0, 5, 9, 3, 8, 10, 7, 4, 3, 10, 1, 8, 1, 7, 10, 5, 6, 1, 10, 10, 3
|4, 10, 3, 7, 3, 7, 2, 9, 10, 2, 2, 4, 3, 9, 5, 5, 9, 8, 3, 5, 2, 9, 7, 1, 4, 6, 2, 5, 4, 6, 0, 6, 1, 4, 5, 10, 8, 3, 2, 8, 7, 6, 10, 2, 5, 1, 7, 4, 10, 3
|6, 8, 3, 6, 2, 3, 5, 1, 10, 6, 8, 4, 6, 5, 7, 1, 6, 7, 1, 3, 7, 6, 10, 5, 5, 5, 10, 7, 2, 10, 9, 0, 1, 9, 2, 2, 8, 3, 6, 7, 3, 10, 5, 5, 7, 4, 6, 7, 7, 10
|3, 1, 5, 9, 6, 8, 5, 8, 4, 9, 3, 3, 6, 6, 7, 6, 1, 8, 7, 10, 2, 2, 8, 7, 4, 6, 3, 2, 6, 3, 4, 9, 0, 2, 7, 2, 7, 3, 3, 4, 3, 9, 3, 2, 4, 10, 1, 7, 2, 7
|10, 10, 4, 3, 5, 1, 7, 10, 6, 3, 5, 10, 3, 9, 7, 2, 5, 10, 4, 3, 10, 1, 7, 9, 1, 1, 5, 4, 3, 3, 7, 2, 5, 0, 10, 10, 1, 9, 2, 3, 6, 6, 7, 1, 9, 6, 5, 1, 1, 10
|5, 8, 7, 3, 2, 1, 5, 1, 1, 4, 9, 4, 6, 3, 9, 10, 1, 3, 4, 1, 9, 2, 10, 6, 10, 7, 6, 6, 10, 7, 5, 3, 2, 8, 0, 3, 3, 5, 8, 5, 2, 6, 2, 10, 5, 4, 3, 7, 1, 7
|10, 7, 7, 3, 7, 3, 2, 3, 2, 5, 7, 8, 1, 8, 10, 1, 1, 2, 7, 2, 6, 10, 9, 7, 10, 1, 7, 8, 9, 5, 3, 1, 10, 3, 5, 0, 6, 3, 5, 9, 4, 7, 3, 7, 7, 7, 1, 6, 9, 5
|8, 7, 8, 7, 10, 1, 3, 5, 4, 1, 8, 10, 8, 1, 7, 5, 1, 8, 5, 9, 3, 10, 9, 4, 7, 4, 2, 9, 1, 5, 8, 6, 8, 10, 1, 7, 0, 8, 8, 8, 1, 1, 3, 1, 1, 4, 9, 3, 8, 6
|10, 4, 1, 4, 3, 8, 1, 10, 3, 9, 4, 3, 5, 10, 5, 10, 10, 2, 6, 10, 10, 1, 1, 4, 7, 7, 2, 1, 4, 8, 2, 9, 4, 7, 1, 7, 6, 0, 7, 10, 2, 1, 8, 5, 2, 7, 6, 7, 1, 9
|10, 6, 5, 8, 7, 6, 9, 5, 6, 8, 9, 9, 9, 1, 3, 4, 7, 9, 5, 7, 6, 1, 1, 5, 1, 1, 5, 10, 3, 6, 9, 3, 4, 4, 9, 10, 9, 1, 0, 10, 7, 5, 4, 10, 8, 6, 2, 10, 4, 5
|5, 9, 1, 7, 9, 9, 5, 9, 5, 4, 10, 5, 8, 2, 7, 1, 5, 8, 4, 7, 1, 7, 7, 5, 2, 4, 9, 5, 7, 5, 8, 4, 1, 7, 7, 8, 4, 7, 4, 0, 4, 1, 2, 1, 5, 7, 9, 1, 10, 2
|9, 5, 7, 7, 6, 7, 10, 7, 1, 3, 2, 8, 4, 1, 8, 2, 6, 2, 10, 3, 5, 10, 6, 4, 10, 7, 7, 5, 10, 2, 10, 6, 1, 7, 10, 9, 2, 8, 3, 5, 0, 3, 10, 4, 4, 9, 9, 5, 10, 6
|8, 9, 3, 5, 10, 8, 3, 9, 1, 10, 1, 9, 7, 7, 3, 1, 10, 9, 1, 3, 5, 10, 2, 8, 10, 5, 4, 10, 9, 4, 7, 5, 2, 7, 10, 1, 8, 5, 1, 4, 4, 0, 2, 4, 6, 4, 8, 10, 9, 3
