diff --git a/bin/bootstrapQMLE.py b/bin/bootstrapQMLE.py
index 5e970cd..84d1900 100755
--- a/bin/bootstrapQMLE.py
+++ b/bin/bootstrapQMLE.py
@@ -6,18 +6,18 @@
 
 import argparse
 import sys
-from os.path import join as ospath_join, \
-    getsize as ospath_getsize, dirname as ospath_dir
-
-import glob
+from os.path import (
+    join as ospath_join,
+    getsize as ospath_getsize,
+    dirname as ospath_dir
+)
 import struct
-import time
 import logging
 
 import numpy as np
 from numba import njit
+from scipy.linalg import cho_factor, cho_solve
 
-from qsotools.utils import Progress
 
 def getNumbersfromBootfile(fname):
     filesize = ospath_getsize(fname)
@@ -27,34 +27,38 @@ def getNumbersfromBootfile(fname):
         Nz = int(struct.unpack('i', f.read(struct.calcsize('i')))[0])
         Nd = int(struct.unpack('i', f.read(struct.calcsize('i')))[0])
 
-    total_nkz = Nk*Nz
+    total_nkz = Nk * Nz
 
     if Nd == 3:
-        cf_size = 3*total_nkz - Nk - 1
+        cf_size = 3 * total_nkz - Nk - 1
     else:
-        cf_size = int(total_nkz*Nd - (Nd*(Nd-1))/2)
+        cf_size = int(total_nkz * Nd - (Nd * (Nd - 1)) / 2)
 
-    elems_count   = cf_size + total_nkz;
-    one_data_size = struct.calcsize('d'*elems_count)
+    elems_count = cf_size + total_nkz
+    one_data_size = struct.calcsize('d' * elems_count)
 
-    nspec = int((filesize-3*struct.calcsize('i'))/one_data_size)
+    nspec = int((filesize - 3 * struct.calcsize('i')) / one_data_size)
 
     return Nk, Nz, Nd, total_nkz, elems_count, nspec
 
 # Returns data
 # First Nkz is power, rest is fisher that needs to be reshaped
+
+
 def readBootFile(fname, N):
     dt = np.dtype(('f8', N))
 
     with open(fname, "rb") as bootfile:
-        spectra = np.fromfile(bootfile, offset=3*struct.calcsize('i'), dtype=dt)
+        spectra = np.fromfile(
+            bootfile, offset=3 * struct.calcsize('i'), dtype=dt)
 
     return spectra
 
+
 @njit("Tuple((f8[:, :], f8[:, :, :]))(f8[:, :], i8, i8, i8, i8)")
 def getPSandFisher(v, nk, nd, total_nkz, rem_nz=0):
     nboot = v.shape[0]
-    newsize = total_nkz-rem_nz*nk
+    newsize = total_nkz - rem_nz * nk
     power = v[:, :newsize]
     fisher = np.zeros((nboot, newsize, newsize))
 
@@ -67,30 +71,47 @@ def getPSandFisher(v, nk, nd, total_nkz, rem_nz=0):
 
     fari = 0
     for did in diag_idx:
-        for jj in range(newsize-did):
-            fisher[:, jj, jj+did] = farr[:, fari+jj]
-            fisher[:, jj+did, jj] = farr[:, fari+jj]
+        for jj in range(newsize - did):
+            fisher[:, jj, jj + did] = farr[:, fari + jj]
+            fisher[:, jj + did, jj] = farr[:, fari + jj]
 
-        fari += total_nkz-did
+        fari += total_nkz - did
 
     for jj in range(newsize):
-        fisher[:, jj, jj] = np.where(fisher[:, jj, jj]==0, 1, fisher[:, jj, jj])
+        fisher[:, jj, jj] = np.where(
+            fisher[:, jj, jj] == 0, 1, fisher[:, jj, jj])
 
     return power, fisher
 
+
 @njit("i8[:, :](i8[:, :])")
 def getCounts(booted_indices):
     bootnum, no_spectra = booted_indices.shape
-   
+
     counts = np.empty_like(booted_indices)
     for b in range(bootnum):
         counts[b] = np.bincount(booted_indices[b], minlength=no_spectra)
 
     return counts
 
-def getOneSliceBoot(spectra, booted_indices, nspec,
-    Nk, Nd, total_nkz, elems_count,
-    remove_last_nz_bins, nboot_per_it):
+
+def my_cho_solve(fisher, y):
+    """ Since fisher matrix is positive definite and symmetric,
+    this function is faster than simple np.linalg.solve
+    (tested on jupyter notebook)
+    """
+    res = np.empty_like(y)
+    for jj in range(fisher.shape[0]):
+        c, low = cho_factor(fisher[jj])
+        res[jj] = cho_solve((c, low), y[jj])
+    return res
+
+
+def getOneSliceBoot(
+        spectra, booted_indices, nspec,
+        Nk, Nd, total_nkz, elems_count,
+        remove_last_nz_bins, nboot_per_it
+):
     boot_counts = getCounts(booted_indices)
     logging.info("    > Generated boot indices.")
 
