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Code error with variable storage from selected feature

I'm using QGIS 3.6 with the built in Python text editor. I have found a snippet of code that I'm trying to make work, and I've modified it to the best of my abilities to fit my specific needs. I have a point layer called "Regulators" and it contains a field called "Town". The idea of the code is that when I select a single feature on the "Regulators" layer, the code will look at the "Town" field, and select all other features that match that field's value. I select a feature, run this code:
layer = iface.activeLayer()
field_name = 'Town'
values = []
for feat in layer.selectedFeatures():
tmp_value = feat[field_name]
if tmp_value not in values:
values.append(str(tmp_value))
strings = []
for val in values:
if val != values[-1]:
string = field_name + ' = ' + val + ' or '
strings.append(string)
else:
last_string = field_name + ' = ' + val
strings.append(last_string)
query = ''.join(strings)
request = QgsFeatureRequest().setFlags(QgsFeatureRequest.NoGeometry)
request.setSubsetOfAttributes([]).setFilterExpression(query)
selection = layer.getFeatures(request)
layer.setSelectedFeatures([k.id() for k in selection])
and I get this error:
Traceback (most recent call last):
File "C:\PROGRA~1\QGIS3~1.6\apps\Python37\lib\code.py", line 90, in runcode
exec(code, self.locals)
File "<input>", line 1, in <module>
File "<string>", line 24, in <module>
AttributeError: 'QgsVectorLayer' object has no attribute 'setSelectedFeatures'
I'm very much new to python, and see nothing wrong with line 1 or 5. I have found some other codes that do what I'm attempting here, but they also return errors, so I'm wondering if there is some method or function that has changed since this code was posted. The integrated compiler with QGIS is also much different than I am used to.
EDIT: I've updated the code and the error message based on feedback I've received on the post so far. I assume that QgsVectorLayer is the generic term for a vector layer being referenced, in this case the "Regulators" layer. but I don't understand why it's trying to use the setSelectedFeatures method as an attribute.

list index out of range reading files

I am a beginner of python and would need some help. I have run into a problem when trying to manipulating some dat-files.
I have created 159 dat.files (refitted_to_digit0_0.dat, refitted_to_digit0_1.dat, ...refitted_to_digit0_158.dat) containing time series data of two columns (timestep, value) of 2999 rows. In my python program I have created a list of these files with filelist_refit_0=glob.glob('refitted_to_digit0_*')
plist_refit_0=[]
I now try to load the second column of each 159 files into the plist_refit_0 so that each place in the list contains an array of 2999 values (second columns) that I will use for further manipulations. I have created a for-loop for this and use the len(filelist_refit_0) as the range for the loop. The length being 159 (number of files: 0-158).
However, when I run this I get an error message: list index out of range.
I have tried with a lower range for the for-loop and it seems to work up until range 66 but not above that. filelist_refit_0[66] refer to file refitted_to_digit0_158.dat and filelist_refit_0[67] refer to refitted_to_digit0_16.dat. filelist_refit_0[158] refer to refitted_to_digit0_99.dat. Instead of being sorted in ascending order based on the value 0->158 I think the plist_refit_0 have the files in ascending order based on the digits: refitted_to_digit0_0.dat first, then refitted_to_digit0_1.dat, then refitted_to_digit0_10.dat, then refitted_to_digit0_100.dat, then refitted_to_digit0_101.dat resulting in refitted_to_digit0_158.dat being on place 66 in the list. However, I still don't understand why the compiler interprets the index as being out of range above 66 when the length of the filelist_refit_0 being 159 and there really are 159 files, no matter the order. If anyone can explain this and have some advice how to solve this problem, I highly appreciate it! Thanks for your help.
I have tried the following to understand the sorting:
print len(filelist_refit_0) => 159
print filelist_refit_0[66] => refitted_to_digit0_158.dat
print filelist_refit_0[67] => refitted_to_digit0_16.dat
print filelist_refit_0[158] => refitted_to_digit0_99.dat
print filelist_refit_0[0] => refitted_to_digit0_0.dat
I have "manually" loaded the files and it seems to work for most index e.g.
t, p = loadtxt(filelist_refit_0[65], usecols=(0, 1), unpack=True)
plist_refit_0.append(p)
t, p = loadtxt(filelist_refit_0[67], usecols=(0, 1), unpack=True)
plist_refit_0.append(p)
print plist_refit_0[0]
print plist_refit_0[1]
BUT it does not work for index66!:
t, p = loadtxt(filelist_refit_0[66], usecols=(0, 1), unpack=True)
plist_refit_0.append(p)
Then I get error: list index out of range.
As can be seen above it refers to refitted_to_digit0_158.dat which is the last file. I have looked into the file and it looks exactly the same as all the other files, which the same number of columns and raw-elements (2999). Why is this entry different?
Python 2:
filelist_refit_0 = glob.glob('refitted_to_digit0_*')
plist_refit_0 = []
for i in range(len(filelist_refit_0)):
t, p = loadtxt(filelist_refit_0[i], usecols=(0, 1), unpack=True)
plist_refit_0.append(p)
Traceback (most recent call last):
File "test.py", line 107, in <module>
t,p=loadtxt(filelist_refit_0[i],usecols=(0,1),unpack=True)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/numpy/lib/npyio.py", line 1092, in loadtxt
for x in read_data(_loadtxt_chunksize):
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/numpy/lib/npyio.py", line 1012, in read_data
vals = [vals[j] for j in usecols]
IndexError: list index out of range