|5, 2, 1, 2, 9, 8, 8, 5, 4, 8, 1, 2, 3, 9, 2, 5, 9, 5, 6, 9, 1, 3, 2, 4, 1, 9, 4, 6, 1, 5, 9, 6, 1, 6, 8, 8, 8, 6, 7, 9, 8, 7, 0, 10, 8, 3, 3, 4, 2, 10
|1, 4, 8, 7, 8, 10, 4, 7, 7, 4, 2, 1, 3, 4, 1, 3, 5, 10, 3, 5, 10, 6, 5, 7, 10, 3, 6, 2, 5, 2, 8, 7, 2, 10, 4, 7, 7, 7, 5, 4, 9, 2, 5, 0, 3, 1, 3, 7, 3, 6
|6, 10, 4, 6, 7, 8, 1, 4, 9, 10, 5, 1, 3, 7, 5, 5, 1, 9, 2, 1, 8, 8, 3, 1, 6, 2, 9, 6, 9, 9, 8, 3, 8, 2, 5, 8, 3, 9, 3, 4, 10, 10, 7, 3, 0, 9, 6, 5, 3, 4
|4, 1, 1, 4, 8, 2, 3, 5, 4, 4, 5, 2, 6, 6, 2, 4, 2, 10, 9, 7, 3, 6, 9, 6, 10, 10, 8, 1, 10, 8, 5, 3, 8, 10, 3, 9, 8, 3, 8, 10, 4, 9, 2, 5, 3, 0, 5, 9, 5, 4
|2, 9, 7, 10, 9, 1, 2, 9, 3, 8, 1, 4, 4, 10, 9, 1, 4, 4, 2, 8, 1, 9, 9, 7, 8, 7, 5, 2, 1, 6, 10, 5, 1, 8, 10, 1, 4, 4, 7, 1, 7, 3, 3, 7, 4, 10, 0, 1, 2, 5
|5, 9, 4, 6, 5, 5, 7, 5, 9, 5, 5, 9, 8, 2, 5, 5, 2, 9, 7, 4, 5, 5, 8, 5, 2, 1, 2, 7, 7, 2, 9, 10, 4, 2, 9, 6, 9, 4, 8, 4, 10, 8, 2, 9, 10, 10, 9, 0, 3, 5
|3, 10, 8, 7, 5, 5, 9, 2, 5, 8, 3, 8, 1, 1, 7, 4, 8, 3, 1, 4, 7, 4, 3, 9, 1, 8, 5, 9, 9, 7, 2, 6, 6, 10, 1, 6, 7, 3, 8, 1, 6, 10, 10, 1, 1, 5, 8, 2, 0, 2
|6, 6, 8, 8, 8, 10, 8, 10, 8, 3, 4, 5, 8, 4, 10, 6, 8, 10, 2, 8, 10, 7, 10, 3, 9, 9, 5, 9, 5, 8, 8, 10, 1, 1, 8, 4, 2, 2, 9, 10, 4, 5, 4, 1, 4, 5, 3, 3, 2, 0
|];
TimeWindows = [| 7, 504
|10, 582
|6, 552
|3, 531
|8, 538
|7, 520
|7, 514
|7, 585
|10, 599
|5, 585
|1, 549
|7, 531
|3, 526
|1, 553
|8, 562
|3, 575
|6, 534
|1, 574
|5, 554
|6, 577
|7, 532
|6, 605
|9, 531
|8, 509
|9, 529
|2, 532
|2, 559
|4, 584
|6, 535
|8, 574
|9, 580
|7, 571
|7, 511
|7, 596
|5, 607
|4, 536
|5, 593
|1, 575
|2, 565
|9, 525
|];
The key of this seems to be the timeout. With a higher timeout both approaches should always give the same result. But that doesn't really explain why MiniZincIDE and MiniZinc-Python give different results, but it could be just some fluke.