@@ -99,23 +120,54 @@ def getOneSliceBoot(spectra, booted_indices, nspec,
     total_data = boot_counts @ spectra
 
     logging.info("    > Calculating bootstrapped inverse Fisher and power...")
-    total_power_b4, F = getPSandFisher(total_data, Nk, Nd, total_nkz, remove_last_nz_bins)
-    total_power = 0.5 * np.linalg.solve(F, total_power_b4)
+    total_power_b4, F = getPSandFisher(
+        total_data, Nk, Nd, total_nkz, remove_last_nz_bins)
+    total_power = 0.5 * my_cho_solve(F, total_power_b4)
 
     return total_power
 
-if __name__ == '__main__':
+
+def calculate_original(
+        args, nspec, spectra, Nk, Nd, total_nkz, outdir
+):
+    # Calculate original
+    if not args.calculate_originals:
+        return
+
+    logging.info("Calculating original power.")
+
+    total_data = np.ones((1, nspec)) @ spectra
+    total_power_b4, F = getPSandFisher(
+        total_data, Nk, Nd, total_nkz, args.remove_last_nz_bins)
+    orig_power = 0.5 * np.linalg.solve(F, total_power_b4)
+
+    # Save power to a file
+    # Set up output file
+    output_fname = ospath_join(
+        outdir, f"{args.fbase}bootstrap-original-power.txt")
+    np.savetxt(output_fname, orig_power)
+    logging.info(f"Original power saved as {output_fname}.")
+
+    output_fname = ospath_join(
+        outdir, f"{args.fbase}bootstrap-original-fisher.txt")
+    np.savetxt(output_fname, F[0])
+    logging.info(f"Original fisher saved as {output_fname}.")
+
+
+def main():
     # Arguments passed to run the script
-    parser = argparse.ArgumentParser(formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+    parser = argparse.ArgumentParser(
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
     parser.add_argument("Bootfile", help="File as described in QMLE.")
-    parser.add_argument("--bootnum", default=10000, type=int,
+    parser.add_argument(
+        "--bootnum", default=10000, type=int,
         help="Number of bootstrap resamples.")
     parser.add_argument("--nboot-per-it", default=10000, type=int,
-        help="Number of bootstraps to generate per iteration.")
-    parser.add_argument("--remove-last-nz-bins", default=0, type=int,
+                        help="Number of bootstraps to generate per iteration.")
+    parser.add_argument(
+        "--remove-last-nz-bins", default=0, type=int,
         help="Remove last nz bins to obtain invertable Fisher.")
     parser.add_argument("--seed", help="Seed", default=3422, type=int)
-    # parser.add_argument("--save-cov", action="store_true")
     parser.add_argument("--save-powers", action="store_true")
     parser.add_argument("--calculate-originals", action="store_true")
     parser.add_argument("--fbase", default="")
@@ -124,30 +176,22 @@ def getOneSliceBoot(spectra, booted_indices, nspec,
     outdir = ospath_dir(args.Bootfile)
     if outdir == "":
         outdir = "."
+
+    if args.fbase and args.fbase[-1] != '-':
+        args.fbase += '-'
+
     # Set up log
     logging.basicConfig(filename=f"{outdir}/bootstrapping.log",
-        level=logging.DEBUG)
+                        level=logging.DEBUG)
     logging.info(" ".join(sys.argv))
 
-    Nk, Nz, Nd, total_nkz, elems_count, nspec = getNumbersfromBootfile(args.Bootfile)
-    logging.info("There are %d subsamples.", nspec)
-    logging.info("Reading bootstrap dat file.")
+    Nk, Nz, Nd, total_nkz, elems_count, nspec = getNumbersfromBootfile(
+        args.Bootfile)
+    logging.info("There are %d subsamples. Reading bootstrap.dat file.", nspec)
     spectra = readBootFile(args.Bootfile, elems_count)
 
-    # Calculate original
-    if args.calculate_originals:
-        logging.info("Calculating original power.")
-        total_data = np.ones((1, nspec)) @ spectra
-        total_power_b4, F = getPSandFisher(total_data, Nk, Nd, total_nkz, args.remove_last_nz_bins)
-        orig_power = 0.5 * np.linalg.solve(F, total_power_b4)
-        # Save power to a file
-        # Set up output file
-        output_fname = ospath_join(outdir, f"{args.fbase}bootstrap-original-power.txt")
-        np.savetxt(output_fname, orig_power)
-        logging.info(f"Original power saved as {output_fname}.")
-        output_fname = ospath_join(outdir, f"{args.fbase}bootstrap-original-fisher.txt")
-        np.savetxt(output_fname, F[0])
-        logging.info(f"Original fisher saved as {output_fname}.")
+    calculate_original(
+        args, nspec, spectra, Nk, Nd, total_nkz, outdir)
 
     if args.bootnum <= 0:
         logging.info(f"No bootstraps were asked.")
@@ -155,30 +199,34 @@ def getOneSliceBoot(spectra, booted_indices, nspec,
 