Python - Delete from Array while enumerating

Error:
Traceback (most recent call last):
File "<string>", line 10, in <module>
File "/Users/georg/Programmierung/Glyphs/Glyphs/Glyphs/Scripts/GlyphsApp.py", line 59, in __iter__
File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/PyObjC/objc/_convenience.py", line 589, in enumeratorGenerator
yield container_unwrap(anEnumerator.nextObject(), StopIteration)
objc.error: NSGenericException - *** Collection <__NSArrayM: 0x7f9906245480> was mutated while being enumerated.
I know this error occurs because I'm trying to delete objects from the array while also enumerating these objects. But I don't know how to solve it. I'm fairly new to object orientated programming and am limiting myself to scripting.
I searched the web and it seems to solve the error, I have to copy the array before deleting objects from it. When I'm tying to copy the array via deepcopy
import copy
pathcopy = copy.deepcopy(thisLayer.paths)
right before for path in thisLayer.paths:
But in this case I get the following error:
Cannot pickle Objective-C objects
Usually the program crashes after the first Glyph. For clarification: I work in Glyphsapp, a Typedesigning software.
Here is the Code:
# loops through every Glyph and deletes every path with nodes on the left half
for myGlyph in Glyphs.font.glyphs:
glname = myGlyph.name
thisLayer = Glyphs.font.glyphs[glname].layers[1]
middle = thisLayer.bounds.size.width/2+thisLayer.LSB
thisGlyph = thisLayer.parent
for path in thisLayer.paths: # this is where the code crashes
for thisNode in path.nodes:
if thisNode.position.x < middle:
#print thisNode.position.x
try:
thisLayer = path.parent()
except Exception as e:
thisLayer = path.parent
try:
thisLayer.removePath_ ( thisNode.parent() )
except AttributeError:
pass
Thank you in advance

Thank you very much Andreas,
with your help I was able to fix my code :-)
Here is the outcome:
for myGlyph in Glyphs.font.glyphs:
glname = myGlyph.name
thisLayer = Glyphs.font.glyphs[glname].layers[1]
middle = thisLayer.bounds.size.width/2+thisLayer.LSB
thisGlyph = thisLayer.parent
for path in thisLayer.paths:
for thisNode in path.nodes:
if thisNode.position.x < middle:
nodeList = []
nodeList.append(thisNode.parent())
nLCopy = nodeList[:]
for ncontainer in nLCopy:
thisLayer.removePath_ ( ncontainer )