I tested the model with the Chuffed solver (+ free search flag) and it took 3.4s:
...
----------
obj = 73
----------
==========
Google OR-tools took about the same time (with 12 threads it took 0.9s).
As mentioned in
Placing array of rectangles inside a given area using Minizinc , one might have to experiment with different solvers/search strategies and variants of the model to get faster times.
For this model it seems to suffice to simply change the solver (if that is a acceptable action).
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l have three vectors (numpy arrays), vector_1, vector_2, vector_3 as follow : Dimension(vector1)=(200,2048) Dimension(vector2)=(200,8192) Dimension(vector3)=(200,32768) l would like to append these vectors to get vector_4 : Dimension(vector4)= (200,2048+8192+32768)= (200, 43008) Add respectively vector1 then vector2 then vector3 l tries the following : vector4=numpy.concatenate((vector1,vector2,vector3),axis=0) ValueError: all the input array dimensions except for the concatenation axis must match exactly and vector4=numpy.append(vector4,[vector1,vector2,vectors3],axis=0) TypeError: append() missing 1 required positional argument: 'values'
I believe you are looking for numpy.hstack. >>> import numpy as np >>> a = np.arange(4).reshape(2,2) >>> b = np.arange(6).reshape(2,3) >>> c = np.arange(8).reshape(2,4) >>> a array([[0, 1], [2, 3]]) >>> b array([[0, 1, 2], [3, 4, 5]]) >>> c array([[0, 1, 2, 3], [4, 5, 6, 7]]) >>> np.hstack((a,b,c)) array([[0, 1, 0, 1, 2, 0, 1, 2, 3], [2, 3, 3, 4, 5, 4, 5, 6, 7]])
The error message is pretty much telling you exactly what is the problem: ValueError: all the input array dimensions except for the concatenation axis must match exactly But you are doing the opposite, the concatenation axis dimensions match exactly but the others don't. Consider: In [3]: arr1 = np.random.randint(0,10,(20, 5)) In [4]: arr2 = np.random.randint(0,10,(20, 3)) In [5]: arr3 = np.random.randint(0,10,(20, 11)) Note the dimensions. Just give it the correct axis. So use the second rather than the first: In [8]: arr1.shape, arr2.shape, arr3.shape Out[8]: ((20, 5), (20, 3), (20, 11)) In [9]: np.concatenate((arr1, arr2, arr3), axis=1) Out[9]: array([[3, 1, 4, 7, 3, 6, 1, 1, 6, 7, 4, 6, 8, 6, 2, 8, 2, 5, 0], [4, 2, 2, 1, 7, 8, 0, 7, 2, 2, 3, 9, 8, 0, 7, 3, 5, 9, 6], [2, 8, 9, 8, 5, 3, 5, 8, 5, 2, 4, 1, 2, 0, 3, 2, 9, 1, 0], [6, 7, 3, 5, 6, 8, 3, 8, 4, 8, 1, 5, 4, 4, 6, 4, 0, 3, 4], [3, 5, 8, 8, 7, 7, 4, 8, 7, 3, 8, 7, 0, 2, 8, 9, 1, 9, 0], [5, 4, 8, 3, 7, 8, 3, 2, 7, 8, 2, 4, 