     # Generate bootstrap realizations through indexes
     RND = np.random.default_rng(args.seed)
-    newpowersize = total_nkz-args.remove_last_nz_bins*Nk
+    newpowersize = total_nkz - args.remove_last_nz_bins * Nk
     total_power = np.empty((args.bootnum, newpowersize))
-    n_iter = int(args.bootnum/args.nboot_per_it)
+    n_iter = int(args.bootnum / args.nboot_per_it)
 
     for jj in range(n_iter):
         logging.info(f"Iteration {jj+1}/{n_iter}.")
-        i1 = jj*args.nboot_per_it
-        i2 = i1+args.nboot_per_it
-        booted_indices = RND.integers(low=0, high=nspec, size=(args.nboot_per_it, nspec))
-        total_power[i1:i2] = getOneSliceBoot(spectra, booted_indices, nspec,
+        i1 = jj * args.nboot_per_it
+        i2 = i1 + args.nboot_per_it
+        booted_indices = RND.integers(
+            low=0, high=nspec, size=(args.nboot_per_it, nspec))
+        total_power[i1:i2] = getOneSliceBoot(
+            spectra, booted_indices, nspec,
             Nk, Nd, total_nkz, elems_count,
             args.remove_last_nz_bins, args.nboot_per_it)
 
     bootstrap_cov = np.cov(total_power, rowvar=False)
-    output_fname = ospath_join(outdir, 
-        f"{args.fbase}bootstrap-cov-n{args.bootnum}-s{args.seed}.txt")
+    output_fname = ospath_join(
+        outdir, f"{args.fbase}bootstrap-cov-n{args.bootnum}-s{args.seed}.txt")
     np.savetxt(output_fname, bootstrap_cov)
     logging.info(f"Covariance saved as {output_fname}.")
 
     if args.save_powers:
-        output_fname = ospath_join(outdir, 
+        output_fname = ospath_join(
+            outdir,
             f"{args.fbase}bootstrap-power-n{args.bootnum}-s{args.seed}.txt")
         np.savetxt(output_fname, total_power)
         logging.info(f"Power saved as {output_fname}.")
 
-    
 
+if __name__ == '__main__':
+    main()
diff --git a/bin/regularizeBootstrapCov.py b/bin/regularizeBootstrapCov.py
index a1fcc65..905aad2 100644
--- a/bin/regularizeBootstrapCov.py
+++ b/bin/regularizeBootstrapCov.py
@@ -2,11 +2,13 @@
 import numpy as np
 from os.path import dirname as ospath_dir
 
+
 def normalize(matrix):
     fk_v = matrix.diagonal()
     norm = np.sqrt(np.outer(fk_v, fk_v))
     norm[norm == 0] = 1
-    return matrix/norm
+    return matrix / norm
+
 
 def safe_inverse(matrix):
     invmatrix = matrix.copy()
@@ -19,13 +21,16 @@ def safe_inverse(matrix):
 
 # evecs.T @ cov_boot @ evecs
 # Pat actually uses SVD, but that doesn't ensure positive definiteness
-# He also uses bootstrap evecs 
-# Here, I tried to do the same with eigenvalues. This way positive definiteness is satisfied.
+# He also uses bootstrap evecs
+# Here, I tried to do the same with eigenvalues.
+# This way positive definiteness is satisfied.
 # My findings: Bootstrap evecs works, chi2 slightly above mean dof
 #              QMLE evecs also works, chi2 slightly below mean dof
+
+
 def mcdonald_eval_fix(boot_cov, qmle_cov, use_boot_base_evecs=True):
-    #1) Use bootstrap evecs
     if use_boot_base_evecs:
+        # 1) Use bootstrap evecs
         evals_boot, evecs_boot = np.linalg.eigh(boot_cov)
 
         s_cov_qmle_bootevecs = np.diag(evecs_boot.T @ qmle_cov @ evecs_boot)
@@ -34,7 +39,7 @@ def mcdonald_eval_fix(boot_cov, qmle_cov, use_boot_base_evecs=True):
         evals_boot[small_vals] = s_cov_qmle_bootevecs[small_vals]
         newcov = evecs_boot @ np.diag(evals_boot) @ evecs_boot.T
     else:
-    #2) Use QMLE evecs
+        # 2) Use QMLE evecs
         evals_qmle, evecs_qmle = np.linalg.eigh(qmle_cov)
 
