diff --git a/galsec.py b/galsec.py
index 5e0e538..c3db466 100644
--- a/galsec.py
+++ b/galsec.py
@@ -7,6 +7,8 @@ import numpy as np
 from astropy.table import QTable, hstack
 from astropy import units as u
 from astropy.units.quantity import Quantity
+from scipy.interpolate import griddata
+from scipy.fft import fftn
 
 
 def vect_r(position: np.array, vector: np.array) -> np.array:
@@ -136,6 +138,66 @@ def aggregate(
     return binned_data
 
 
+def get_bouncing_box_mask(
+    data: QTable, r: Quantity[u.kpc], phi: Quantity[u.rad], size: Quantity[u.kpc]
+):
+    x = r * np.cos(phi)
+    y = r * np.sin(phi)
+    norm_inf = np.maximum(
+        np.abs(data["position"][:, 0] - x), np.abs(data["position"][:, 1] - y)
+    )
+    mask = (norm_inf < size / 2) & (np.abs(data["position"][:, 2]) < size / 2)
+    return mask
+
+
+def regrid(
+    position: Quantity,
+    value: Quantity,
+    resolution: Quantity[u.pc],
+):
+    min_x, max_x = position[:, 0].min(), position[:, 0].max()
+    min_y, max_y = position[:, 1].min(), position[:, 1].max()
+    min_z, max_z = position[:, 2].min(), position[:, 2].max()
+    size = max([max_x - min_x, max_y - min_y, max_z - min_z])
+
+    nb_points = int(np.ceil(((size / resolution).to(u.dimensionless_unscaled).value)))
+    gx, gy, gz = np.mgrid[
+        min_x.value : max_x.value : nb_points * 1j,
+        min_y.value : max_y.value : nb_points * 1j,
+        min_z.value : max_z.value : nb_points * 1j,
+    ]
+
+    grid = griddata(
+        position.value,
+        value.value,
+        (gx, gy, gz),
+        method="nearest",
+    )
+
+    import matplotlib.pyplot as plt
+
+    plt.imshow(
+        grid[:, :, len(grid) // 2].T,
+        origin="lower",
+        extent=[min_x.value, max_x.value, min_y.value, max_y.value],
+    )
+    plt.show()
+
+    return (
+        grid,
+        (gx, gy, gz),
+    )
+
+def fft(
+    position: Quantity,
+    value: Quantity,
+    resolution: Quantity[u.pc],
+    ):
+    
+    grid, (gx, gy, gz) =  regrid(position, value, resolution)
+        
+    fftn(grid, overwrite_x=True)
+
 class Galsec:
     """
     Galactic sector extractor
@@ -258,6 +320,8 @@ class Galsec:
         delta_l: Quantity[u.kpc] = u.kpc,
         rmin: Quantity[u.kpc] = 1 * u.kpc,
         rmax: Quantity[u.kpc] = 12 * u.kpc,
+        zmin: Quantity[u.kpc] = -0.5 * u.kpc,
+        zmax: Quantity[u.kpc] = 0.5 * u.kpc,
     ):
         """Compute the aggration of quantities in sectors bins
 
@@ -274,7 +338,7 @@ class Galsec:
         """
 
         self.sector_binning(delta_r, delta_l)
-        grouped_data = {}
+        self.grouped_data = {}
         self.sectors = {}
 
         for fluid in self.fluids:
@@ -283,15 +347,20 @@ class Galsec:
             else:
                 extensive_fields = ["mass", "ek"]
             filtered_data = self.data[fluid][
-                np.logical_and(
-                    self.data[fluid]["r"] > rmin, self.data[fluid]["r"] < rmax
-                )
+                (self.data[fluid]["r"] > rmin)
+                & (self.data[fluid]["r"] < rmax)
+                & (self.data[fluid]["position"][:, 2] > zmin)
+                & (self.data[fluid]["position"][:, 2] < zmax)
             ]
-            grouped_data[fluid] = filtered_data.group_by(["r_bin", "phi_bin"])
+            self.grouped_data[fluid] = filtered_data.group_by(["r_bin", "phi_bin"])
             self.sectors[fluid] = hstack(
                 [
-                    grouped_data[fluid]["r_bin", "phi_bin"].groups.aggregate(np.fmin),
-                    aggregate(grouped_data[fluid], extensive_fields=extensive_fields),
+                    self.grouped_data[fluid]["r_bin", "phi_bin"].groups.aggregate(
+                        np.fmin
+                    ),
+                    aggregate(
+                        self.grouped_data[fluid], extensive_fields=extensive_fields
+                    ),
                 ]
             )
             self.sectors[fluid].rename_column("r_bin", "r")
@@ -300,7 +369,7 @@ class Galsec:
         self.sectors["stars"]["sfr"] = (
             np.zeros(len(self.sectors["stars"]["mass"])) * u.Msun / u.year
         )
-        for i, group in enumerate(grouped_data["stars"].groups):
+        for i, group in enumerate(self.grouped_data["stars"].groups):
             self.sectors["stars"]["sfr"][i] = get_sfr(group, self.time)
 
         self.sectors["stars"]["sfr"][i] = get_sfr(group, self.time)
@@ -310,6 +379,8 @@ class Galsec:
         delta_r: Quantity[u.kpc] = u.kpc,
         rmin: Quantity[u.kpc] = 1 * u.kpc,
         rmax: Quantity[u.kpc] = 12 * u.kpc,
+        zmin: Quantity[u.kpc] = -0.5 * u.kpc,
+        zmax: Quantity[u.kpc] = 0.5 * u.kpc,
     ):
         """Compute the aggration of quantities in radial bins
 
@@ -333,9 +404,10 @@ class Galsec:
             else:
                 extensive_fields = ["mass", "ek"]
             filtered_data = self.data[fluid][
-                np.logical_and(
-                    self.data[fluid]["r"] > rmin, self.data[fluid]["r"] < rmax
-                )
+                (self.data[fluid]["r"] > rmin)
+                & (self.data[fluid]["r"] < rmax)
+                & (self.data[fluid]["z"] > zmin)
+                & (self.data[fluid]["z"] < zmax)
             ]
             grouped_data[fluid] = filtered_data.group_by(["r_bin"])
             self.rings[fluid] = hstack(
diff --git a/galsec_plot.py b/galsec_plot.py
index 886c74a..68d12c7 100644
--- a/galsec_plot.py
+++ b/galsec_plot.py
@@ -50,6 +50,6 @@ def plot_radial(table: QTable):
         P[0, -1] = P[0, 0]
         P[1, -1] = P[1, 0]
 
-        pc = ax.pcolormesh(P, R, C, cmap="tab20c") #, vmin=6, vmax=9)
+        pc = ax.pcolormesh(P, R, C, cmap="tab20c")  # , vmin=6, vmax=9)
         print(P, R, C)
-    #fig.colorbar(pc)
+    # fig.colorbar(pc)