8, 0, 6, 9, 2, 0, 3], [0, 0, 1, 8, 6, 4, 4, 4, 2, 8, 4, 1, 4, 1, 3, 1, 5, 5, 1], [1, 6, 3, 3, 9, 2, 3, 4, 9, 2, 6, 1, 4, 1, 5, 6, 0, 1, 9], [4, 5, 4, 7, 1, 4, 0, 8, 8, 1, 6, 0, 4, 6, 3, 1, 2, 5, 2], [6, 4, 3, 2, 9, 4, 1, 7, 7, 0, 0, 5, 9, 3, 7, 4, 5, 6, 1], [7, 7, 0, 4, 1, 9, 9, 1, 0, 1, 8, 3, 6, 0, 5, 1, 4, 0, 7], [7, 9, 0, 4, 0, 5, 5, 9, 8, 9, 9, 7, 8, 8, 2, 6, 2, 3, 1], [4, 1, 6, 5, 4, 5, 6, 7, 9, 2, 5, 8, 6, 6, 6, 8, 2, 3, 1], [7, 7, 8, 5, 0, 8, 5, 6, 4, 4, 3, 5, 9, 8, 7, 9, 8, 8, 1], [3, 9, 3, 6, 3, 2, 2, 4, 0, 1, 0, 4, 3, 0, 1, 3, 4, 1, 3], [5, 1, 9, 7, 1, 8, 3, 9, 4, 7, 6, 7, 4, 7, 0, 1, 2, 8, 7], [6, 3, 8, 0, 6, 2, 1, 8, 1, 0, 0, 3, 7, 2, 1, 5, 7, 0, 7], [5, 4, 7, 5, 5, 8, 3, 2, 6, 1, 0, 4, 6, 9, 7, 3, 9, 2, 5], [1, 4, 8, 5, 7, 2, 0, 2, 6, 2, 6, 5, 5, 4, 6, 1, 8, 8, 1], [4, 4, 5, 6, 2, 6, 0, 5, 1, 8, 4, 5, 8, 9, 2, 1, 0, 4, 2]]) In [10]: np.concatenate((arr1, arr2, arr3), axis=1).shape Out[10]: (20, 19)
python: FOR loop, Iterating assignment not assigning correct value
I am making a list, with a list nested inside. This second list I need to iterate through, and assign a value to a position. So I wrote this matrix=[] list=[0,1,2,3,4,5,6,7,8,9] def board(): for x in range(10): for y in range(10): matrix.append([[x,y],1]) #A grid is made, with a spare element for i in range(100): matrix[i][1]=list #The grid is two elements, co-ords... #and a list of attributes board() for i in range(100): matrix[i][2][0]=i #The first attribute,(in 2nd of2elements), print(matrix) ##SHOULD be its own position All variations of this code result in the same thing: Error or the number "99" being placed in EVERY INSTANCE of that location. That is to say my final FOR loop seems to be assigning "99" NOT i... I have tried several variations of this (generating the numbers inside the FOR loop was my preference, alas) I have spent about 6 hours staring at this. All my logic tells me that the computer should KNOW that I want the first element, of that second element, to be a count 0,1,2... I know this can't be because of a limit on the language, so tell me what I am not seeing.
matrix[i][1]=list When you do this the same array is being assigned in the matrix array. Hence if you change one item, all the items get changed. Instead assign a copy of the list like this: matrix[i][1] = list[:] As pointed out by #Bakuriu , in python 3 you can use list.copy() method. In Python 2 you can use the copy module to copy containers with l2 = copy.copy(l1) Also, you should change the name of the variable 'list' as 'list' is an inbuilt type in python.