         s_cov_boot_qmleevecs = np.diag(evecs_qmle.T @ boot_cov @ evecs_qmle)
@@ -45,16 +50,21 @@ def mcdonald_eval_fix(boot_cov, qmle_cov, use_boot_base_evecs=True):
 
     return newcov
 
+
 if __name__ == '__main__':
     # Arguments passed to run the script
-    parser = argparse.ArgumentParser(formatter_class=argparse.ArgumentDefaultsHelpFormatter)
-    parser.add_argument("--boot-cov", help="Covariance from bootstrap file.", required=True)
-    parser.add_argument("--qmle-fisher",help="Fisher matrix from QMLE.", required=True)
-    parser.add_argument("--qmle-sparcity-cut", default=0.001, type=float, \
+    parser = argparse.ArgumentParser(
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+    parser.add_argument(
+        "--boot-cov", help="Covariance from bootstrap file.", required=True)
+    parser.add_argument(
+        "--qmle-fisher", help="Fisher matrix from QMLE.", required=True)
+    parser.add_argument(
+        "--qmle-sparcity-cut", default=0.001, type=float,
         help="Sparsity pattern to cut using QMLE Fisher matrix.")
     parser.add_argument("--use-qmle-evecs", action="store_true")
-    parser.add_argument("--iterations", type=int, default=1,
-        help="Number of iterations")
+    parser.add_argument("--iterations", type=int, default=500,
+                        help="Number of iterations")
     parser.add_argument("--reg-in-cov", action="store_true")
     parser.add_argument("--fbase", default="")
     args = parser.parse_args()
@@ -67,9 +77,12 @@ def mcdonald_eval_fix(boot_cov, qmle_cov, use_boot_base_evecs=True):
     normalized_qmle_cov = normalize(qmle_covariance)
     normalized_qmle_fisher = normalize(qmle_fisher)
 
-    matrix_to_use_for_sparsity = normalized_qmle_cov if args.reg_in_cov else normalized_qmle_fisher
+    matrix_to_use_for_sparsity = (
+        normalized_qmle_cov if args.reg_in_cov else normalized_qmle_fisher)
+
     if args.qmle_sparcity_cut > 0:
-        qmle_sparcity = np.abs(matrix_to_use_for_sparsity) > args.qmle_sparcity_cut
+        qmle_sparcity = np.abs(
+            matrix_to_use_for_sparsity) > args.qmle_sparcity_cut
     else:
         qmle_sparcity = np.ones(qmle_fisher.shape, dtype=bool)
 
@@ -79,13 +92,14 @@ def mcdonald_eval_fix(boot_cov, qmle_cov, use_boot_base_evecs=True):
             newcov = bootstrap_covariance * qmle_sparcity
         else:
             boostrap_fisher, _ = safe_inverse(bootstrap_covariance)
-            newcov, _ = safe_inverse(boostrap_fisher*qmle_sparcity)
+            newcov, _ = safe_inverse(boostrap_fisher * qmle_sparcity)
 
-        newcov = mcdonald_eval_fix(newcov, qmle_covariance, not args.use_qmle_evecs)
-        diff = np.abs(newcov-bootstrap_covariance)
-        bootstrap_covariance=newcov
+        newcov = mcdonald_eval_fix(
+            newcov, qmle_covariance, not args.use_qmle_evecs)
+        diff = np.abs(newcov - bootstrap_covariance)
+        bootstrap_covariance = newcov
 
-        if np.all(diff<1e-8):
+        if np.all(diff < 1e-8):
             print("Converged.")
             break
 
@@ -93,12 +107,5 @@ def mcdonald_eval_fix(boot_cov, qmle_cov, use_boot_base_evecs=True):
         bootstrap_covariance[idx, idx] = 0
 
     basis_txt = "qmle" if args.use_qmle_evecs else "boot"
-    np.savetxt(f"{outdir}/{args.fbase}regularized-bootstrap-cov-{basis_txt}-evecs.txt", bootstrap_covariance)
-
-
-
-
-
-
-
-
+    finalfname = f"{args.fbase}regularized-bootstrap-cov-{basis_txt}-evecs.txt"
+    np.savetxt(f"{outdir}/{finalfname}", bootstrap_covariance)
diff --git a/setup.py b/setup.py
index 46cf2eb..91bdae0 100644
--- a/setup.py
+++ b/setup.py
@@ -8,7 +8,7 @@
 
 setup(
     name="qsotools",
-    version="2.5.2",
+    version="2.5.3",
     packages=find_namespace_packages(where='py'),
     package_dir={'': 'py/'},
     scripts=binscripts,