Error: cannot perform reduce with flexible type

I'm trying to plot a histogram, but I'm keep getting this error;
Traceback (most recent call last):
File "<pyshell#62>", line 1, in <module>
plt.hist(a)
File "/usr/lib/pymodules/python2.7/matplotlib/pyplot.py", line 2827, in hist
stacked=stacked, **kwargs)
File "/usr/lib/pymodules/python2.7/matplotlib/axes.py", line 8312, in hist
xmin = min(xmin, xi.min())
File "/usr/lib/python2.7/dist-packages/numpy/core/_methods.py", line 21, in _amin
out=out, keepdims=keepdims)
TypeError: cannot perform reduce with flexible type
I'm very new to python and what I'm trying to do is this;
import numpy, matplotlib.pyplot
line = " "
a = []
b = []
c = []
alpha = []
beta = []
gama = []
while x.readline():
line = x.readline()
a.append(line[16:23])
b.append(line[25:32])
c.append(line[27:34])
alpha.append(line[40:47])
beta.append(line[49:54])
gama.append(line[56:63])
pyplot.hist(a)'
when ever I run this piece of code I'm getting that error. Where did I go wrong? I really appreciate a help

It looks like you are attempting to draw the histogram based on strings, rather than on numbers. Try something like this instead:
from matplotlib import pyplot
import random
# generate a series of numbers
a = [random.randint(1, 10) for _ in xrange(100)]
# generate a series of strings that look like numbers
b = [str(n) for n in a]
# try to create histograms of the data
pyplot.hist(a) # it produces a histogram (approximately flat, as expected)
pyplot.hist(b) # produces the error as you reported.
In general it is better to use a pre-written library to read data from external files (see e.g., numpy's genfromtxt or the csv module).
But at the very least, you likely need to treat the data you have read in as numerical, since readline returns strings. For instance:
for line in f.read():
fields = line.strip().split()
nums = [int(field) for field in fields]
now nums gives you a list of integers from that row.

python error using PaCal statistical package

I recently started exploring Python and have encountred a problem with a package named PaCal
Everything looks to be working fine except that I keep having this error anytime I want to print out some data (like in print A.mean() )
the error line is :
Traceback (most recent call last):
File "C:\Users\rmobenta\Desktop\tt.py", line 12, in <module>
print A.interval(0.95)
File "C:\Python27\lib\site-packages\pacal\distr.py", line 229, in interval
return self.quantile(p_lim), self.quantile(1.0 - p_lim)
File "C:\Python27\lib\site-packages\pacal\distr.py", line 215, in quantile
return self.get_piecewise_cdf().inverse(y)
File "C:\Python27\lib\site-packages\pacal\segments.py", line 1721, in inverse
x = findinv(segi.f, a = segi.a, b = segi.b, c = y, rtol = params.segments.cumint.reltol, maxiter = params.segments.cumint.maxiter) # TODO PInd, MInf
File "C:\Python27\lib\site-packages\pacal\utils.py", line 384, in findinv
return brentq(lambda x : fun(x) - c, a, b, **kwargs)
File "C:\Python27\lib\site-packages\scipy\optimize\zeros.py", line 414, in brentq
raise ValueError("rtol too small (%g < %g)" % (rtol, _rtol))
ValueError: rtol too small (1e-16 < 4.44089e-16)
I am using a two-line script that I got for a demo (given by the author of this package) and have no idea how to tackle this issue.
Here is the script:
from pacal import *
Y = UniformDistr(1, 2)
X = UniformDistr(3, 4)
A = atan(Y / X)
A.plot()
print A.mean()
print A.interval(0.95)

The problem comes from PaCal that defines in l.141 of params.py: segments.vumint.reltol = 1e-16.
This is the value passed as rtol in segments.py to the SciPy function brentq().
Finally it is compared to numpy.finfo(float).eps * 2 (l.413 and l.10 of scipy/optimize/zeros.py) and is unfortunately lesser.
So it could be a problem of PaCal implementation, not related to your code.
Note that the value you provided to interval() corresponds to the default value (l.222 of distr.py).
I think you should contact the PaCal developers to get more informations and probably open an issue.