You should replace matrix[i][2][0]=i assignement as it raises an IndexError to: for i in range(100): matrix[i][1][0]=i #The first attribute,(in 2nd of2elements), print(matrix) ##SHOULD be its own position
Lists are faster in for loop, but here You have solution with dicts: from pprint import pprint as ppr matrix={} list=[0,1,2,3,4,5,6,7,8,9] def board(): for x in range(10): for y in range(10): matrix[(x,y)]=1 for k in matrix.keys(): matrix[k]=list board() ppr(matrix) for k in matrix.iterkeys(): v=matrix[k][:] v[2]=k[0]*10+k[1] matrix[k]=v ppr(matrix) Input: {(0, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (1, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (2, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (3, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (4, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (5, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (6, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (7, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (8, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 0): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 1): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 3): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 4): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 5): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 6): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 7): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 8): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (9, 9): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]} Output: {(0, 0): [0, 1, 0, 3, 4, 5, 6, 7, 8, 9], (0, 1): [0, 1, 1, 3, 4, 5, 6, 7, 8, 9], (0, 2): [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], (0, 3): [0, 1, 3, 3, 4, 5, 6, 7, 8, 9], (0, 4): [0, 1, 4, 3, 4, 5, 6, 7, 8, 9], (0, 5): [0, 1, 5, 3, 4, 5, 6, 7, 8, 9], (0, 6): [0, 1, 6, 3, 4, 5, 6, 7, 8, 9], (0, 7): [0, 1, 7, 3, 4, 5, 6, 7, 8, 9], (0, 8): [0, 1, 8, 3, 4, 5, 6, 7, 8, 9], (0, 9): [0, 1, 9, 3, 4, 5, 6, 7, 8, 9], (1, 0): [0, 1, 10, 3, 4, 5, 6, 7, 8, 9], (1, 1): [0, 1, 11, 3, 4, 5, 6, 7, 8, 9], (1, 2): [0, 1, 12, 3, 4, 5, 6, 7, 8, 9], (1, 3): [0, 1, 13, 3, 4, 5, 6, 7, 8, 9], (1, 4): [0, 1, 14, 3, 4, 5, 6, 7, 8, 9], (1, 5): [0, 1, 15, 3, 4, 5, 6, 7, 8, 9], (1, 6): [0, 1, 16, 3, 4, 5, 6, 7, 8, 9], (1, 7): [0, 1, 17, 3, 4, 5, 6, 7, 8, 9], (1, 8): [0, 1, 18, 3, 4, 5, 6, 7, 8, 9], (1, 9): [0, 1, 19, 3, 4, 5, 6, 7, 8, 9], (2, 0): [0, 1, 20, 3, 4, 5, 6, 7, 8, 9], (2, 1): [0, 1, 21, 3, 4, 5, 6, 7, 8, 9], (2, 2): [0, 1, 22, 3, 4, 5, 6, 7, 8, 9], (2, 3): [0, 1, 23, 3, 4, 5, 6, 7, 8, 9], (2, 4): [0, 1, 24, 3, 4, 5, 6, 7, 8, 9], (2, 5): [0, 1, 25, 3, 4, 5, 6, 7, 8, 9], (2, 6): [0, 1, 26, 3, 4, 5, 6, 7, 8, 9], (2, 7): [0, 1, 27, 3, 4, 5, 6, 7, 8, 9], (2, 8): [0, 1, 28, 3, 4, 5, 6, 7, 8, 9], (2, 9): [0, 1, 29, 3, 4, 5, 6, 7, 8, 9], (3, 0): [0, 1, 30, 3, 4, 5, 6, 7, 8, 9], (3, 1): [0, 1, 31, 3, 4, 5, 6, 7, 8, 9], (3, 2): [0, 1, 32, 3, 4, 5, 6, 7, 8, 9], (3, 3): [0, 1, 33, 3, 4, 5, 6, 7, 8, 9], (3, 4): [0, 1, 34, 3, 4, 5, 6, 7, 8, 9], (3, 5): [0, 1, 35, 3, 4, 5, 6, 7, 8, 9], (3, 6): [0, 1, 36, 3, 4, 5, 6, 7, 8, 9], (3, 7): [0, 1, 37, 3, 4, 5, 6, 7, 8, 9], (3, 8): [0, 1, 38, 3, 4, 5, 6, 7, 8, 9], (3, 9): [0, 1, 39, 3, 4, 5, 6, 7, 8, 9], (4, 0): [0, 1, 40, 3, 4, 5, 6, 7, 8, 9], (4, 1): [0, 1, 41, 3, 4, 5, 6, 7, 8, 9], (4, 2): [0, 1, 42, 3, 4, 5, 6, 7, 8, 9], (4, 3): [0, 1, 43, 3, 4, 5, 6, 7, 8, 9], (4, 4): [0, 1, 44, 3, 4, 5, 6, 7, 8, 9], (4, 5): [0, 1, 45, 3, 4, 5, 6, 7, 8, 9], (4, 6): [0, 1, 46, 3, 4, 5, 6, 7, 8, 9], (4, 7): [0, 1, 47, 3, 4, 5, 6, 7, 8, 9], (4, 8): [0, 1, 48, 3, 4, 5, 6, 7, 8, 9], (4, 9): [0, 1, 49, 3, 4, 5, 6, 7, 8, 9], (5, 0): [0, 1, 50, 3, 4, 5, 6, 7, 8, 9], (5, 1): [0, 1, 51, 3, 4, 5, 6, 7, 8, 9], (5, 2): [0, 1, 52, 3, 4, 5, 6, 7, 8, 9], (5, 3): [0, 1, 53, 3, 4, 5, 6, 7, 8, 9], (5, 4): [0, 1, 54, 3, 4, 5, 6, 7, 8, 9], (5, 5): [0, 1, 55, 3, 4, 5, 6, 7, 8, 9], (5, 6): [0, 1, 56, 3, 4, 5, 6, 7, 8, 9], (5, 7): [0, 1, 57, 3, 4, 5, 6, 7, 8, 9], (5, 8): [0, 1, 58, 3, 4, 5, 6, 7, 8, 9], (5, 9): [0, 1, 59, 3, 4, 5, 6, 7, 8, 9], (6, 0): [0, 1, 60, 3, 4, 5, 6, 7, 8, 9], (6, 1): [0, 1, 61, 3, 4, 5, 6, 7, 8, 9], (6, 2): [0, 1, 62, 3, 4, 5, 6, 7, 8, 9], (6, 3): [0, 1, 63, 3, 4, 5, 6, 7, 8, 9], (6, 4): [0, 1, 64, 3, 4, 5, 6, 7, 8, 9], (6, 5): [0, 1, 65, 3, 4, 5, 6, 7, 8, 9], (6, 6): [0, 1, 66, 3, 4, 5, 6, 7, 8, 9], (6, 7): [0, 1, 67, 3, 4, 5, 6, 7, 8, 9], (6, 8): [0, 1, 68, 3, 4, 5, 6, 7, 8, 9], (6, 9): [0, 1, 69, 3, 4, 5, 6, 7, 8, 9], (7, 0): [0, 1, 70, 3, 4, 5, 6, 7, 8, 9], (7, 1): [0, 1, 71, 3, 4, 5, 6, 7, 8, 9], (7, 2): [0, 1, 72, 3, 4, 5, 6, 7, 8, 9], (7, 3): [0, 1, 73, 3, 4, 5, 6, 7, 8, 9], (7, 4): [0, 1, 74, 3, 4, 5, 6, 7, 8, 9], (7, 5): [0, 1, 75, 3, 4, 5, 6, 7, 8, 9], (7, 6): [0, 1, 76, 3, 4, 5, 6, 7, 8, 9], (7, 7): [0, 1, 77, 3, 4, 5, 6, 7, 8, 9], (7, 8): [0, 1, 78, 3, 4, 5, 6, 7, 8, 9], (7, 9): [0, 1, 79, 3, 4, 5, 6, 7, 8, 9], (8, 0): [0, 1, 80, 3, 4, 5, 6, 7, 8, 9], (8, 1): [0, 1, 81, 3, 4, 5, 6, 7, 8, 9], (8, 2): [0, 1, 82, 3, 4, 5, 6, 7, 8, 9], (8, 3): [0, 1, 83, 3, 4, 5, 6, 7, 8, 9], (8, 4): [0, 1, 84, 3, 4, 5, 6, 7, 8, 9], (8, 5): [0, 1, 85, 3, 4, 5, 6, 7, 8, 9], (8, 6): [0, 1, 86, 3, 4, 5, 6, 7, 8, 9], (8, 7): [0, 1, 87, 3, 4, 5, 6, 7, 8, 9], (8, 8): [0, 1, 88, 3, 4, 5, 6, 7, 8, 9], (8, 9): [0, 1, 89, 3, 4, 5, 6, 7, 8, 9], (9, 0): [0, 1, 90, 3, 4, 5, 6, 7, 8, 9], (9, 1): [0, 1, 91, 3, 4, 5, 6, 7, 8, 9], (9, 2): [0, 1, 92, 3, 4, 5, 6, 7, 8, 9], (9, 3): [0, 1, 93, 3, 4, 5, 6, 7, 8, 9], (9, 4): [0, 1, 94, 3, 4, 5, 6, 7, 8, 9], (9, 5): [0, 1, 95, 3, 4, 5, 6, 7, 8, 9], (9, 6): [0, 1, 96, 3, 4, 5, 6, 7, 8, 9], (9, 7): [0, 1, 97, 3, 4, 5, 6, 7, 8, 9], (9, 8): [0, 1, 98, 3, 4, 5, 6, 7, 8, 9], (9, 9): [0, 1, 99, 3, 4, 5, 6, 7, 8, 9]} You could use numpy here, with fast indexing (faster is cython memoryview so look at it too): matrix=np.zeros((100,10),dtype=int) list=[0,1,2,3,4,5,6,7,8,9] def board(matrix): for x in range(10): for y in range(10): matrix[x*10+y]=1 #but here You populate whole sub-array of shape (10) with 1, so it will be: [1,1,1,1...,1] print matrix for k in range(matrix.shape[0]): matrix[k]=list board(matrix) ppr(matrix) for k in range(matrix.shape[0]): matrix[k,2]=k ppr(matrix)
How can iterate throught a dictionary in a list in python
This is an output from traversing through different folders in a directory: r= [{'s.data': [22, 10, 21, 2, 3, 3, 4, 4, 4], 'd.data': [1, 5, 3,67,8,4, 9, 0, 2], 'q.data': [2, 3, 4, 5, 6, 3, 4, 2, 32], 't.data': [32, 21, 9, 2, 13, 5, 4, 9, 7], 'k.data': [3, 7, 2, 5, 68, 90, 23, 11, 22]}, {'s.data': [9, 8, 7, 6, 5, 4, 3, 2, 1], 'd.data': [2, 6, 3, 8, 9, 0, 3, 2, 5], 'q.data': [1, 2, 3, 4, 5, 6, 7, 8, 9], 't.data': [0, 8, 9, 7, 5, 6, 4, 2, 3], 'k.data': [4, 3, 2, 6, 7, 8, 9, 0, 1]}, {'s.data': [4, 3, 6, 4, 7, 2, 8, 1, 9], 'd.data': [6, 4, 3, 5, 6, 7, 8, 9, 0], 'q.data': [23, 2, 3, 6, 8, 4, 5, 0, 8], 't.data': [2, 1, 3, 4, 5, 11, 2, 6, 7], 'k.data': [1, 0, 2, 9, 3, 8, 4, 7, 4]}, {'s.data': [1, 9, 7, 0, 2, 4, 2, 3, 5], 'd.data': [4, 3, 7, 9, 2, 3, 0, 9, 10], 'q.data': [0, 23, 4, 2, 4, 6, 8, 3, 0], 't.data': [4, 1, 7, 4, 0, 8, 9, 9, 0], 'k.data': [9, 2, 6, 1, 2, 3, 5, 6, 9]}, {'s.data': [22, 10, 21, 2, 3, 3, 4, 4, 4], 'd.data': [5, 7, 4, 5, 8, 9, 0, 2, 3], 'q.data': [3, 2, 4, 5, 6, 7, 8, 9, 1], 't.data': [2, 3, 1, 4, 5, 6, 7, 8, 0], 'k.data': [3, 2, 5, 6, 7, 4, 5, 6, 2]}] How can I print only the values like the following without the keys as follows: [[22, 10, 21, 2, 3, 3, 4, 4, 4], [9, 8, 7, 6, 5, 4, 3, 2, 1], [4, 3, 6, 4, 7, 2, 8, 1, 9], [1, 9, 7, 0, 2, 4, 2, 3, 5]] Any help will be appreciated!
Something like this should do the trick, if you don't need a specific ordering across the s.data, k.data, etc keys. print [x.values() for x in r] Alternativelym if you care only about s.data or any other specific key, you can do k = 's.data' print [x[k] for x in r]
You apparently want only the values for the key 's.data' in each of the dictionaries. You can do that as follows: [d['s.data'] for d in r]
Combining multiple numpy arrays into one
I have this O/P as shown in the below pic My O/P consists of around 100+ numpy arrays like the one shown above. I'm trying to combine all these 100+ numpy arrays into an single numpy array for further data processing. Any ideas on how to get this done???? I'm using python V3.4
You can use hstack and vstack: In [29]: hstack((arange(10) for _ in range(10))) Out[29]: array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9]) In [30]: vstack((arange(10) for _ in range(10))) Out[30]: array([[0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]])
Numpy Routine(s) to create a regular grid inside a 2d array
I am trying to write a function that would create a regular grid of 5 pixels by 5 pixels inside a 2d array. I was hoping some combination of numpy.arange and numpy.repeat might do it, but so far I haven't had any luck because numpy.repeat will just repeat along the same row. Here is an example: Let's say I want a 5x5 grid inside a 2d array of shape (20, 15). It should look like: array([[ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 9, 9, 9, 9, 9,10,10,10,10,10,11,11,11,11,11], [ 9, 9, 9, 9, 9,10,10,10,10,10,11,11,11,11,11], [ 9, 9, 9, 9, 9,10,10,10,10,10,11,11,11,11,11], [ 9, 9, 9, 9, 9,10,10,10,10,10,11,11,11,11,11], [ 9, 9, 9, 9, 9,10,10,10,10,10,11,11,11,11,11]]) I realize I could simply use a loop and slicing to accomplish this, but I could be applying this to very large arrays and I worry that the performance of that would be too slow or impractical. Can anyone recommend a method to accomplish this? Thanks in advance. UPDATE: All the answers provided seem to work well. Can anyone tell me which will be the most efficient to use for large arrays? By large array I mean it could be 100000 x 100000 or more with 15 x 15 grid cell sizes.
Broadcasting is the answer here: m, n, d = 20, 15, 5 arr = np.empty((m, n), dtype=np.int) arr_view = arr.reshape(m // d, d, n // d, d) vals = np.arange(m // d * n // d).reshape(m // d, 1, n // d, 1) arr_view[:] = vals >>> arr array([[ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8], [ 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11], [ 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11], [ 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11], [ 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11], [ 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11]])
Similar to Jaime's answer: np.repeat(np.arange(0, 10, 3), 4)[..., None] + np.repeat(np.arange(3), 5)[None, ...]
kron will do this expansion (as Brionius also suggested in the comments): xi, xj, ni, nj = 5, 5, 4, 3 r = np.kron(np.arange(ni*nj).reshape((ni,nj)), np.ones((xi, xj))) Although I haven't tested it, I assume it's less efficient than the broadcasting approach, but a bit more concise and easier to understand (I hope). It's likely less efficient because: 1) it requires the array of ones, 2) it does xi*xj multiplications by 1, and 3) it does a bunch of concats.